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000
FXUS62 KCHS 201147
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
747 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVELY QUIET ALBEIT HOT DAY IS IN STORE AS THE UPPER RIDGE
BUILDS ACROSS THE EASTERN UNITED STATES AND LARGE SCALE SUBSIDENCE
DEVELOPS. MODEL TIME SECTIONS SHOW DEEP WNW TO NW FLOW...WITH
SPEEDS 5-15 KT BELOW 800 MB. THE SEA BREEZE WILL LIKELY BE PINNED
NEAR THE COASTLINE FOR MUCH OF THE AFTERNOON...EVENTUALLY PUSHING
SLOWLY INLAND LATE IN THE DAY. WE DID NOT MODIFY HIGH TEMPS VERY
MUCH FROM THE INHERITED NUMBERS. THICKNESS PROGS AND MOS NUMBERS
STILL SUPPORT MID TO UPPER 90S UNDER MOSTLY SUNNY SKIES. EVEN
LOCATIONS CLOSE TO THE BEACH WILL WARM INTO THE LOWER 90S DUE TO
THE DELAYED SEA BREEZE. MODEL SOUNDINGS SHOW A MODERATE CAP
DEVELOPING IN THE MID LEVELS...ALONG WITH SOME DRIER AIR MIXING
INTO THE BOUNDARY LAYER DURING THE HOURS OF PEAK HEATING. THIS
DOES NOT PRESENT A VERY FAVORABLE AIRMASS FOR CONVECTION...
ESPECIALLY WITH NO APPRECIABLE SHORTWAVE ENERGY AND A DELAYED SEA
BREEZE. WE ARE ONLY SHOWING SLIGHT CHANCE POPS DURING THE
AFTERNOON HOURS BUT WE THINK COVERAGE WILL BE QUITE LIMITED.
FORTUNATELY WITH DEWPOINTS MIXING DOWN INTO THE UPPER 60S TO LOWER
70S DURING THE WARMEST HOURS OF THE DAY...HEAT INDICES WILL REMAIN
IN CHECK WITH PEAK READINGS OF 105-107F.

TONIGHT SHOULD BE CLEAR AND QUIET WITH LOWS IN THE LOWER TO MIDDLE
70S AND LIGHT WINDS.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY THROUGH FRIDAY...A STRONG MID AND UPPER LEVEL RIDGE
CENTERED OVER THE DEEP SOUTH WILL EXPAND EASTWARD OVER THE REGION
ON THURSDAY...THEN ERODE A BIT ALONG ITS EASTERN PERIPHERY ON
FRIDAY AS AN UPPER LOW CROSSES NEW ENGLAND AND CAUSES A TROUGH TO
DIG SOUTHWARD JUST OFF THE MID-ATLANTIC COAST. MEANWHILE AT THE
SURFACE...HIGH PRESSURE WILL PREVAIL SOUTHEAST OF THE REGION WHILE
A TROUGH PERSISTS INLAND.

THIS PERIOD WILL BE CHARACTERIZED BY NORTHWEST FLOW ALOFT GIVEN THE
POSITION OF THE UPPER RIDGE...THEREFORE EXPECT HOT AND RELATIVELY
DRY CONDITIONS ACROSS THE FORECAST AREA. A PINNED SEA BREEZE...
DOWNSLOPE FLOW ALOFT AND STRONG SUBSIDENCE WILL SUPPORT HIGHS AROUND
100 IN MOST PLACES INLAND FROM THE IMMEDIATE COAST BOTH DAYS. HEAT
INDICES WILL EASILY REACH 105-110 DEGREES...WITH THE LOWEST VALUES
WELL INLAND WHERE DEWPOINTS WILL MIX OUT BEST. IT IS VERY POSSIBLE
THAT HEAT ADVISORIES COULD BE REQUIRED FOR AT LEAST PORTIONS OF THE
FORECAST AREA. LOWS WILL BE IN THE MID AND UPPER 70S BOTH THURSDAY
AND FRIDAY NIGHT. EXPECT ONLY ISOLATED CONVECTION TO DEVELOP ALONG
THE IMMEDIATE COAST AND PERHAPS INTO PARTS OF THE CHARLESTON
TRI-COUNTY AREA THURSDAY IN VICINITY OF THE PINNED SEA BREEZE...BUT
IT SHOULD BE TOO DRY AND SUBSIDENCE TOO STRONG FOR ANY CONVECTION
ELSEWHERE. THEN ON FRIDAY WITH SOME WEAKENING OF THE UPPER RIDGE
WILL FORECAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE AREA IN THE AFTERNOON/EVENING.

SATURDAY...A BACKDOOR COLD FRONT WILL BEGIN TO DROP SOUTHWARD ACROSS
THE AREA. THE FORECAST INDICATES A CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE CHARLESTON TRI-COUNTY AREA AND A SLIGHT
CHANCE ELSEWHERE ACCOMPANYING THE FRONTAL PASSAGE. TEMPERATURES WILL
COOL A BIT WITH INCREASED CLOUD COVER AND WEAKER SUBSIDENCE
ALOFT...WITH HIGHS IN THE MID TO UPPER 90S AWAY FROM THE IMMEDIATE
COAST.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH MOST OF
THE LONG TERM PERIOD WITH THE OVERALL SYNOPTIC PATTERN. A BACKDOOR
COLD FRONT WILL DROP SOUTH OF THE REGION LATE IN THE WEEKEND...
RESULTING IN A MOIST NORTHEAST FLOW WHICH WILL PREVAIL INTO AT LEAST
EARLY NEXT WEEK AS HIGH PRESSURE BUILDS FROM THE NORTH. THIS WILL
BRING UNSETTLED CONDITIONS TO THE AREA...WITH A SOLID CHANCE OF
SHOWERS AND THUNDERSTORMS EXPECTED ON SUNDAY WITH PROBABILITIES THEN
GRADUALLY LOWERING FROM NORTH TO SOUTH EACH DAY THROUGH WEDNESDAY.
MUCH COOLER TEMPERATURES WILL ALSO OCCUR ONCE THE FRONT MOVES
THROUGH...WITH TEMPERATURES MODERATING CLOSER TO SEASONAL NORMALS.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH 12Z THURSDAY.
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON
INTO EARLY THIS EVENING...BUT GIVEN LOW CONFIDENCE IN
COVERAGE/TIMING HAVE KEPT MENTION OUT OF THE FORECAST AT THIS
TIME.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT RESTRICTIONS
SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE REGION. LOW
CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS WELL AS
INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SOME NOCTURNAL SURGING WILL CONTINUE OVER THE NEARSHORE WATERS
THROUGH DAYBREAK WITH SPEEDS PUSHING 20 KT AT TIMES. LATER IN THE
MORNING ONCE THE GRADIENT RELAXES WE SHOULD HAVE S TO SW WINDS OF
10-15 KTS.

THURSDAY THROUGH MONDAY...A SOUTH/SOUTHWEST FLOW WILL PREVAIL
THROUGH FRIDAY OVER THE WATERS WITH SPEEDS AROUND 15 KT OR LESS AS
HIGH PRESSURE PREVAILS SOUTHEAST OF THE REGION WITH A TROUGH OF LOW
PRESSURE INLAND. A LOW LEVEL JET COULD STRENGTHEN FRIDAY NIGHT AHEAD
OF AN APPROACHING COLD FRONT AND COULD PUSH WINDS UPWARDS OF 15-20
KT OVER MAINLY THE OUTER GEORGIA WATERS. THE COLD FRONT WILL
GRADUALLY PUSH SOUTHWARD OVER THE WEEKEND...WITH WINDS VEERING
NORTHEAST BY SUNDAY. A STRONGER EAST/NORTHEAST FLOW WILL THEN
PREVAIL THROUGH MONDAY WITH WINDS REACHING UPWARDS OF 15-20 KT WITH
A FEW HIGHER GUSTS. SMALL CRAFT ADVISORY CONDITIONS COULD DEVELOP
OVER MAINLY THE OUTER GEORGIA WATERS AS SEAS BUILD UPWARDS OF 6 FT
WITH THE GOOD ONSHORE FETCH LATE MONDAY.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...JAQ
LONG TERM...JAQ
AVIATION...JAQ
MARINE...JRL/JAQ
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 201147
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
747 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVELY QUIET ALBEIT HOT DAY IS IN STORE AS THE UPPER RIDGE
BUILDS ACROSS THE EASTERN UNITED STATES AND LARGE SCALE SUBSIDENCE
DEVELOPS. MODEL TIME SECTIONS SHOW DEEP WNW TO NW FLOW...WITH
SPEEDS 5-15 KT BELOW 800 MB. THE SEA BREEZE WILL LIKELY BE PINNED
NEAR THE COASTLINE FOR MUCH OF THE AFTERNOON...EVENTUALLY PUSHING
SLOWLY INLAND LATE IN THE DAY. WE DID NOT MODIFY HIGH TEMPS VERY
MUCH FROM THE INHERITED NUMBERS. THICKNESS PROGS AND MOS NUMBERS
STILL SUPPORT MID TO UPPER 90S UNDER MOSTLY SUNNY SKIES. EVEN
LOCATIONS CLOSE TO THE BEACH WILL WARM INTO THE LOWER 90S DUE TO
THE DELAYED SEA BREEZE. MODEL SOUNDINGS SHOW A MODERATE CAP
DEVELOPING IN THE MID LEVELS...ALONG WITH SOME DRIER AIR MIXING
INTO THE BOUNDARY LAYER DURING THE HOURS OF PEAK HEATING. THIS
DOES NOT PRESENT A VERY FAVORABLE AIRMASS FOR CONVECTION...
ESPECIALLY WITH NO APPRECIABLE SHORTWAVE ENERGY AND A DELAYED SEA
BREEZE. WE ARE ONLY SHOWING SLIGHT CHANCE POPS DURING THE
AFTERNOON HOURS BUT WE THINK COVERAGE WILL BE QUITE LIMITED.
FORTUNATELY WITH DEWPOINTS MIXING DOWN INTO THE UPPER 60S TO LOWER
70S DURING THE WARMEST HOURS OF THE DAY...HEAT INDICES WILL REMAIN
IN CHECK WITH PEAK READINGS OF 105-107F.

TONIGHT SHOULD BE CLEAR AND QUIET WITH LOWS IN THE LOWER TO MIDDLE
70S AND LIGHT WINDS.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY THROUGH FRIDAY...A STRONG MID AND UPPER LEVEL RIDGE
CENTERED OVER THE DEEP SOUTH WILL EXPAND EASTWARD OVER THE REGION
ON THURSDAY...THEN ERODE A BIT ALONG ITS EASTERN PERIPHERY ON
FRIDAY AS AN UPPER LOW CROSSES NEW ENGLAND AND CAUSES A TROUGH TO
DIG SOUTHWARD JUST OFF THE MID-ATLANTIC COAST. MEANWHILE AT THE
SURFACE...HIGH PRESSURE WILL PREVAIL SOUTHEAST OF THE REGION WHILE
A TROUGH PERSISTS INLAND.

THIS PERIOD WILL BE CHARACTERIZED BY NORTHWEST FLOW ALOFT GIVEN THE
POSITION OF THE UPPER RIDGE...THEREFORE EXPECT HOT AND RELATIVELY
DRY CONDITIONS ACROSS THE FORECAST AREA. A PINNED SEA BREEZE...
DOWNSLOPE FLOW ALOFT AND STRONG SUBSIDENCE WILL SUPPORT HIGHS AROUND
100 IN MOST PLACES INLAND FROM THE IMMEDIATE COAST BOTH DAYS. HEAT
INDICES WILL EASILY REACH 105-110 DEGREES...WITH THE LOWEST VALUES
WELL INLAND WHERE DEWPOINTS WILL MIX OUT BEST. IT IS VERY POSSIBLE
THAT HEAT ADVISORIES COULD BE REQUIRED FOR AT LEAST PORTIONS OF THE
FORECAST AREA. LOWS WILL BE IN THE MID AND UPPER 70S BOTH THURSDAY
AND FRIDAY NIGHT. EXPECT ONLY ISOLATED CONVECTION TO DEVELOP ALONG
THE IMMEDIATE COAST AND PERHAPS INTO PARTS OF THE CHARLESTON
TRI-COUNTY AREA THURSDAY IN VICINITY OF THE PINNED SEA BREEZE...BUT
IT SHOULD BE TOO DRY AND SUBSIDENCE TOO STRONG FOR ANY CONVECTION
ELSEWHERE. THEN ON FRIDAY WITH SOME WEAKENING OF THE UPPER RIDGE
WILL FORECAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE AREA IN THE AFTERNOON/EVENING.

SATURDAY...A BACKDOOR COLD FRONT WILL BEGIN TO DROP SOUTHWARD ACROSS
THE AREA. THE FORECAST INDICATES A CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE CHARLESTON TRI-COUNTY AREA AND A SLIGHT
CHANCE ELSEWHERE ACCOMPANYING THE FRONTAL PASSAGE. TEMPERATURES WILL
COOL A BIT WITH INCREASED CLOUD COVER AND WEAKER SUBSIDENCE
ALOFT...WITH HIGHS IN THE MID TO UPPER 90S AWAY FROM THE IMMEDIATE
COAST.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH MOST OF
THE LONG TERM PERIOD WITH THE OVERALL SYNOPTIC PATTERN. A BACKDOOR
COLD FRONT WILL DROP SOUTH OF THE REGION LATE IN THE WEEKEND...
RESULTING IN A MOIST NORTHEAST FLOW WHICH WILL PREVAIL INTO AT LEAST
EARLY NEXT WEEK AS HIGH PRESSURE BUILDS FROM THE NORTH. THIS WILL
BRING UNSETTLED CONDITIONS TO THE AREA...WITH A SOLID CHANCE OF
SHOWERS AND THUNDERSTORMS EXPECTED ON SUNDAY WITH PROBABILITIES THEN
GRADUALLY LOWERING FROM NORTH TO SOUTH EACH DAY THROUGH WEDNESDAY.
MUCH COOLER TEMPERATURES WILL ALSO OCCUR ONCE THE FRONT MOVES
THROUGH...WITH TEMPERATURES MODERATING CLOSER TO SEASONAL NORMALS.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH 12Z THURSDAY.
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON
INTO EARLY THIS EVENING...BUT GIVEN LOW CONFIDENCE IN
COVERAGE/TIMING HAVE KEPT MENTION OUT OF THE FORECAST AT THIS
TIME.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT RESTRICTIONS
SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE REGION. LOW
CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS WELL AS
INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SOME NOCTURNAL SURGING WILL CONTINUE OVER THE NEARSHORE WATERS
THROUGH DAYBREAK WITH SPEEDS PUSHING 20 KT AT TIMES. LATER IN THE
MORNING ONCE THE GRADIENT RELAXES WE SHOULD HAVE S TO SW WINDS OF
10-15 KTS.

THURSDAY THROUGH MONDAY...A SOUTH/SOUTHWEST FLOW WILL PREVAIL
THROUGH FRIDAY OVER THE WATERS WITH SPEEDS AROUND 15 KT OR LESS AS
HIGH PRESSURE PREVAILS SOUTHEAST OF THE REGION WITH A TROUGH OF LOW
PRESSURE INLAND. A LOW LEVEL JET COULD STRENGTHEN FRIDAY NIGHT AHEAD
OF AN APPROACHING COLD FRONT AND COULD PUSH WINDS UPWARDS OF 15-20
KT OVER MAINLY THE OUTER GEORGIA WATERS. THE COLD FRONT WILL
GRADUALLY PUSH SOUTHWARD OVER THE WEEKEND...WITH WINDS VEERING
NORTHEAST BY SUNDAY. A STRONGER EAST/NORTHEAST FLOW WILL THEN
PREVAIL THROUGH MONDAY WITH WINDS REACHING UPWARDS OF 15-20 KT WITH
A FEW HIGHER GUSTS. SMALL CRAFT ADVISORY CONDITIONS COULD DEVELOP
OVER MAINLY THE OUTER GEORGIA WATERS AS SEAS BUILD UPWARDS OF 6 FT
WITH THE GOOD ONSHORE FETCH LATE MONDAY.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...JAQ
LONG TERM...JAQ
AVIATION...JAQ
MARINE...JRL/JAQ
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 201147
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
747 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVELY QUIET ALBEIT HOT DAY IS IN STORE AS THE UPPER RIDGE
BUILDS ACROSS THE EASTERN UNITED STATES AND LARGE SCALE SUBSIDENCE
DEVELOPS. MODEL TIME SECTIONS SHOW DEEP WNW TO NW FLOW...WITH
SPEEDS 5-15 KT BELOW 800 MB. THE SEA BREEZE WILL LIKELY BE PINNED
NEAR THE COASTLINE FOR MUCH OF THE AFTERNOON...EVENTUALLY PUSHING
SLOWLY INLAND LATE IN THE DAY. WE DID NOT MODIFY HIGH TEMPS VERY
MUCH FROM THE INHERITED NUMBERS. THICKNESS PROGS AND MOS NUMBERS
STILL SUPPORT MID TO UPPER 90S UNDER MOSTLY SUNNY SKIES. EVEN
LOCATIONS CLOSE TO THE BEACH WILL WARM INTO THE LOWER 90S DUE TO
THE DELAYED SEA BREEZE. MODEL SOUNDINGS SHOW A MODERATE CAP
DEVELOPING IN THE MID LEVELS...ALONG WITH SOME DRIER AIR MIXING
INTO THE BOUNDARY LAYER DURING THE HOURS OF PEAK HEATING. THIS
DOES NOT PRESENT A VERY FAVORABLE AIRMASS FOR CONVECTION...
ESPECIALLY WITH NO APPRECIABLE SHORTWAVE ENERGY AND A DELAYED SEA
BREEZE. WE ARE ONLY SHOWING SLIGHT CHANCE POPS DURING THE
AFTERNOON HOURS BUT WE THINK COVERAGE WILL BE QUITE LIMITED.
FORTUNATELY WITH DEWPOINTS MIXING DOWN INTO THE UPPER 60S TO LOWER
70S DURING THE WARMEST HOURS OF THE DAY...HEAT INDICES WILL REMAIN
IN CHECK WITH PEAK READINGS OF 105-107F.

TONIGHT SHOULD BE CLEAR AND QUIET WITH LOWS IN THE LOWER TO MIDDLE
70S AND LIGHT WINDS.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY THROUGH FRIDAY...A STRONG MID AND UPPER LEVEL RIDGE
CENTERED OVER THE DEEP SOUTH WILL EXPAND EASTWARD OVER THE REGION
ON THURSDAY...THEN ERODE A BIT ALONG ITS EASTERN PERIPHERY ON
FRIDAY AS AN UPPER LOW CROSSES NEW ENGLAND AND CAUSES A TROUGH TO
DIG SOUTHWARD JUST OFF THE MID-ATLANTIC COAST. MEANWHILE AT THE
SURFACE...HIGH PRESSURE WILL PREVAIL SOUTHEAST OF THE REGION WHILE
A TROUGH PERSISTS INLAND.

THIS PERIOD WILL BE CHARACTERIZED BY NORTHWEST FLOW ALOFT GIVEN THE
POSITION OF THE UPPER RIDGE...THEREFORE EXPECT HOT AND RELATIVELY
DRY CONDITIONS ACROSS THE FORECAST AREA. A PINNED SEA BREEZE...
DOWNSLOPE FLOW ALOFT AND STRONG SUBSIDENCE WILL SUPPORT HIGHS AROUND
100 IN MOST PLACES INLAND FROM THE IMMEDIATE COAST BOTH DAYS. HEAT
INDICES WILL EASILY REACH 105-110 DEGREES...WITH THE LOWEST VALUES
WELL INLAND WHERE DEWPOINTS WILL MIX OUT BEST. IT IS VERY POSSIBLE
THAT HEAT ADVISORIES COULD BE REQUIRED FOR AT LEAST PORTIONS OF THE
FORECAST AREA. LOWS WILL BE IN THE MID AND UPPER 70S BOTH THURSDAY
AND FRIDAY NIGHT. EXPECT ONLY ISOLATED CONVECTION TO DEVELOP ALONG
THE IMMEDIATE COAST AND PERHAPS INTO PARTS OF THE CHARLESTON
TRI-COUNTY AREA THURSDAY IN VICINITY OF THE PINNED SEA BREEZE...BUT
IT SHOULD BE TOO DRY AND SUBSIDENCE TOO STRONG FOR ANY CONVECTION
ELSEWHERE. THEN ON FRIDAY WITH SOME WEAKENING OF THE UPPER RIDGE
WILL FORECAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE AREA IN THE AFTERNOON/EVENING.

SATURDAY...A BACKDOOR COLD FRONT WILL BEGIN TO DROP SOUTHWARD ACROSS
THE AREA. THE FORECAST INDICATES A CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE CHARLESTON TRI-COUNTY AREA AND A SLIGHT
CHANCE ELSEWHERE ACCOMPANYING THE FRONTAL PASSAGE. TEMPERATURES WILL
COOL A BIT WITH INCREASED CLOUD COVER AND WEAKER SUBSIDENCE
ALOFT...WITH HIGHS IN THE MID TO UPPER 90S AWAY FROM THE IMMEDIATE
COAST.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH MOST OF
THE LONG TERM PERIOD WITH THE OVERALL SYNOPTIC PATTERN. A BACKDOOR
COLD FRONT WILL DROP SOUTH OF THE REGION LATE IN THE WEEKEND...
RESULTING IN A MOIST NORTHEAST FLOW WHICH WILL PREVAIL INTO AT LEAST
EARLY NEXT WEEK AS HIGH PRESSURE BUILDS FROM THE NORTH. THIS WILL
BRING UNSETTLED CONDITIONS TO THE AREA...WITH A SOLID CHANCE OF
SHOWERS AND THUNDERSTORMS EXPECTED ON SUNDAY WITH PROBABILITIES THEN
GRADUALLY LOWERING FROM NORTH TO SOUTH EACH DAY THROUGH WEDNESDAY.
MUCH COOLER TEMPERATURES WILL ALSO OCCUR ONCE THE FRONT MOVES
THROUGH...WITH TEMPERATURES MODERATING CLOSER TO SEASONAL NORMALS.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH 12Z THURSDAY.
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON
INTO EARLY THIS EVENING...BUT GIVEN LOW CONFIDENCE IN
COVERAGE/TIMING HAVE KEPT MENTION OUT OF THE FORECAST AT THIS
TIME.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT RESTRICTIONS
SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE REGION. LOW
CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS WELL AS
INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SOME NOCTURNAL SURGING WILL CONTINUE OVER THE NEARSHORE WATERS
THROUGH DAYBREAK WITH SPEEDS PUSHING 20 KT AT TIMES. LATER IN THE
MORNING ONCE THE GRADIENT RELAXES WE SHOULD HAVE S TO SW WINDS OF
10-15 KTS.

THURSDAY THROUGH MONDAY...A SOUTH/SOUTHWEST FLOW WILL PREVAIL
THROUGH FRIDAY OVER THE WATERS WITH SPEEDS AROUND 15 KT OR LESS AS
HIGH PRESSURE PREVAILS SOUTHEAST OF THE REGION WITH A TROUGH OF LOW
PRESSURE INLAND. A LOW LEVEL JET COULD STRENGTHEN FRIDAY NIGHT AHEAD
OF AN APPROACHING COLD FRONT AND COULD PUSH WINDS UPWARDS OF 15-20
KT OVER MAINLY THE OUTER GEORGIA WATERS. THE COLD FRONT WILL
GRADUALLY PUSH SOUTHWARD OVER THE WEEKEND...WITH WINDS VEERING
NORTHEAST BY SUNDAY. A STRONGER EAST/NORTHEAST FLOW WILL THEN
PREVAIL THROUGH MONDAY WITH WINDS REACHING UPWARDS OF 15-20 KT WITH
A FEW HIGHER GUSTS. SMALL CRAFT ADVISORY CONDITIONS COULD DEVELOP
OVER MAINLY THE OUTER GEORGIA WATERS AS SEAS BUILD UPWARDS OF 6 FT
WITH THE GOOD ONSHORE FETCH LATE MONDAY.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...JAQ
LONG TERM...JAQ
AVIATION...JAQ
MARINE...JRL/JAQ
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 201147
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
747 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVELY QUIET ALBEIT HOT DAY IS IN STORE AS THE UPPER RIDGE
BUILDS ACROSS THE EASTERN UNITED STATES AND LARGE SCALE SUBSIDENCE
DEVELOPS. MODEL TIME SECTIONS SHOW DEEP WNW TO NW FLOW...WITH
SPEEDS 5-15 KT BELOW 800 MB. THE SEA BREEZE WILL LIKELY BE PINNED
NEAR THE COASTLINE FOR MUCH OF THE AFTERNOON...EVENTUALLY PUSHING
SLOWLY INLAND LATE IN THE DAY. WE DID NOT MODIFY HIGH TEMPS VERY
MUCH FROM THE INHERITED NUMBERS. THICKNESS PROGS AND MOS NUMBERS
STILL SUPPORT MID TO UPPER 90S UNDER MOSTLY SUNNY SKIES. EVEN
LOCATIONS CLOSE TO THE BEACH WILL WARM INTO THE LOWER 90S DUE TO
THE DELAYED SEA BREEZE. MODEL SOUNDINGS SHOW A MODERATE CAP
DEVELOPING IN THE MID LEVELS...ALONG WITH SOME DRIER AIR MIXING
INTO THE BOUNDARY LAYER DURING THE HOURS OF PEAK HEATING. THIS
DOES NOT PRESENT A VERY FAVORABLE AIRMASS FOR CONVECTION...
ESPECIALLY WITH NO APPRECIABLE SHORTWAVE ENERGY AND A DELAYED SEA
BREEZE. WE ARE ONLY SHOWING SLIGHT CHANCE POPS DURING THE
AFTERNOON HOURS BUT WE THINK COVERAGE WILL BE QUITE LIMITED.
FORTUNATELY WITH DEWPOINTS MIXING DOWN INTO THE UPPER 60S TO LOWER
70S DURING THE WARMEST HOURS OF THE DAY...HEAT INDICES WILL REMAIN
IN CHECK WITH PEAK READINGS OF 105-107F.

TONIGHT SHOULD BE CLEAR AND QUIET WITH LOWS IN THE LOWER TO MIDDLE
70S AND LIGHT WINDS.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY THROUGH FRIDAY...A STRONG MID AND UPPER LEVEL RIDGE
CENTERED OVER THE DEEP SOUTH WILL EXPAND EASTWARD OVER THE REGION
ON THURSDAY...THEN ERODE A BIT ALONG ITS EASTERN PERIPHERY ON
FRIDAY AS AN UPPER LOW CROSSES NEW ENGLAND AND CAUSES A TROUGH TO
DIG SOUTHWARD JUST OFF THE MID-ATLANTIC COAST. MEANWHILE AT THE
SURFACE...HIGH PRESSURE WILL PREVAIL SOUTHEAST OF THE REGION WHILE
A TROUGH PERSISTS INLAND.

THIS PERIOD WILL BE CHARACTERIZED BY NORTHWEST FLOW ALOFT GIVEN THE
POSITION OF THE UPPER RIDGE...THEREFORE EXPECT HOT AND RELATIVELY
DRY CONDITIONS ACROSS THE FORECAST AREA. A PINNED SEA BREEZE...
DOWNSLOPE FLOW ALOFT AND STRONG SUBSIDENCE WILL SUPPORT HIGHS AROUND
100 IN MOST PLACES INLAND FROM THE IMMEDIATE COAST BOTH DAYS. HEAT
INDICES WILL EASILY REACH 105-110 DEGREES...WITH THE LOWEST VALUES
WELL INLAND WHERE DEWPOINTS WILL MIX OUT BEST. IT IS VERY POSSIBLE
THAT HEAT ADVISORIES COULD BE REQUIRED FOR AT LEAST PORTIONS OF THE
FORECAST AREA. LOWS WILL BE IN THE MID AND UPPER 70S BOTH THURSDAY
AND FRIDAY NIGHT. EXPECT ONLY ISOLATED CONVECTION TO DEVELOP ALONG
THE IMMEDIATE COAST AND PERHAPS INTO PARTS OF THE CHARLESTON
TRI-COUNTY AREA THURSDAY IN VICINITY OF THE PINNED SEA BREEZE...BUT
IT SHOULD BE TOO DRY AND SUBSIDENCE TOO STRONG FOR ANY CONVECTION
ELSEWHERE. THEN ON FRIDAY WITH SOME WEAKENING OF THE UPPER RIDGE
WILL FORECAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE AREA IN THE AFTERNOON/EVENING.

SATURDAY...A BACKDOOR COLD FRONT WILL BEGIN TO DROP SOUTHWARD ACROSS
THE AREA. THE FORECAST INDICATES A CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE CHARLESTON TRI-COUNTY AREA AND A SLIGHT
CHANCE ELSEWHERE ACCOMPANYING THE FRONTAL PASSAGE. TEMPERATURES WILL
COOL A BIT WITH INCREASED CLOUD COVER AND WEAKER SUBSIDENCE
ALOFT...WITH HIGHS IN THE MID TO UPPER 90S AWAY FROM THE IMMEDIATE
COAST.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH MOST OF
THE LONG TERM PERIOD WITH THE OVERALL SYNOPTIC PATTERN. A BACKDOOR
COLD FRONT WILL DROP SOUTH OF THE REGION LATE IN THE WEEKEND...
RESULTING IN A MOIST NORTHEAST FLOW WHICH WILL PREVAIL INTO AT LEAST
EARLY NEXT WEEK AS HIGH PRESSURE BUILDS FROM THE NORTH. THIS WILL
BRING UNSETTLED CONDITIONS TO THE AREA...WITH A SOLID CHANCE OF
SHOWERS AND THUNDERSTORMS EXPECTED ON SUNDAY WITH PROBABILITIES THEN
GRADUALLY LOWERING FROM NORTH TO SOUTH EACH DAY THROUGH WEDNESDAY.
MUCH COOLER TEMPERATURES WILL ALSO OCCUR ONCE THE FRONT MOVES
THROUGH...WITH TEMPERATURES MODERATING CLOSER TO SEASONAL NORMALS.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH 12Z THURSDAY.
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON
INTO EARLY THIS EVENING...BUT GIVEN LOW CONFIDENCE IN
COVERAGE/TIMING HAVE KEPT MENTION OUT OF THE FORECAST AT THIS
TIME.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT RESTRICTIONS
SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE REGION. LOW
CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS WELL AS
INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SOME NOCTURNAL SURGING WILL CONTINUE OVER THE NEARSHORE WATERS
THROUGH DAYBREAK WITH SPEEDS PUSHING 20 KT AT TIMES. LATER IN THE
MORNING ONCE THE GRADIENT RELAXES WE SHOULD HAVE S TO SW WINDS OF
10-15 KTS.

THURSDAY THROUGH MONDAY...A SOUTH/SOUTHWEST FLOW WILL PREVAIL
THROUGH FRIDAY OVER THE WATERS WITH SPEEDS AROUND 15 KT OR LESS AS
HIGH PRESSURE PREVAILS SOUTHEAST OF THE REGION WITH A TROUGH OF LOW
PRESSURE INLAND. A LOW LEVEL JET COULD STRENGTHEN FRIDAY NIGHT AHEAD
OF AN APPROACHING COLD FRONT AND COULD PUSH WINDS UPWARDS OF 15-20
KT OVER MAINLY THE OUTER GEORGIA WATERS. THE COLD FRONT WILL
GRADUALLY PUSH SOUTHWARD OVER THE WEEKEND...WITH WINDS VEERING
NORTHEAST BY SUNDAY. A STRONGER EAST/NORTHEAST FLOW WILL THEN
PREVAIL THROUGH MONDAY WITH WINDS REACHING UPWARDS OF 15-20 KT WITH
A FEW HIGHER GUSTS. SMALL CRAFT ADVISORY CONDITIONS COULD DEVELOP
OVER MAINLY THE OUTER GEORGIA WATERS AS SEAS BUILD UPWARDS OF 6 FT
WITH THE GOOD ONSHORE FETCH LATE MONDAY.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...JAQ
LONG TERM...JAQ
AVIATION...JAQ
MARINE...JRL/JAQ
CLIMATE...
EQUIPMENT...





  [top]

000
FXUS62 KFFC 201135
AFDFFC

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
735 AM EDT WED AUG 20 2014

.SHORT TERM /TODAY THROUGH THURSDAY/...
/ISSUED AT 340 AM EDT WED AUG 20 2014/
LATEST SATELLITE IR IMAGERY SHOWS AN UPPER LOW SPINNING OVER THE
GREAT LAKES REGION WITH SHORT WAVE DISTURBANCE TRAVERSING THE OHIO
VALLEY AND SPARKING CONVECTION FROM KENTUCKY NORTHWARD. IN THE WAKE
OF THIS DISTURBANCE... SHORT TERM MODELS AGREE ON AN ACTIVE
NORTHWEST MID AND UPPER LEVEL FLOW BECOMING ESTABLISHED OVER THE
OHIO AND TN VALLEYS BY THIS AFTERNOON AS STRONG HIGH PRESSURE BUILDS
INTO THE LOWER MS VALLEY REGION. THE RIDGING INFLUENCE WILL HELP
PUSH TEMPERATURES WELL INTO THE LOWER TO MID 90S FOR MOST AREAS
TODAY... PRODUCING 2500+ J/KG OF SURFACE BASED CAPE DURING THE
AFTERNOON. THIS COUPLED WITH AN ACTIVE NORTHWEST FLOW ACROSS TN AND
NORTH GA SUGGEST THE POTENTIAL FOR STORMS TO DEVELOP ACROSS TN
DURING DAYTIME HEATING... AND THEN PROPAGATING SOUTHWARD INTO NORTH
AND POTENTIALLY CENTRAL GA ALONG OUTFLOWS. THE LOCAL ARW AND WRF
HIRES MODELS... ALONG WITH THE NAM12 ARE ALL SUGGESTING THIS
POTENTIAL LATER THIS AFTERNOON. ALTHOUGH NOT EXPECTING WIDESPREAD
COVERAGE DUE TO SOME UPPER RIDGE INFLUENCE TO THE SOUTH AND
SOUTHWEST... A CHANCE OF CONVECTION FOR ALL AREAS IS WARRANTED
DURING THE AFTERNOON AND EARLY EVENING HOURS. SOME MID LEVEL DRY AIR
IS NOTED ON LATEST SATELLITE WATER VAPOR LOOP TO THE NORTHWEST AND
SHOULD SPREAD IN OVER THE AREA THIS AFTERNOON. THIS WOULD SERVE TO
ENHANCE STORM DOWNBURST... SUGGESTING THE GREATER STORM THREAT TODAY
WILL BE STRONG TO POTENTIALLY DAMAGING WINDS WITH THE STRONGER
STORMS. SPC HAS PUSHED A FIVE PERCENT CHANCE OF DAMAGING WINDS INTO
FAR NORTH GA TODAY... BUT SUSPECT THIS POTENTIAL WILL EXTEND MUCH
FURTHER SOUTH. WILL WORD FOR A FEW STRONG TO POSSIBLY SEVERE STORMS
IN THE HAZARDOUS WEATHER OUTLOOK FOR TODAY.

NO STORM THREAT TONIGHT WITH LOSS OF DAYTIME HEATING AND CONTINUED
RIDGE INFLUENCE. EXPECT SOME PATCHY FOG AND WARMER LOW TEMPS... WITH
MOST AREA LOWS HOLDING IN THE 70S.

THE THUNDERSTORM THREAT IS EXPECTED TO DIMINISH TO JUST SLIGHT
CHANCE AT BEST ON THURSDAY AS THE UPPER RIDGE BUILDS INTO THE STATE
FROM THE WEST. THIS WILL PUSH DAYTIME HIGHS WILL INTO THE MID AND
UPPER 90S FOR MANY AREAS... AND COULD HELP PUSH SOME HEAT INDEX
VALUES ACROSS PARTS OF CENTRAL GA CLOSE TO THE CRITICAL 105 DEGREE
MARK THURSDAY AFTERNOON. WILL MONITOR THIS POTENTIAL CLOSELY WITH
LATER FORECAST.

39

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
/ISSUED AT 340 AM EDT WED AUG 20 2014/
MEDIUM RANGE MODELS CONTINUE TO SHOW THE FORECAST AREA DOMINATED BY
STRONG UPPER-LEVEL RIDGING THROUGH THE MAJORITY OF THE EXTENDED
FORECAST PERIOD. GFS AND ECMWF REMAIN IN GOOD AGREEMENT THROUGH THE
WEEKEND BUT DIVERGE SOMEWHAT GOING INTO EARLY NEXT WEEK WITH THE
ECMWF FLATTEN THE RIDGE OVER US WHILE THE GFS...ALTHOUGH SHOWING
SOME WEAKENING... KEEPS THE RIDGE OVER THE REGION THROUGH WEDNESDAY.
STILL...THESE DIFFERENCES DO NOT ALTER THE GENERAL TREND OF HOT AND
MOSTLY DRY THROUGH THE WEEKEND WITH MODERATING TEMPERATURES AND
INCREASING PRECIPITATION CHANCES EARLY NEXT WEEK...WHICH IS WHAT WE
HAVE BEEN CARRYING IN THE EXTENDED FORECAST FOR THE PAST SEVERAL
DAYS NOW. WITH THIS IN MIND I DO NOT PLAN ON DEVIATING TOO MUCH FROM
PREVIOUS TRENDS IN THE FORECAST GRIDS. THROUGH THE WEEKEND THE
GFS/ECMWF KEEP THE CENTER OF THE UPPER RIDGE WEST OF THE STATE WITH
THE BEST SUBSIDENCE REMAINING WEST OF US AS WELL. WITH THIS IN MIND
I WILL KEEP THE SLIGHT CHANCE POPS INTO THE WEEKEND WITH CHANCE POPS
AS WE HEAD INTO THE FIRST HALF OF THE NEW WEEK.

20

&&

.AVIATION...
12Z UPDATE...
LATEST AREA OBS SHOW LIFR CIGS FROM NEWNAN TO HAMPTON AND GRIFFIN
THIS MORNING. THE WESTERLY FLOW IS SPREADING THESE CIGS DUE EAST...
AND SATELLITE LOOP ALONG WITH AREA OBS SUGGEST THESE LOW CIGS SHOULD
STAY SOUTH OF ATL THIS MORNING. PLAN TO SHOW VFR CONDITIONS THROUGH
THE TAF PERIOD AS LATEST TRENDS AND MODEL GUIDANCE SUPPORT THIS. GFS
AND NAM MODELS SHOW AN ACTIVE NW FLOW ALOFT THIS AFTERNOON... WHICH
WOULD SUPPORT DIURNAL CONVECTION BETWEEN 18-24Z TODAY. WILL SHOW
TEMPO -TSRA 19-23Z IN ALL TAFS. LIGHT WEST WINDS THIS MORNING WILL
MIX DOWN MORE WNW BY 15Z AND INCREASE TO AROUND 8-10KTS. EXPECT
LIGHT WNW WINDS TONIGHT AND NO LOW CIG THREAT. EXPECT SCT MID LEVEL
CU AND ONLY AN ISOLATED CONVECTIVE THREAT ON THU AS HIGH PRESSURE
BUILDS IN FROM THE WEST.

//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON PATCHY IFR/MVFR CIGS NOT EFFECTING ATL THIS MORNING. HIGH
CONFIDENCE ON ALL OTHER ELEMENTS.

39

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          96  71  97  73 /  30  20  20  20
ATLANTA         92  75  94  76 /  30  20  20  20
BLAIRSVILLE     88  66  88  68 /  30  30  20  20
CARTERSVILLE    93  70  96  71 /  30  20  20  20
COLUMBUS        96  74  95  76 /  30  20  20  20
GAINESVILLE     93  73  94  74 /  30  20  20  20
MACON           96  72  97  74 /  30  20  20  20
ROME            94  71  96  71 /  30  20  20  20
PEACHTREE CITY  92  70  94  72 /  30  20  20  20
VIDALIA         96  74  98  76 /  30  20  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...39
LONG TERM....20
AVIATION...39








000
FXUS62 KFFC 201135
AFDFFC

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
735 AM EDT WED AUG 20 2014

.SHORT TERM /TODAY THROUGH THURSDAY/...
/ISSUED AT 340 AM EDT WED AUG 20 2014/
LATEST SATELLITE IR IMAGERY SHOWS AN UPPER LOW SPINNING OVER THE
GREAT LAKES REGION WITH SHORT WAVE DISTURBANCE TRAVERSING THE OHIO
VALLEY AND SPARKING CONVECTION FROM KENTUCKY NORTHWARD. IN THE WAKE
OF THIS DISTURBANCE... SHORT TERM MODELS AGREE ON AN ACTIVE
NORTHWEST MID AND UPPER LEVEL FLOW BECOMING ESTABLISHED OVER THE
OHIO AND TN VALLEYS BY THIS AFTERNOON AS STRONG HIGH PRESSURE BUILDS
INTO THE LOWER MS VALLEY REGION. THE RIDGING INFLUENCE WILL HELP
PUSH TEMPERATURES WELL INTO THE LOWER TO MID 90S FOR MOST AREAS
TODAY... PRODUCING 2500+ J/KG OF SURFACE BASED CAPE DURING THE
AFTERNOON. THIS COUPLED WITH AN ACTIVE NORTHWEST FLOW ACROSS TN AND
NORTH GA SUGGEST THE POTENTIAL FOR STORMS TO DEVELOP ACROSS TN
DURING DAYTIME HEATING... AND THEN PROPAGATING SOUTHWARD INTO NORTH
AND POTENTIALLY CENTRAL GA ALONG OUTFLOWS. THE LOCAL ARW AND WRF
HIRES MODELS... ALONG WITH THE NAM12 ARE ALL SUGGESTING THIS
POTENTIAL LATER THIS AFTERNOON. ALTHOUGH NOT EXPECTING WIDESPREAD
COVERAGE DUE TO SOME UPPER RIDGE INFLUENCE TO THE SOUTH AND
SOUTHWEST... A CHANCE OF CONVECTION FOR ALL AREAS IS WARRANTED
DURING THE AFTERNOON AND EARLY EVENING HOURS. SOME MID LEVEL DRY AIR
IS NOTED ON LATEST SATELLITE WATER VAPOR LOOP TO THE NORTHWEST AND
SHOULD SPREAD IN OVER THE AREA THIS AFTERNOON. THIS WOULD SERVE TO
ENHANCE STORM DOWNBURST... SUGGESTING THE GREATER STORM THREAT TODAY
WILL BE STRONG TO POTENTIALLY DAMAGING WINDS WITH THE STRONGER
STORMS. SPC HAS PUSHED A FIVE PERCENT CHANCE OF DAMAGING WINDS INTO
FAR NORTH GA TODAY... BUT SUSPECT THIS POTENTIAL WILL EXTEND MUCH
FURTHER SOUTH. WILL WORD FOR A FEW STRONG TO POSSIBLY SEVERE STORMS
IN THE HAZARDOUS WEATHER OUTLOOK FOR TODAY.

NO STORM THREAT TONIGHT WITH LOSS OF DAYTIME HEATING AND CONTINUED
RIDGE INFLUENCE. EXPECT SOME PATCHY FOG AND WARMER LOW TEMPS... WITH
MOST AREA LOWS HOLDING IN THE 70S.

THE THUNDERSTORM THREAT IS EXPECTED TO DIMINISH TO JUST SLIGHT
CHANCE AT BEST ON THURSDAY AS THE UPPER RIDGE BUILDS INTO THE STATE
FROM THE WEST. THIS WILL PUSH DAYTIME HIGHS WILL INTO THE MID AND
UPPER 90S FOR MANY AREAS... AND COULD HELP PUSH SOME HEAT INDEX
VALUES ACROSS PARTS OF CENTRAL GA CLOSE TO THE CRITICAL 105 DEGREE
MARK THURSDAY AFTERNOON. WILL MONITOR THIS POTENTIAL CLOSELY WITH
LATER FORECAST.

39

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
/ISSUED AT 340 AM EDT WED AUG 20 2014/
MEDIUM RANGE MODELS CONTINUE TO SHOW THE FORECAST AREA DOMINATED BY
STRONG UPPER-LEVEL RIDGING THROUGH THE MAJORITY OF THE EXTENDED
FORECAST PERIOD. GFS AND ECMWF REMAIN IN GOOD AGREEMENT THROUGH THE
WEEKEND BUT DIVERGE SOMEWHAT GOING INTO EARLY NEXT WEEK WITH THE
ECMWF FLATTEN THE RIDGE OVER US WHILE THE GFS...ALTHOUGH SHOWING
SOME WEAKENING... KEEPS THE RIDGE OVER THE REGION THROUGH WEDNESDAY.
STILL...THESE DIFFERENCES DO NOT ALTER THE GENERAL TREND OF HOT AND
MOSTLY DRY THROUGH THE WEEKEND WITH MODERATING TEMPERATURES AND
INCREASING PRECIPITATION CHANCES EARLY NEXT WEEK...WHICH IS WHAT WE
HAVE BEEN CARRYING IN THE EXTENDED FORECAST FOR THE PAST SEVERAL
DAYS NOW. WITH THIS IN MIND I DO NOT PLAN ON DEVIATING TOO MUCH FROM
PREVIOUS TRENDS IN THE FORECAST GRIDS. THROUGH THE WEEKEND THE
GFS/ECMWF KEEP THE CENTER OF THE UPPER RIDGE WEST OF THE STATE WITH
THE BEST SUBSIDENCE REMAINING WEST OF US AS WELL. WITH THIS IN MIND
I WILL KEEP THE SLIGHT CHANCE POPS INTO THE WEEKEND WITH CHANCE POPS
AS WE HEAD INTO THE FIRST HALF OF THE NEW WEEK.

20

&&

.AVIATION...
12Z UPDATE...
LATEST AREA OBS SHOW LIFR CIGS FROM NEWNAN TO HAMPTON AND GRIFFIN
THIS MORNING. THE WESTERLY FLOW IS SPREADING THESE CIGS DUE EAST...
AND SATELLITE LOOP ALONG WITH AREA OBS SUGGEST THESE LOW CIGS SHOULD
STAY SOUTH OF ATL THIS MORNING. PLAN TO SHOW VFR CONDITIONS THROUGH
THE TAF PERIOD AS LATEST TRENDS AND MODEL GUIDANCE SUPPORT THIS. GFS
AND NAM MODELS SHOW AN ACTIVE NW FLOW ALOFT THIS AFTERNOON... WHICH
WOULD SUPPORT DIURNAL CONVECTION BETWEEN 18-24Z TODAY. WILL SHOW
TEMPO -TSRA 19-23Z IN ALL TAFS. LIGHT WEST WINDS THIS MORNING WILL
MIX DOWN MORE WNW BY 15Z AND INCREASE TO AROUND 8-10KTS. EXPECT
LIGHT WNW WINDS TONIGHT AND NO LOW CIG THREAT. EXPECT SCT MID LEVEL
CU AND ONLY AN ISOLATED CONVECTIVE THREAT ON THU AS HIGH PRESSURE
BUILDS IN FROM THE WEST.

//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON PATCHY IFR/MVFR CIGS NOT EFFECTING ATL THIS MORNING. HIGH
CONFIDENCE ON ALL OTHER ELEMENTS.

39

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          96  71  97  73 /  30  20  20  20
ATLANTA         92  75  94  76 /  30  20  20  20
BLAIRSVILLE     88  66  88  68 /  30  30  20  20
CARTERSVILLE    93  70  96  71 /  30  20  20  20
COLUMBUS        96  74  95  76 /  30  20  20  20
GAINESVILLE     93  73  94  74 /  30  20  20  20
MACON           96  72  97  74 /  30  20  20  20
ROME            94  71  96  71 /  30  20  20  20
PEACHTREE CITY  92  70  94  72 /  30  20  20  20
VIDALIA         96  74  98  76 /  30  20  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...39
LONG TERM....20
AVIATION...39








  [top]

000
FXUS62 KCAE 201050
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
650 AM EDT WED AUG 20 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES THROUGH FRIDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE
WILL INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER RIDGE BUILDING TO THE WEST OF THE AREA TODAY. WARMING 850MB
TEMPERATURES AND LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN
TEMPERATURES A FEW DEGREES WARMER THAN YESTERDAY. ONLY SLIGHT
CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS DUE TO DRIER AIR AND
BUILDING RIDGE ALOFT. MODELS SOUNDINGS SUGGEST MODERATE
INSTABILITY GIVEN WARM SURFACE TEMPERATURES BUT A RELATIVELY HIGH
LFC/POSSIBLE CAP. STRONG LIFTING ALSO NOT EXPECTED.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
UPPER RIDGE CONTINUES CENTERED TO THE WEST OF THE AREA. MODELS
SUGGEST LOW LEVEL WARMING THROUGH THE PERIOD. TEMPERATURES LIKELY
NEAR 100 DEGREES. GUIDANCE INDICATES DEW POINTS MIXING DOWN INTO
THE MID TO UPPER 60S ACROSS THE NORTHERN AND WESTERN COUNTIES TO
NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS SHOULD KEEP HEAT
INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110F. ONLY SLIGHT
CHANCE OF SHOWERS/TSTMS EXPECTED DUE TO DRIER AIR AND BUILDING
RIDGE ALOFT.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS EXPECTED THROUGH THE PERIOD.

UPPER LEVEL CLOUDS CROSSING THE REGION ALONG WITH LIGHT WINDS HAVE
KEPT FOG FROM FORMING AT THE TAF SITES. CUMULUS WILL DEVELOP
DURING THE LATE MORNING AND AFTERNOON HOURS WITH ISOLATED
CONVECTION POSSIBLE THIS AFTERNOON. CHANCES OF CONVECTION REMAIN
TOO LOW TO INCLUDE MENTION IN TAFS ATTM. WINDS WILL BE WESTERLY
AT 7 KNOTS OR LESS THROUGH THE PERIOD.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 201050
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
650 AM EDT WED AUG 20 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES THROUGH FRIDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE
WILL INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER RIDGE BUILDING TO THE WEST OF THE AREA TODAY. WARMING 850MB
TEMPERATURES AND LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN
TEMPERATURES A FEW DEGREES WARMER THAN YESTERDAY. ONLY SLIGHT
CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS DUE TO DRIER AIR AND
BUILDING RIDGE ALOFT. MODELS SOUNDINGS SUGGEST MODERATE
INSTABILITY GIVEN WARM SURFACE TEMPERATURES BUT A RELATIVELY HIGH
LFC/POSSIBLE CAP. STRONG LIFTING ALSO NOT EXPECTED.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
UPPER RIDGE CONTINUES CENTERED TO THE WEST OF THE AREA. MODELS
SUGGEST LOW LEVEL WARMING THROUGH THE PERIOD. TEMPERATURES LIKELY
NEAR 100 DEGREES. GUIDANCE INDICATES DEW POINTS MIXING DOWN INTO
THE MID TO UPPER 60S ACROSS THE NORTHERN AND WESTERN COUNTIES TO
NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS SHOULD KEEP HEAT
INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110F. ONLY SLIGHT
CHANCE OF SHOWERS/TSTMS EXPECTED DUE TO DRIER AIR AND BUILDING
RIDGE ALOFT.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS EXPECTED THROUGH THE PERIOD.

UPPER LEVEL CLOUDS CROSSING THE REGION ALONG WITH LIGHT WINDS HAVE
KEPT FOG FROM FORMING AT THE TAF SITES. CUMULUS WILL DEVELOP
DURING THE LATE MORNING AND AFTERNOON HOURS WITH ISOLATED
CONVECTION POSSIBLE THIS AFTERNOON. CHANCES OF CONVECTION REMAIN
TOO LOW TO INCLUDE MENTION IN TAFS ATTM. WINDS WILL BE WESTERLY
AT 7 KNOTS OR LESS THROUGH THE PERIOD.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$








000
FXUS62 KCHS 200854
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
454 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVELY QUIET ALBEIT HOT DAY IS IN STORE AS THE UPPER RIDGE
BUILDS ACROSS THE EASTERN UNITED STATES AND LARGE SCALE SUBSIDENCE
DEVELOPS. MODEL TIME SECTIONS SHOW DEEP WNW TO NW FLOW...WITH
SPEEDS 5-15 KT BELOW 800 MB. THE SEA BREEZE WILL LIKELY BE PINNED
NEAR THE COASTLINE FOR MUCH OF THE AFTERNOON...EVENTUALLY PUSHING
SLOWLY INLAND LATE IN THE DAY. WE DID NOT MODIFY HIGH TEMPS VERY
MUCH FROM THE INHERITED NUMBERS. THICKNESS PROGS AND MOS NUMBERS
STILL SUPPORT MID TO UPPER 90S UNDER MOSTLY SUNNY SKIES. EVEN
LOCATIONS CLOSE TO THE BEACH WILL WARM INTO THE LOWER 90S DUE TO
THE DELAYED SEA BREEZE. MODEL SOUNDINGS SHOW A MODERATE CAP
DEVELOPING IN THE MID LEVELS...ALONG WITH SOME DRIER AIR MIXING
INTO THE BOUNDARY LAYER DURING THE HOURS OF PEAK HEATING. THIS
DOES NOT PRESENT A VERY FAVORABLE AIRMASS FOR CONVECTION...
ESPECIALLY WITH NO APPRECIABLE SHORTWAVE ENERGY AND A DELAYED SEA
BREEZE. WE ARE ONLY SHOWING SLIGHT CHANCE POPS DURING THE
AFTERNOON HOURS BUT WE THINK COVERAGE WILL BE QUITE LIMITED.
FORTUNATELY WITH DEWPOINTS MIXING DOWN INTO THE UPPER 60S TO LOWER
70S DURING THE WARMEST HOURS OF THE DAY...HEAT INDICES WILL REMAIN
IN CHECK WITH PEAK READINGS OF 105-107F.

TONIGHT SHOULD BE CLEAR AND QUIET WITH LOWS IN THE LOWER TO MIDDLE
70S AND LIGHT WINDS.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY THROUGH FRIDAY...A STRONG MID AND UPPER LEVEL RIDGE
CENTERED OVER THE DEEP SOUTH WILL EXPAND EASTWARD OVER THE REGION
ON THURSDAY...THEN ERODE A BIT ALONG ITS EASTERN PERIPHERY ON
FRIDAY AS AN UPPER LOW CROSSES NEW ENGLAND AND CAUSES A TROUGH TO
DIG SOUTHWARD JUST OFF THE MID-ATLANTIC COAST. MEANWHILE AT THE
SURFACE...HIGH PRESSURE WILL PREVAIL SOUTHEAST OF THE REGION WHILE
A TROUGH PERSISTS INLAND.

THIS PERIOD WILL BE CHARACTERIZED BY NORTHWEST FLOW ALOFT GIVEN THE
POSITION OF THE UPPER RIDGE...THEREFORE EXPECT HOT AND RELATIVELY
DRY CONDITIONS ACROSS THE FORECAST AREA. A PINNED SEA BREEZE...
DOWNSLOPE FLOW ALOFT AND STRONG SUBSIDENCE WILL SUPPORT HIGHS AROUND
100 IN MOST PLACES INLAND FROM THE IMMEDIATE COAST BOTH DAYS. HEAT
INDICES WILL EASILY REACH 105-110 DEGREES...WITH THE LOWEST VALUES
WELL INLAND WHERE DEWPOINTS WILL MIX OUT BEST. IT IS VERY POSSIBLE
THAT HEAT ADVISORIES COULD BE REQUIRED FOR AT LEAST PORTIONS OF THE
FORECAST AREA. LOWS WILL BE IN THE MID AND UPPER 70S BOTH THURSDAY
AND FRIDAY NIGHT. EXPECT ONLY ISOLATED CONVECTION TO DEVELOP ALONG
THE IMMEDIATE COAST AND PERHAPS INTO PARTS OF THE CHARLESTON
TRI-COUNTY AREA THURSDAY IN VICINITY OF THE PINNED SEA BREEZE...BUT
IT SHOULD BE TOO DRY AND SUBSIDENCE TOO STRONG FOR ANY CONVECTION
ELSEWHERE. THEN ON FRIDAY WITH SOME WEAKENING OF THE UPPER RIDGE
WILL FORECAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE AREA IN THE AFTERNOON/EVENING.

SATURDAY...A BACKDOOR COLD FRONT WILL BEGIN TO DROP SOUTHWARD ACROSS
THE AREA. THE FORECAST INDICATES A CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE CHARLESTON TRI-COUNTY AREA AND A SLIGHT
CHANCE ELSEWHERE ACCOMPANYING THE FRONTAL PASSAGE. TEMPERATURES WILL
COOL A BIT WITH INCREASED CLOUD COVER AND WEAKER SUBSIDENCE
ALOFT...WITH HIGHS IN THE MID TO UPPER 90S AWAY FROM THE IMMEDIATE
COAST.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH MOST OF
THE LONG TERM PERIOD WITH THE OVERALL SYNOPTIC PATTERN. A BACKDOOR
COLD FRONT WILL DROP SOUTH OF THE REGION LATE IN THE WEEKEND...
RESULTING IN A MOIST NORTHEAST FLOW WHICH WILL PREVAIL INTO AT LEAST
EARLY NEXT WEEK AS HIGH PRESSURE BUILDS FROM THE NORTH. THIS WILL
BRING UNSETTLED CONDITIONS TO THE AREA...WITH A SOLID CHANCE OF
SHOWERS AND THUNDERSTORMS EXPECTED ON SUNDAY WITH PROBABILITIES THEN
GRADUALLY LOWERING FROM NORTH TO SOUTH EACH DAY THROUGH WEDNESDAY.
MUCH COOLER TEMPERATURES WILL ALSO OCCUR ONCE THE FRONT MOVES
THROUGH...WITH TEMPERATURES MODERATING CLOSER TO SEASONAL NORMALS.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
RELATIVELY QUIET CONDITIONS EXPECTED THROUGH 06Z THU. ONLY AN
ISOLATED CHANCE FOR A SHOWER OR TSTM AT EITHER TERMINAL THIS
AFTERNOON BUT WE DID NOT INCLUDE ANY MENTION AT THIS TIME. VFR
OTHERWISE.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED THROUGH
FRIDAY. INCREASING CHANCES FOR FLIGHT RESTRICTIONS SATURDAY INTO
SUNDAY AS A FRONT DROPS THROUGH THE REGION. LOW CEILINGS AND/OR
VSBYS ARE POSSIBLE WITH THE FRONT...AS WELL AS INCREASING CHANCES
FOR SHOWERS AND TSTMS.

&&

.MARINE...
SOME NOCTURNAL SURGING WILL CONTINUE OVER THE NEARSHORE WATERS
THROUGH DAYBREAK WITH SPEEDS PUSHING 20 KT AT TIMES. LATER IN THE
MORNING ONCE THE GRADIENT RELAXES WE SHOULD HAVE S TO SW WINDS OF
10-15 KTS.

THURSDAY THROUGH MONDAY...A SOUTH/SOUTHWEST FLOW WILL PREVAIL
THROUGH FRIDAY OVER THE WATERS WITH SPEEDS AROUND 15 KT OR LESS AS
HIGH PRESSURE PREVAILS SOUTHEAST OF THE REGION WITH A TROUGH OF LOW
PRESSURE INLAND. A LOW LEVEL JET COULD STRENGTHEN FRIDAY NIGHT AHEAD
OF AN APPROACHING COLD FRONT AND COULD PUSH WINDS UPWARDS OF 15-20
KT OVER MAINLY THE OUTER GEORGIA WATERS. THE COLD FRONT WILL
GRADUALLY PUSH SOUTHWARD OVER THE WEEKEND...WITH WINDS VEERING
NORTHEAST BY SUNDAY. A STRONGER EAST/NORTHEAST FLOW WILL THEN
PREVAIL THROUGH MONDAY WITH WINDS REACHING UPWARDS OF 15-20 KT WITH
A FEW HIGHER GUSTS. SMALL CRAFT ADVISORY CONDITIONS COULD DEVELOP
OVER MAINLY THE OUTER GEORGIA WATERS AS SEAS BUILD UPWARDS OF 6 FT
WITH THE GOOD ONSHORE FETCH LATE MONDAY.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...JAQ
LONG TERM...JAQ
AVIATION...JAQ/JRL
MARINE...JAQ/JRL
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 200854
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
454 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A RELATIVELY QUIET ALBEIT HOT DAY IS IN STORE AS THE UPPER RIDGE
BUILDS ACROSS THE EASTERN UNITED STATES AND LARGE SCALE SUBSIDENCE
DEVELOPS. MODEL TIME SECTIONS SHOW DEEP WNW TO NW FLOW...WITH
SPEEDS 5-15 KT BELOW 800 MB. THE SEA BREEZE WILL LIKELY BE PINNED
NEAR THE COASTLINE FOR MUCH OF THE AFTERNOON...EVENTUALLY PUSHING
SLOWLY INLAND LATE IN THE DAY. WE DID NOT MODIFY HIGH TEMPS VERY
MUCH FROM THE INHERITED NUMBERS. THICKNESS PROGS AND MOS NUMBERS
STILL SUPPORT MID TO UPPER 90S UNDER MOSTLY SUNNY SKIES. EVEN
LOCATIONS CLOSE TO THE BEACH WILL WARM INTO THE LOWER 90S DUE TO
THE DELAYED SEA BREEZE. MODEL SOUNDINGS SHOW A MODERATE CAP
DEVELOPING IN THE MID LEVELS...ALONG WITH SOME DRIER AIR MIXING
INTO THE BOUNDARY LAYER DURING THE HOURS OF PEAK HEATING. THIS
DOES NOT PRESENT A VERY FAVORABLE AIRMASS FOR CONVECTION...
ESPECIALLY WITH NO APPRECIABLE SHORTWAVE ENERGY AND A DELAYED SEA
BREEZE. WE ARE ONLY SHOWING SLIGHT CHANCE POPS DURING THE
AFTERNOON HOURS BUT WE THINK COVERAGE WILL BE QUITE LIMITED.
FORTUNATELY WITH DEWPOINTS MIXING DOWN INTO THE UPPER 60S TO LOWER
70S DURING THE WARMEST HOURS OF THE DAY...HEAT INDICES WILL REMAIN
IN CHECK WITH PEAK READINGS OF 105-107F.

TONIGHT SHOULD BE CLEAR AND QUIET WITH LOWS IN THE LOWER TO MIDDLE
70S AND LIGHT WINDS.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY THROUGH FRIDAY...A STRONG MID AND UPPER LEVEL RIDGE
CENTERED OVER THE DEEP SOUTH WILL EXPAND EASTWARD OVER THE REGION
ON THURSDAY...THEN ERODE A BIT ALONG ITS EASTERN PERIPHERY ON
FRIDAY AS AN UPPER LOW CROSSES NEW ENGLAND AND CAUSES A TROUGH TO
DIG SOUTHWARD JUST OFF THE MID-ATLANTIC COAST. MEANWHILE AT THE
SURFACE...HIGH PRESSURE WILL PREVAIL SOUTHEAST OF THE REGION WHILE
A TROUGH PERSISTS INLAND.

THIS PERIOD WILL BE CHARACTERIZED BY NORTHWEST FLOW ALOFT GIVEN THE
POSITION OF THE UPPER RIDGE...THEREFORE EXPECT HOT AND RELATIVELY
DRY CONDITIONS ACROSS THE FORECAST AREA. A PINNED SEA BREEZE...
DOWNSLOPE FLOW ALOFT AND STRONG SUBSIDENCE WILL SUPPORT HIGHS AROUND
100 IN MOST PLACES INLAND FROM THE IMMEDIATE COAST BOTH DAYS. HEAT
INDICES WILL EASILY REACH 105-110 DEGREES...WITH THE LOWEST VALUES
WELL INLAND WHERE DEWPOINTS WILL MIX OUT BEST. IT IS VERY POSSIBLE
THAT HEAT ADVISORIES COULD BE REQUIRED FOR AT LEAST PORTIONS OF THE
FORECAST AREA. LOWS WILL BE IN THE MID AND UPPER 70S BOTH THURSDAY
AND FRIDAY NIGHT. EXPECT ONLY ISOLATED CONVECTION TO DEVELOP ALONG
THE IMMEDIATE COAST AND PERHAPS INTO PARTS OF THE CHARLESTON
TRI-COUNTY AREA THURSDAY IN VICINITY OF THE PINNED SEA BREEZE...BUT
IT SHOULD BE TOO DRY AND SUBSIDENCE TOO STRONG FOR ANY CONVECTION
ELSEWHERE. THEN ON FRIDAY WITH SOME WEAKENING OF THE UPPER RIDGE
WILL FORECAST A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE AREA IN THE AFTERNOON/EVENING.

SATURDAY...A BACKDOOR COLD FRONT WILL BEGIN TO DROP SOUTHWARD ACROSS
THE AREA. THE FORECAST INDICATES A CHANCE OF SHOWERS AND
THUNDERSTORMS ACROSS THE CHARLESTON TRI-COUNTY AREA AND A SLIGHT
CHANCE ELSEWHERE ACCOMPANYING THE FRONTAL PASSAGE. TEMPERATURES WILL
COOL A BIT WITH INCREASED CLOUD COVER AND WEAKER SUBSIDENCE
ALOFT...WITH HIGHS IN THE MID TO UPPER 90S AWAY FROM THE IMMEDIATE
COAST.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH MOST OF
THE LONG TERM PERIOD WITH THE OVERALL SYNOPTIC PATTERN. A BACKDOOR
COLD FRONT WILL DROP SOUTH OF THE REGION LATE IN THE WEEKEND...
RESULTING IN A MOIST NORTHEAST FLOW WHICH WILL PREVAIL INTO AT LEAST
EARLY NEXT WEEK AS HIGH PRESSURE BUILDS FROM THE NORTH. THIS WILL
BRING UNSETTLED CONDITIONS TO THE AREA...WITH A SOLID CHANCE OF
SHOWERS AND THUNDERSTORMS EXPECTED ON SUNDAY WITH PROBABILITIES THEN
GRADUALLY LOWERING FROM NORTH TO SOUTH EACH DAY THROUGH WEDNESDAY.
MUCH COOLER TEMPERATURES WILL ALSO OCCUR ONCE THE FRONT MOVES
THROUGH...WITH TEMPERATURES MODERATING CLOSER TO SEASONAL NORMALS.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
RELATIVELY QUIET CONDITIONS EXPECTED THROUGH 06Z THU. ONLY AN
ISOLATED CHANCE FOR A SHOWER OR TSTM AT EITHER TERMINAL THIS
AFTERNOON BUT WE DID NOT INCLUDE ANY MENTION AT THIS TIME. VFR
OTHERWISE.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED THROUGH
FRIDAY. INCREASING CHANCES FOR FLIGHT RESTRICTIONS SATURDAY INTO
SUNDAY AS A FRONT DROPS THROUGH THE REGION. LOW CEILINGS AND/OR
VSBYS ARE POSSIBLE WITH THE FRONT...AS WELL AS INCREASING CHANCES
FOR SHOWERS AND TSTMS.

&&

.MARINE...
SOME NOCTURNAL SURGING WILL CONTINUE OVER THE NEARSHORE WATERS
THROUGH DAYBREAK WITH SPEEDS PUSHING 20 KT AT TIMES. LATER IN THE
MORNING ONCE THE GRADIENT RELAXES WE SHOULD HAVE S TO SW WINDS OF
10-15 KTS.

THURSDAY THROUGH MONDAY...A SOUTH/SOUTHWEST FLOW WILL PREVAIL
THROUGH FRIDAY OVER THE WATERS WITH SPEEDS AROUND 15 KT OR LESS AS
HIGH PRESSURE PREVAILS SOUTHEAST OF THE REGION WITH A TROUGH OF LOW
PRESSURE INLAND. A LOW LEVEL JET COULD STRENGTHEN FRIDAY NIGHT AHEAD
OF AN APPROACHING COLD FRONT AND COULD PUSH WINDS UPWARDS OF 15-20
KT OVER MAINLY THE OUTER GEORGIA WATERS. THE COLD FRONT WILL
GRADUALLY PUSH SOUTHWARD OVER THE WEEKEND...WITH WINDS VEERING
NORTHEAST BY SUNDAY. A STRONGER EAST/NORTHEAST FLOW WILL THEN
PREVAIL THROUGH MONDAY WITH WINDS REACHING UPWARDS OF 15-20 KT WITH
A FEW HIGHER GUSTS. SMALL CRAFT ADVISORY CONDITIONS COULD DEVELOP
OVER MAINLY THE OUTER GEORGIA WATERS AS SEAS BUILD UPWARDS OF 6 FT
WITH THE GOOD ONSHORE FETCH LATE MONDAY.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...JAQ
LONG TERM...JAQ
AVIATION...JAQ/JRL
MARINE...JAQ/JRL
CLIMATE...
EQUIPMENT...







000
FXUS62 KFFC 200740
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
340 AM EDT WED AUG 20 2014

.SHORT TERM /TODAY THROUGH THURSDAY/...
LATEST SATELLITE IR IMAGERY SHOWS AN UPPER LOW SPINNING OVER THE
GREAT LAKES REGION WITH SHORT WAVE DISTURBANCE TRAVERSING THE OHIO
VALLEY AND SPARKING CONVECTION FROM KENTUCKY NORTHWARD. IN THE WAKE
OF THIS DISTURBANCE... SHORT TERM MODELS AGREE ON AN ACTIVE
NORTHWEST MID AND UPPER LEVEL FLOW BECOMING ESTABLISHED OVER THE
OHIO AND TN VALLEYS BY THIS AFTERNOON AS STRONG HIGH PRESSURE BUILDS
INTO THE LOWER MS VALLEY REGION. THE RIDGING INFLUENCE WILL HELP
PUSH TEMPERATURES WELL INTO THE LOWER TO MID 90S FOR MOST AREAS
TODAY... PRODUCING 2500+ J/KG OF SURFACE BASED CAPE DURING THE
AFTERNOON. THIS COUPLED WITH AN ACTIVE NORTHWEST FLOW ACROSS TN AND
NORTH GA SUGGEST THE POTENTIAL FOR STORMS TO DEVELOP ACROSS TN
DURING DAYTIME HEATING... AND THEN PROPAGATING SOUTHWARD INTO NORTH
AND POTENTIALLY CENTRAL GA ALONG OUTFLOWS. THE LOCAL ARW AND WRF
HIRES MODELS... ALONG WITH THE NAM12 ARE ALL SUGGESTING THIS
POTENTIAL LATER THIS AFTERNOON. ALTHOUGH NOT EXPECTING WIDESPREAD
COVERAGE DUE TO SOME UPPER RIDGE INFLUENCE TO THE SOUTH AND
SOUTHWEST... A CHANCE OF CONVECTION FOR ALL AREAS IS WARRANTED
DURING THE AFTERNOON AND EARLY EVENING HOURS. SOME MID LEVEL DRY AIR
IS NOTED ON LATEST SATELLITE WATER VAPOR LOOP TO THE NORTHWEST AND
SHOULD SPREAD IN OVER THE AREA THIS AFTERNOON. THIS WOULD SERVE TO
ENHANCE STORM DOWNBURST... SUGGESTING THE GREATER STORM THREAT TODAY
WILL BE STRONG TO POTENTIALLY DAMAGING WINDS WITH THE STRONGER
STORMS. SPC HAS PUSHED A FIVE PERCENT CHANCE OF DAMAGING WINDS INTO
FAR NORTH GA TODAY... BUT SUSPECT THIS POTENTIAL WILL EXTEND MUCH
FURTHER SOUTH. WILL WORD FOR A FEW STRONG TO POSSIBLY SEVERE STORMS
IN THE HAZARDOUS WEATHER OUTLOOK FOR TODAY.

NO STORM THREAT TONIGHT WITH LOSS OF DAYTIME HEATING AND CONTINUED
RIDGE INFLUENCE. EXPECT SOME PATCHY FOG AND WARMER LOW TEMPS... WITH
MOST AREA LOWS HOLDING IN THE 70S.

THE THUNDERSTORM THREAT IS EXPECTED TO DIMINISH TO JUST SLIGHT
CHANCE AT BEST ON THURSDAY AS THE UPPER RIDGE BUILDS INTO THE STATE
FROM THE WEST. THIS WILL PUSH DAYTIME HIGHS WILL INTO THE MID AND
UPPER 90S FOR MANY AREAS... AND COULD HELP PUSH SOME HEAT INDEX
VALUES ACROSS PARTS OF CENTRAL GA CLOSE TO THE CRITICAL 105 DEGREE
MARK THURSDAY AFTERNOON. WILL MONITOR THIS POTENTIAL CLOSELY WITH
LATER FORECAST.

39

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE MODELS CONTINUE TO SHOW THE FORECAST AREA DOMINATED BY
STRONG UPPER-LEVEL RIDGING THROUGH THE MAJORITY OF THE EXTENDED
FORECAST PERIOD. GFS AND ECMWF REMAIN IN GOOD AGREEMENT THROUGH THE
WEEKEND BUT DIVERGE SOMEWHAT GOING INTO EARLY NEXT WEEK WITH THE
ECMWF FLATTEN THE RIDGE OVER US WHILE THE GFS...ALTHOUGH SHOWING
SOME WEAKENING... KEEPS THE RIDGE OVER THE REGION THROUGH WEDNESDAY.
STILL...THESE DIFFERENCES DO NOT ALTER THE GENERAL TREND OF HOT AND
MOSTLY DRY THROUGH THE WEEKEND WITH MODERATING TEMPERATURES AND
INCREASING PRECIPITATION CHANCES EARLY NEXT WEEK...WHICH IS WHAT WE
HAVE BEEN CARRYING IN THE EXTENDED FORECAST FOR THE PAST SEVERAL
DAYS NOW. WITH THIS IN MIND I DO NOT PLAN ON DEVIATING TOO MUCH FROM
PREVIOUS TRENDS IN THE FORECAST GRIDS. THROUGH THE WEEKEND THE
GFS/ECMWF KEEP THE CENTER OF THE UPPER RIDGE WEST OF THE STATE WITH
THE BEST SUBSIDENCE REMAINING WEST OF US AS WELL. WITH THIS IN MIND
I WILL KEEP THE SLIGHT CHANCE POPS INTO THE WEEKEND WITH CHANCE POPS
AS WE HEAD INTO THE FIRST HALF OF THE NEW WEEK.

20

&&

AVIATION...
06Z UPDATE...
LATEST AREA OBS SHOW LIFR CIGS ALREADY AT CARROLLTON /CTJ/ AND
NEWNAN /CCO/. THE WESTERLY FLOW SHOULD SPREAD AT LEAST IFR CIGS INTO
THE ATLANTA TAF SITES BY 09Z IF NOT SOONER. EXPECT A GRADUAL
IMPROVEMENT TO MVFR CIGS BY 13-14Z... THEN VFR BY 15-16Z. GFS AND
NAM MODELS SHOW A SUBTLE ACTIVE NW FLOW ALOFT THIS AFTERNOON...
WHICH WOULD SUPPORT DIURNAL CONVECTION BETWEEN 18-22Z TODAY. WILL
CONTINUE TO SHOW PROB30 -TSRA FOR THIS TIME PERIOD. LIGHT WSW WINDS
EARLY THIS MORNING WILL MIX DOWN MORE WNW BY 15-17Z AND INCREASE TO
AROUND 8-10KTS. EXPECT LIGHT WNW WINDS TONIGHT WITH ONLY SCT MVFR
LEVEL CLOUDS EXPECTED BY 09-10Z THU MORNING AT THIS TIME.

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON IFR/MVFR CIGS LATER THIS MORNING. HIGH CONFIDENCE ON ALL
OTHER ELEMENTS.

39

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          96  71  97  73 /  30  20  20  20
ATLANTA         92  75  94  76 /  30  20  20  20
BLAIRSVILLE     88  66  88  68 /  30  30  20  20
CARTERSVILLE    93  70  96  71 /  30  20  20  20
COLUMBUS        96  74  95  76 /  30  20  20  20
GAINESVILLE     93  73  94  74 /  30  20  20  20
MACON           96  72  97  74 /  30  20  20  20
ROME            94  71  96  71 /  30  20  20  20
PEACHTREE CITY  92  70  94  72 /  30  20  20  20
VIDALIA         96  74  98  76 /  30  20  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...39
LONG TERM....20
AVIATION...39






000
FXUS62 KCAE 200737
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
337 AM EDT WED AUG 20 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES THROUGH FRIDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE
WILL INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER RIDGE BUILDING TO THE WEST OF THE AREA TODAY. WARMING 850MB
TEMPERATURES AND LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN
TEMPERATURES A FEW DEGREES WARMER THAN YESTERDAY. ONLY SLIGHT
CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS DUE TO DRIER AIR AND
BUILDING RIDGE ALOFT. MODELS SOUNDINGS SUGGEST MODERATE
INSTABILITY GIVEN WARM SURFACE TEMPERATURES BUT A RELATIVELY HIGH
LFC/POSSIBLE CAP. STRONG LIFTING ALSO NOT EXPECTED.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
UPPER RIDGE CONTINUES CENTERED TO THE WEST OF THE AREA. MODELS
SUGGEST LOW LEVEL WARMING THROUGH THE PERIOD. TEMPERATURES LIKELY
NEAR 100 DEGREES. GUIDANCE INDICATES DEW POINTS MIXING DOWN INTO
THE MID TO UPPER 60S ACROSS THE NORTHERN AND WESTERN COUNTIES TO
NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS SHOULD KEEP HEAT
INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110F. ONLY SLIGHT
CHANCE OF SHOWERS/TSTMS EXPECTED DUE TO DRIER AIR AND BUILDING
RIDGE ALOFT.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS TO DOMINATE THE PERIOD...WITH POSSIBLE MVFR
CONDITIONS FROM 09Z-13Z AT ALL SITES.

MID AND UPPER LEVEL CLOUDS CONTINUE TO CROSS THE REGION WITH THE
MAIN CONCERN BEING FOG AROUND DAYBREAK. WITH LIGHT WINDS AND
REMAINING LOW LEVEL MOISTURE EXPECT VSBYS TO LOWER TO 4-5SM
BETWEEN 09Z AND 13Z. BEST CHANCE OF FOG WILL BE AT AGS/OGB WITH
LOWER CONFIDENCE AT CAE/CUB/DNL. FOG WHICH DEVELOPS WILL DISSIPATE
BY 13Z WITH ALL SITES VFR THROUGH THE REMAINDER OF THE PERIOD.
WINDS WILL BE WESTERLY AT 8 KNOTS OR LESS THROUGH THE PERIOD.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 200609
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
209 AM EDT WED AUG 20 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CONVECTION HAS ENDED ACROSS THE AREA AS NVA MOVES IN. EXPECT A
MAINLY DRY FORECAST FOR THE REMAINDER OF THE NIGHT. OVERNIGHT
LOWS IN THE LOWER 70S STILL LOOK REASONABLE.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS TO DOMINATE THE PERIOD...WITH POSSIBLE MVFR
CONDITIONS FROM 09Z-13Z AT ALL SITES.

MID AND UPPER LEVEL CLOUDS CONTINUE TO CROSS THE REGION WITH THE
MAIN CONCERN BEING FOG AROUND DAYBREAK. WITH LIGHT WINDS AND
REMAINING LOW LEVEL MOISTURE EXPECT VSBYS TO LOWER TO 4-5SM
BETWEEN 09Z AND 13Z. BEST CHANCE OF FOG WILL BE AT AGS/OGB WITH
LOWER CONFIDENCE AT CAE/CUB/DNL. FOG WHICH DEVELOPS WILL DISSIPATE
BY 13Z WITH ALL SITES VFR THROUGH THE REMAINDER OF THE PERIOD.
WINDS WILL BE WESTERLY AT 8 KNOTS OR LESS THROUGH THE PERIOD.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 200609
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
209 AM EDT WED AUG 20 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CONVECTION HAS ENDED ACROSS THE AREA AS NVA MOVES IN. EXPECT A
MAINLY DRY FORECAST FOR THE REMAINDER OF THE NIGHT. OVERNIGHT
LOWS IN THE LOWER 70S STILL LOOK REASONABLE.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS TO DOMINATE THE PERIOD...WITH POSSIBLE MVFR
CONDITIONS FROM 09Z-13Z AT ALL SITES.

MID AND UPPER LEVEL CLOUDS CONTINUE TO CROSS THE REGION WITH THE
MAIN CONCERN BEING FOG AROUND DAYBREAK. WITH LIGHT WINDS AND
REMAINING LOW LEVEL MOISTURE EXPECT VSBYS TO LOWER TO 4-5SM
BETWEEN 09Z AND 13Z. BEST CHANCE OF FOG WILL BE AT AGS/OGB WITH
LOWER CONFIDENCE AT CAE/CUB/DNL. FOG WHICH DEVELOPS WILL DISSIPATE
BY 13Z WITH ALL SITES VFR THROUGH THE REMAINDER OF THE PERIOD.
WINDS WILL BE WESTERLY AT 8 KNOTS OR LESS THROUGH THE PERIOD.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$








000
FXUS62 KCHS 200608
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
208 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
NOCTURNAL STABILIZATION HAS CAUSED SHOWER AND TSTM ACTIVITY TO
TAPER OFF LATE THIS EVENING. A TRAILING SHORTWAVE MOVING THROUGH
OVERNIGHT COULD SPUR AN ISOLATED SHOWER OR STORM OVER THE ATLANTIC
WATERS BUT MOST AREAS SHOULD BE DRY.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
RELATIVELY QUIET CONDITIONS EXPECTED THROUGH 06Z THU. ONLY AN
ISOLATED CHANCE FOR A SHOWER OR TSTM AT EITHER TERMINAL THIS
AFTERNOON BUT WE DID NOT INCLUDE ANY MENTION AT THIS TIME. VFR
OTHERWISE.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY NIGHT THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SW WINDS 10-20 KT WILL VEER TOWARD THE WEST AND WILL DIMINISH
SOMEWHAT LATER TONIGHT. COMBINED SEAS 2-3 FT WITHIN NEARSHORE
WATERS AND 4-5 FT BEYOND 20 NM WILL PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...JRL
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 200608
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
208 AM EDT WED AUG 20 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
NOCTURNAL STABILIZATION HAS CAUSED SHOWER AND TSTM ACTIVITY TO
TAPER OFF LATE THIS EVENING. A TRAILING SHORTWAVE MOVING THROUGH
OVERNIGHT COULD SPUR AN ISOLATED SHOWER OR STORM OVER THE ATLANTIC
WATERS BUT MOST AREAS SHOULD BE DRY.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
RELATIVELY QUIET CONDITIONS EXPECTED THROUGH 06Z THU. ONLY AN
ISOLATED CHANCE FOR A SHOWER OR TSTM AT EITHER TERMINAL THIS
AFTERNOON BUT WE DID NOT INCLUDE ANY MENTION AT THIS TIME. VFR
OTHERWISE.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY NIGHT THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SW WINDS 10-20 KT WILL VEER TOWARD THE WEST AND WILL DIMINISH
SOMEWHAT LATER TONIGHT. COMBINED SEAS 2-3 FT WITHIN NEARSHORE
WATERS AND 4-5 FT BEYOND 20 NM WILL PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...JRL
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...






000
FXUS62 KFFC 200538
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
138 AM EDT WED AUG 20 2014

.UPDATE...
/ISSUED AT 940 PM EDT TUE AUG 19 2014/
SHOWERS/THUNDERSTORMS HAVE DISSIPATED AND HAVE CONTINUED WITH LESS
THAN 20 PERCENT AFTER MIDNIGHT. A FEW MINOR TWEAKS TO OVERNIGHT
LOWS...OTHERWISE NO CHANGES.

41


.PREVIOUS...
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

.AVIATION...
06Z UPDATE...
LATEST AREA OBS SHOW LIFR CIGS ALREADY AT CARROLLTON /CTJ/ AND
NEWNAN /CCO/. THE WESTERLY FLOW SHOULD SPREAD AT LEAST IFR CIGS INTO
THE ATLANTA TAF SITES BY 09Z IF NOT SOONER. EXPECT A GRADUAL
IMPROVEMENT TO MVFR CIGS BY 13-14Z... THEN VFR BY 15-16Z. GFS AND
NAM MODELS SHOW A SUBTLE ACTIVE NW FLOW ALOFT THIS AFTERNOON...
WHICH WOULD SUPPORT DIURNAL CONVECTION BETWEEN 18-22Z TODAY. WILL
CONTINUE TO SHOW PROB30 -TSRA FOR THIS TIME PERIOD. LIGHT WSW WINDS
EARLY THIS MORNING WILL MIX DOWN MORE WNW BY 15-17Z AND INCREASE TO
AROUND 8-10KTS. EXPECT LIGHT WNW WINDS TONIGHT WITH ONLY SCT MVFR
LEVEL CLOUDS EXPECTED BY 09-10Z THU MORNING AT THIS TIME.

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON IFR/MVFR CIGS LATER THIS MORNING. HIGH CONFIDENCE ON ALL
OTHER ELEMENTS.

39

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...41/39
LONG TERM....TDP
AVIATION...39














000
FXUS62 KFFC 200538
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
138 AM EDT WED AUG 20 2014

.UPDATE...
/ISSUED AT 940 PM EDT TUE AUG 19 2014/
SHOWERS/THUNDERSTORMS HAVE DISSIPATED AND HAVE CONTINUED WITH LESS
THAN 20 PERCENT AFTER MIDNIGHT. A FEW MINOR TWEAKS TO OVERNIGHT
LOWS...OTHERWISE NO CHANGES.

41


.PREVIOUS...
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

.AVIATION...
06Z UPDATE...
LATEST AREA OBS SHOW LIFR CIGS ALREADY AT CARROLLTON /CTJ/ AND
NEWNAN /CCO/. THE WESTERLY FLOW SHOULD SPREAD AT LEAST IFR CIGS INTO
THE ATLANTA TAF SITES BY 09Z IF NOT SOONER. EXPECT A GRADUAL
IMPROVEMENT TO MVFR CIGS BY 13-14Z... THEN VFR BY 15-16Z. GFS AND
NAM MODELS SHOW A SUBTLE ACTIVE NW FLOW ALOFT THIS AFTERNOON...
WHICH WOULD SUPPORT DIURNAL CONVECTION BETWEEN 18-22Z TODAY. WILL
CONTINUE TO SHOW PROB30 -TSRA FOR THIS TIME PERIOD. LIGHT WSW WINDS
EARLY THIS MORNING WILL MIX DOWN MORE WNW BY 15-17Z AND INCREASE TO
AROUND 8-10KTS. EXPECT LIGHT WNW WINDS TONIGHT WITH ONLY SCT MVFR
LEVEL CLOUDS EXPECTED BY 09-10Z THU MORNING AT THIS TIME.

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON IFR/MVFR CIGS LATER THIS MORNING. HIGH CONFIDENCE ON ALL
OTHER ELEMENTS.

39

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...41/39
LONG TERM....TDP
AVIATION...39















000
FXUS62 KCAE 200221
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1021 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM WEDNESDAY MORNING/...
CONVECTION HAS ENDED ACROSS THE AREA AS NVA MOVES IN. EXPECT A
MAINLY DRY FORECAST FOR THE REMAINDER OF THE NIGHT. OVERNIGHT
LOWS IN THE LOWER 70S STILL LOOK REASONABLE.

&&

.SHORT TERM /8 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH EARLY TONIGHT...WITH POSSIBLE
MVFR VISIBILITIES FROM 09Z-13Z AT ALL SITES...THEN A RETURN TO VFR
THROUGH THE DAY WEDNESDAY.

OVERNIGHT THE WINDS WILL BECOME LIGHT AND VARIABLE. WITH SOME
LOW-LEVEL MOISTURE AROUND...AND WITH SKIES EXPECTED TO BECOME MAINLY
SCATTERED WITH HIGH LEVEL CLOUDINESS...GUIDANCE NUMBERS ARE
INDICATING VISIBILITIES DROPPING DOWN TO 4-5SM AT ALL SITES THROUGH
EARLY MORNING. MIXING AFTER SUNRISE SHOULD BRING VISIBILITIES BACK
UP TO P6SM BY 13Z. WINDS WILL BECOME WESTERLY AROUND 5 KTS THROUGH
THE DAY WEDNESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.

&&

$$









000
FXUS62 KCHS 200156
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
956 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
NOCTURNAL STABILIZATION HAS CAUSED SHOWER AND TSTM ACTIVITY TO
TAPER OFF LATE THIS EVENING. A TRAILING SHORTWAVE MOVING THROUGH
OVERNIGHT COULD SPUR AN ISOLATED SHOWER OR STORM OVER THE ATLANTIC
WATERS BUT MOST AREAS SHOULD BE DRY.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
UPSTREAM SHRA/TSRA IS EXPECTED TO FIZZLE BEFORE IMPACTING THE
TERMINALS EARLY TONIGHT...THUS WE/LL GO WITH A VFR FORECAST. THERE
MIGHT BE A LITTLE STRATUS AT KSAV LATE TONIGHT/WEDNESDAY MORNING
WITH A LOW END RISK FOR SUB-VFR CONDITIONS TO OCCUR. LITTLE TO NO
CHANCE FOR SHRA/TSRA AT EITHER AIRFIELD ON WEDNESDAY.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY NIGHT THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SW WINDS 10-20 KT WILL VEER TOWARD THE WEST AND WILL DIMINISH
SOMEWHAT LATER TONIGHT. COMBINED SEAS 2-3 FT WITHIN NEARSHORE
WATERS AND 4-5 FT BEYOND 20 NM WILL PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 200156
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
956 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
NOCTURNAL STABILIZATION HAS CAUSED SHOWER AND TSTM ACTIVITY TO
TAPER OFF LATE THIS EVENING. A TRAILING SHORTWAVE MOVING THROUGH
OVERNIGHT COULD SPUR AN ISOLATED SHOWER OR STORM OVER THE ATLANTIC
WATERS BUT MOST AREAS SHOULD BE DRY.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
UPSTREAM SHRA/TSRA IS EXPECTED TO FIZZLE BEFORE IMPACTING THE
TERMINALS EARLY TONIGHT...THUS WE/LL GO WITH A VFR FORECAST. THERE
MIGHT BE A LITTLE STRATUS AT KSAV LATE TONIGHT/WEDNESDAY MORNING
WITH A LOW END RISK FOR SUB-VFR CONDITIONS TO OCCUR. LITTLE TO NO
CHANCE FOR SHRA/TSRA AT EITHER AIRFIELD ON WEDNESDAY.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY NIGHT THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
SW WINDS 10-20 KT WILL VEER TOWARD THE WEST AND WILL DIMINISH
SOMEWHAT LATER TONIGHT. COMBINED SEAS 2-3 FT WITHIN NEARSHORE
WATERS AND 4-5 FT BEYOND 20 NM WILL PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...JRL
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...







000
FXUS62 KFFC 200142
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
940 PM EDT TUE AUG 19 2014

.UPDATE...
SHOWERS/THUNDERSTORMS HAVE DISSIPATED AND HAVE CONTINUED WITH LESS
THAN 20 PERCENT AFTER MIDNIGHT. A FEW MINOR TWEAKS TO OVERNIGHT
LOWS...OTHERWISE NO CHANGES.

41


.PREVIOUS...
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
00Z UPDATE...
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DISSIPATE BUT ISOLATED STORMS
MAY LINGER OVERNIGHT. SOME MVFR CLOUDS AND FOG POSSIBLE AT THE TAF
SITES TOWARD MORNING. OTHERWISE MORE DIURNAL CONVECTION EXPECTED FOR
TOMORROW. WINDS WILL BE MOSTLY LIGHT AND VARIABLE OVERNIGHT AND WEST
TO SOUTHWEST 10KT WEDNESDAY.


//ATL CONFIDENCE...00Z UPDATE...
MEDIUM ON MVFR CONDITIONS LATE TONIGHT. HIGH CONFIDENCE ON ALL OTHER
ELEMENTS.

41

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...41
LONG TERM....TDP
AVIATION...41












000
FXUS62 KFFC 200142
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
940 PM EDT TUE AUG 19 2014

.UPDATE...
SHOWERS/THUNDERSTORMS HAVE DISSIPATED AND HAVE CONTINUED WITH LESS
THAN 20 PERCENT AFTER MIDNIGHT. A FEW MINOR TWEAKS TO OVERNIGHT
LOWS...OTHERWISE NO CHANGES.

41


.PREVIOUS...
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
00Z UPDATE...
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DISSIPATE BUT ISOLATED STORMS
MAY LINGER OVERNIGHT. SOME MVFR CLOUDS AND FOG POSSIBLE AT THE TAF
SITES TOWARD MORNING. OTHERWISE MORE DIURNAL CONVECTION EXPECTED FOR
TOMORROW. WINDS WILL BE MOSTLY LIGHT AND VARIABLE OVERNIGHT AND WEST
TO SOUTHWEST 10KT WEDNESDAY.


//ATL CONFIDENCE...00Z UPDATE...
MEDIUM ON MVFR CONDITIONS LATE TONIGHT. HIGH CONFIDENCE ON ALL OTHER
ELEMENTS.

41

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...41
LONG TERM....TDP
AVIATION...41












000
FXUS62 KFFC 200142
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
940 PM EDT TUE AUG 19 2014

.UPDATE...
SHOWERS/THUNDERSTORMS HAVE DISSIPATED AND HAVE CONTINUED WITH LESS
THAN 20 PERCENT AFTER MIDNIGHT. A FEW MINOR TWEAKS TO OVERNIGHT
LOWS...OTHERWISE NO CHANGES.

41


.PREVIOUS...
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
00Z UPDATE...
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DISSIPATE BUT ISOLATED STORMS
MAY LINGER OVERNIGHT. SOME MVFR CLOUDS AND FOG POSSIBLE AT THE TAF
SITES TOWARD MORNING. OTHERWISE MORE DIURNAL CONVECTION EXPECTED FOR
TOMORROW. WINDS WILL BE MOSTLY LIGHT AND VARIABLE OVERNIGHT AND WEST
TO SOUTHWEST 10KT WEDNESDAY.


//ATL CONFIDENCE...00Z UPDATE...
MEDIUM ON MVFR CONDITIONS LATE TONIGHT. HIGH CONFIDENCE ON ALL OTHER
ELEMENTS.

41

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...41
LONG TERM....TDP
AVIATION...41












000
FXUS62 KFFC 200142
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
940 PM EDT TUE AUG 19 2014

.UPDATE...
SHOWERS/THUNDERSTORMS HAVE DISSIPATED AND HAVE CONTINUED WITH LESS
THAN 20 PERCENT AFTER MIDNIGHT. A FEW MINOR TWEAKS TO OVERNIGHT
LOWS...OTHERWISE NO CHANGES.

41


.PREVIOUS...
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
00Z UPDATE...
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DISSIPATE BUT ISOLATED STORMS
MAY LINGER OVERNIGHT. SOME MVFR CLOUDS AND FOG POSSIBLE AT THE TAF
SITES TOWARD MORNING. OTHERWISE MORE DIURNAL CONVECTION EXPECTED FOR
TOMORROW. WINDS WILL BE MOSTLY LIGHT AND VARIABLE OVERNIGHT AND WEST
TO SOUTHWEST 10KT WEDNESDAY.


//ATL CONFIDENCE...00Z UPDATE...
MEDIUM ON MVFR CONDITIONS LATE TONIGHT. HIGH CONFIDENCE ON ALL OTHER
ELEMENTS.

41

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...41
LONG TERM....TDP
AVIATION...41












000
FXUS62 KFFC 192344
AFDFFC

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
740 PM EDT TUE AUG 19 2014

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
00Z UPDATE...
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DISSIPATE BUT ISOLATED STORMS
MAY LINGER OVERNIGHT. SOME MVFR CLOUDS AND FOG POSSIBLE AT THE TAF
SITES TOWARD MORNING. OTHERWISE MORE DIURNAL CONVECTION EXPECTED FOR
TOMORROW. WINDS WILL BE MOSTLY LIGHT AND VARIABLE OVERNIGHT AND WEST
TO SOUTHWEST 10KT WEDNESDAY.


//ATL CONFIDENCE...00Z UPDATE...
MEDIUM ON MVFR CONDITIONS LATE TONIGHT. HIGH CONFIDENCE ON ALL OTHER
ELEMENTS.

41

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...RW
LONG TERM....TDP
AVIATION...41








000
FXUS62 KFFC 192344
AFDFFC

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
740 PM EDT TUE AUG 19 2014

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
00Z UPDATE...
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DISSIPATE BUT ISOLATED STORMS
MAY LINGER OVERNIGHT. SOME MVFR CLOUDS AND FOG POSSIBLE AT THE TAF
SITES TOWARD MORNING. OTHERWISE MORE DIURNAL CONVECTION EXPECTED FOR
TOMORROW. WINDS WILL BE MOSTLY LIGHT AND VARIABLE OVERNIGHT AND WEST
TO SOUTHWEST 10KT WEDNESDAY.


//ATL CONFIDENCE...00Z UPDATE...
MEDIUM ON MVFR CONDITIONS LATE TONIGHT. HIGH CONFIDENCE ON ALL OTHER
ELEMENTS.

41

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...RW
LONG TERM....TDP
AVIATION...41









000
FXUS62 KCHS 192323
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
723 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
EARLY TUESDAY EVENING...PER RECENT/EXPECTED RADAR TRENDS ADJUSTED
EVENING POPS. INITIALLY INCREASED PRECIPITATION COVERAGE INLAND
WITH LOWER POPS ELSEWHERE...THEN PUSHED HIGH CHANCE POPS TOWARD
THE UPPER GA AND SC COASTS WHILE GRADUALLY LOWERING INLAND POPS TO
ACCOUNT FOR DIURNAL TRENDS AS THE EVENING PROGRESSES. ASIDE FROM
THESE REFINEMENTS OVERALL FORECAST REASONING REMAINS ON TRACK
TONIGHT.

UNDER THE INFLUENCE OF SHORTWAVES HEADING TOWARD THE SC/NC COAST
AND APPROACHING THE REGION FROM THE WEST...SCATTERED/NUMEROUS SHOWERS/
THUNDERSTORMS WILL CONTINUE TO DEVELOP/ADVANCE ACROSS THE REGION
THROUGH THIS EVENING. UNTIL AFTER DARK...925-500 MB WINDS 20-30
KT/0-1 KM SHEAR 10-20 KT WILL SUPPORT MULTICELL THUNDERSTORMS
WHICH WILL MOVE QUICKLY TOWARD THE EAST WITHIN A THERMODYNAMIC
ENVIRONMENT FEATURING MLCAPES 1500-2500 J/KG AND DOWNDRAFT CAPES
RECOVERING 700-1100 J/KG. THUS...THE THREAT FOR ISOLATED DAMAGING
WIND GUSTS WILL CONTINUE THIS EVENING.

LATER THIS EVENING...DIURNAL STABILIZATION SHOULD PROMPT A DECREASE
IN THUNDERSTORMS COVERAGE/INTENSITY. HOWEVER...DUE TO THE
INFLUENCE OF THE TRAILING SHORTWAVE...EXTENDED SLIGHT
CHANCE/CHANCE POPS INTO THE OVERNIGHT. POPS SHOULD EVENTUALLY FALL
BELOW 15 PERCENT ALL AREAS BY LATE TONIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SUNDAY/...
UPSTREAM SHRA/TSRA IS EXPECTED TO FIZZLE BEFORE IMPACTING THE
TERMINALS EARLY TONIGHT...THUS WE/LL GO WITH A VFR FORECAST. THERE
MIGHT BE A LITTLE STRATUS AT KSAV LATE TONIGHT/WEDNESDAY MORNING
WITH A LOW END RISK FOR SUB-VFR CONDITIONS TO OCCUR. LITTLE TO NO
CHANCE FOR SHRA/TSRA AT EITHER AIRFIELD ON WEDNESDAY.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY NIGHT THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS ESPECIALLY THROUGH
THIS EVENING. OUTSIDE THUNDERSTORMS...SW WINDS 10-20 KT WILL VEER
TOWARD THE WEST AND WILL DIMINISH SOMEWHAT LATER TONIGHT. COMBINED
SEAS 2-3 FT WITHIN NEARSHORE WATERS AND 4-5 FT BEYOND 20 NM WILL
PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 192323
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
723 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
EARLY TUESDAY EVENING...PER RECENT/EXPECTED RADAR TRENDS ADJUSTED
EVENING POPS. INITIALLY INCREASED PRECIPITATION COVERAGE INLAND
WITH LOWER POPS ELSEWHERE...THEN PUSHED HIGH CHANCE POPS TOWARD
THE UPPER GA AND SC COASTS WHILE GRADUALLY LOWERING INLAND POPS TO
ACCOUNT FOR DIURNAL TRENDS AS THE EVENING PROGRESSES. ASIDE FROM
THESE REFINEMENTS OVERALL FORECAST REASONING REMAINS ON TRACK
TONIGHT.

UNDER THE INFLUENCE OF SHORTWAVES HEADING TOWARD THE SC/NC COAST
AND APPROACHING THE REGION FROM THE WEST...SCATTERED/NUMEROUS SHOWERS/
THUNDERSTORMS WILL CONTINUE TO DEVELOP/ADVANCE ACROSS THE REGION
THROUGH THIS EVENING. UNTIL AFTER DARK...925-500 MB WINDS 20-30
KT/0-1 KM SHEAR 10-20 KT WILL SUPPORT MULTICELL THUNDERSTORMS
WHICH WILL MOVE QUICKLY TOWARD THE EAST WITHIN A THERMODYNAMIC
ENVIRONMENT FEATURING MLCAPES 1500-2500 J/KG AND DOWNDRAFT CAPES
RECOVERING 700-1100 J/KG. THUS...THE THREAT FOR ISOLATED DAMAGING
WIND GUSTS WILL CONTINUE THIS EVENING.

LATER THIS EVENING...DIURNAL STABILIZATION SHOULD PROMPT A DECREASE
IN THUNDERSTORMS COVERAGE/INTENSITY. HOWEVER...DUE TO THE
INFLUENCE OF THE TRAILING SHORTWAVE...EXTENDED SLIGHT
CHANCE/CHANCE POPS INTO THE OVERNIGHT. POPS SHOULD EVENTUALLY FALL
BELOW 15 PERCENT ALL AREAS BY LATE TONIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SUNDAY/...
UPSTREAM SHRA/TSRA IS EXPECTED TO FIZZLE BEFORE IMPACTING THE
TERMINALS EARLY TONIGHT...THUS WE/LL GO WITH A VFR FORECAST. THERE
MIGHT BE A LITTLE STRATUS AT KSAV LATE TONIGHT/WEDNESDAY MORNING
WITH A LOW END RISK FOR SUB-VFR CONDITIONS TO OCCUR. LITTLE TO NO
CHANCE FOR SHRA/TSRA AT EITHER AIRFIELD ON WEDNESDAY.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY NIGHT THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS ESPECIALLY THROUGH
THIS EVENING. OUTSIDE THUNDERSTORMS...SW WINDS 10-20 KT WILL VEER
TOWARD THE WEST AND WILL DIMINISH SOMEWHAT LATER TONIGHT. COMBINED
SEAS 2-3 FT WITHIN NEARSHORE WATERS AND 4-5 FT BEYOND 20 NM WILL
PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...






000
FXUS62 KCAE 192318
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
718 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SCATTERED SHOWERS/THUNDERSTORMS CONTINUE ACROSS THE FORECAST AREA
EARLY THIS EVENING AS AN UPPER-LEVEL DISTURBANCE MOVES EAST. WILL
CONTINUE LOW CHANCE POPS UNTIL AROUND MIDNIGHT AS THE DISTURBANCE
MOVES EAST OF THE AREA. OVERNIGHT LOWS IN THE LOWER 70S LOOK
REASONABLE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH EARLY TONIGHT...WITH POSSIBLE
MVFR VISIBILITIES FROM 09Z-13Z AT ALL SITES...THEN A RETURN TO VFR
THROUGH THE DAY WEDNESDAY.

SURFACE TROUGH ACROSS THE AREA...IN COMBINATION WITH GOOD HEATING
AND A SHORTWAVE MOVING THROUGH...HAVE PRODUCED SCATTERED SHOWERS
AND THUNDERSTORMS ONCE AGAIN. CHANCE OF ANY ONE CELL IMPACTING A
TAF SITE IS SMALL...SO WILL NOT INCLUDE AT THIS TIME. WILL AMEND
AS NECESSARY THROUGH THE EVENING.

OVERNIGHT THE WINDS WILL DIMINISH TO AROUND 5 KTS...THEN SHOULD
BECOME LIGHT AND VARIABLE BY 09Z. WITH SOME LOW-LEVEL MOISTURE
AROUND...AND WITH ONLY SCATTERED HIGH LEVEL CLOUDINESS...GUIDANCE
NUMBERS ARE INDICATING VISIBILITIES DROPPING DOWN TO 4-5SM AT ALL
SITES THROUGH EARLY MORNING. MIXING AFTER SUNRISE SHOULD BRING
VISIBILITIES BACK UP TO P6SM BY 13Z. WINDS WILL BECOME WESTERLY
AROUND 5 KTS THROUGH THE DAY WEDNESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$











000
FXUS62 KCAE 192318
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
718 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SCATTERED SHOWERS/THUNDERSTORMS CONTINUE ACROSS THE FORECAST AREA
EARLY THIS EVENING AS AN UPPER-LEVEL DISTURBANCE MOVES EAST. WILL
CONTINUE LOW CHANCE POPS UNTIL AROUND MIDNIGHT AS THE DISTURBANCE
MOVES EAST OF THE AREA. OVERNIGHT LOWS IN THE LOWER 70S LOOK
REASONABLE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH EARLY TONIGHT...WITH POSSIBLE
MVFR VISIBILITIES FROM 09Z-13Z AT ALL SITES...THEN A RETURN TO VFR
THROUGH THE DAY WEDNESDAY.

SURFACE TROUGH ACROSS THE AREA...IN COMBINATION WITH GOOD HEATING
AND A SHORTWAVE MOVING THROUGH...HAVE PRODUCED SCATTERED SHOWERS
AND THUNDERSTORMS ONCE AGAIN. CHANCE OF ANY ONE CELL IMPACTING A
TAF SITE IS SMALL...SO WILL NOT INCLUDE AT THIS TIME. WILL AMEND
AS NECESSARY THROUGH THE EVENING.

OVERNIGHT THE WINDS WILL DIMINISH TO AROUND 5 KTS...THEN SHOULD
BECOME LIGHT AND VARIABLE BY 09Z. WITH SOME LOW-LEVEL MOISTURE
AROUND...AND WITH ONLY SCATTERED HIGH LEVEL CLOUDINESS...GUIDANCE
NUMBERS ARE INDICATING VISIBILITIES DROPPING DOWN TO 4-5SM AT ALL
SITES THROUGH EARLY MORNING. MIXING AFTER SUNRISE SHOULD BRING
VISIBILITIES BACK UP TO P6SM BY 13Z. WINDS WILL BECOME WESTERLY
AROUND 5 KTS THROUGH THE DAY WEDNESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$










000
FXUS62 KCHS 192158
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
558 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
EARLY TUESDAY EVENING...PER RECENT/EXPECTED RADAR TRENDS ADJUSTED
EVENING POPS. INITIALLY INCREASED PRECIPITATION COVERAGE INLAND
WITH LOWER POPS ELSEWHERE...THEN PUSHED HIGH CHANCE POPS TOWARD
THE UPPER GA AND SC COASTS WHILE GRADUALLY LOWERING INLAND POPS TO
ACCOUNT FOR DIURNAL TRENDS AS THE EVENING PROGRESSES. ASIDE FROM
THESE REFINEMENTS OVERALL FORECAST REASONING REMAINS ON TRACK
TONIGHT.

UNDER THE INFLUENCE OF SHORTWAVES HEADING TOWARD THE SC/NC COAST
AND APPROACHING THE REGION FROM THE WEST...SCATTERED/NUMEROUS SHOWERS/
THUNDERSTORMS WILL CONTINUE TO DEVELOP/ADVANCE ACROSS THE REGION
THROUGH THIS EVENING. UNTIL AFTER DARK...925-500 MB WINDS 20-30
KT/0-1 KM SHEAR 10-20 KT WILL SUPPORT MULTICELL THUNDERSTORMS
WHICH WILL MOVE QUICKLY TOWARD THE EAST WITHIN A THERMODYNAMIC
ENVIRONMENT FEATURING MLCAPES 1500-2500 J/KG AND DOWNDRAFT CAPES
RECOVERING 700-1100 J/KG. THUS...THE THREAT FOR ISOLATED DAMAGING
WIND GUSTS WILL CONTINUE THIS EVENING.

LATER THIS EVENING...DIURNAL STABILIZATION SHOULD PROMPT A DECREASE
IN THUNDERSTORMS COVERAGE/INTENSITY. HOWEVER...DUE TO THE
INFLUENCE OF THE TRAILING SHORTWAVE...EXTENDED SLIGHT
CHANCE/CHANCE POPS INTO THE OVERNIGHT. POPS SHOULD EVENTUALLY FALL
BELOW 15 PERCENT ALL AREAS BY LATE TONIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP IN THE
VICINITY OF THE TERMINALS WELL INTO THIS EVENING. MAINTAINED
CBS/VCTS BUT THE POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY/SHIFTING
WINDS AND FLIGHT RESTRICTIONS REMAIN UNCERTAIN. WILL AMEND TAFS
AS NEEDED BASED ON NEAR TERM CONVECTIVE TRENDS.

OUTSIDE THUNDERSTORMS...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS ESPECIALLY THROUGH
THIS EVENING. OUTSIDE THUNDERSTORMS...SW WINDS 10-20 KT WILL VEER
TOWARD THE WEST AND WILL DIMINISH SOMEWHAT LATER TONIGHT. COMBINED
SEAS 2-3 FT WITHIN NEARSHORE WATERS AND 4-5 FT BEYOND 20 NM WILL
PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...SPR/WMS
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 192158
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
558 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
EARLY TUESDAY EVENING...PER RECENT/EXPECTED RADAR TRENDS ADJUSTED
EVENING POPS. INITIALLY INCREASED PRECIPITATION COVERAGE INLAND
WITH LOWER POPS ELSEWHERE...THEN PUSHED HIGH CHANCE POPS TOWARD
THE UPPER GA AND SC COASTS WHILE GRADUALLY LOWERING INLAND POPS TO
ACCOUNT FOR DIURNAL TRENDS AS THE EVENING PROGRESSES. ASIDE FROM
THESE REFINEMENTS OVERALL FORECAST REASONING REMAINS ON TRACK
TONIGHT.

UNDER THE INFLUENCE OF SHORTWAVES HEADING TOWARD THE SC/NC COAST
AND APPROACHING THE REGION FROM THE WEST...SCATTERED/NUMEROUS SHOWERS/
THUNDERSTORMS WILL CONTINUE TO DEVELOP/ADVANCE ACROSS THE REGION
THROUGH THIS EVENING. UNTIL AFTER DARK...925-500 MB WINDS 20-30
KT/0-1 KM SHEAR 10-20 KT WILL SUPPORT MULTICELL THUNDERSTORMS
WHICH WILL MOVE QUICKLY TOWARD THE EAST WITHIN A THERMODYNAMIC
ENVIRONMENT FEATURING MLCAPES 1500-2500 J/KG AND DOWNDRAFT CAPES
RECOVERING 700-1100 J/KG. THUS...THE THREAT FOR ISOLATED DAMAGING
WIND GUSTS WILL CONTINUE THIS EVENING.

LATER THIS EVENING...DIURNAL STABILIZATION SHOULD PROMPT A DECREASE
IN THUNDERSTORMS COVERAGE/INTENSITY. HOWEVER...DUE TO THE
INFLUENCE OF THE TRAILING SHORTWAVE...EXTENDED SLIGHT
CHANCE/CHANCE POPS INTO THE OVERNIGHT. POPS SHOULD EVENTUALLY FALL
BELOW 15 PERCENT ALL AREAS BY LATE TONIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP IN THE
VICINITY OF THE TERMINALS WELL INTO THIS EVENING. MAINTAINED
CBS/VCTS BUT THE POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY/SHIFTING
WINDS AND FLIGHT RESTRICTIONS REMAIN UNCERTAIN. WILL AMEND TAFS
AS NEEDED BASED ON NEAR TERM CONVECTIVE TRENDS.

OUTSIDE THUNDERSTORMS...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS ESPECIALLY THROUGH
THIS EVENING. OUTSIDE THUNDERSTORMS...SW WINDS 10-20 KT WILL VEER
TOWARD THE WEST AND WILL DIMINISH SOMEWHAT LATER TONIGHT. COMBINED
SEAS 2-3 FT WITHIN NEARSHORE WATERS AND 4-5 FT BEYOND 20 NM WILL
PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...SPR/WMS
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 191955
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
355 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
UNDER THE INFLUENCE OF SHORTWAVES HEADING TOWARD THE SC/NC COAST
AND APPROACHING THE REGION FROM THE WEST...AT LEAST SCATTERED
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE REGION
THROUGH THIS EVENING. TO START...925-500 MB WINDS 20-30 KT/0-1 KM
SHEAR 10-15 KT WILL SUPPORT MULTICELL THUNDERSTORMS WHICH WILL MOVE
QUICKLY TOWARD THE EAST WITHIN A THERMODYNAMIC ENVIRONMENT
FEATURING MLCAPES INCREASING TO 2000-3000 J/KG AND DOWNDRAFT
CAPES RECOVERING TO AROUND 1000 J/KG IN THE WAKE OF EARLIER
CONVECTION. THUS...THE THREAT FOR ISOLATED DAMAGING WIND GUSTS
WILL CONTINUE THIS EVENING.

LATE THIS EVENING...DIURNAL STABILIZATION SHOULD PROMPT A DECREASE
IN THUNDERSTORMS COVERAGE/INTENSITY. HOWEVER...DUE TO THE
INFLUENCE OF THE TRAILING SHORTWAVE...EXTENDED SLIGHT
CHANCE/CHANCE POPS INTO THE OVERNIGHT. POPS SHOULD EVENTUALLY FALL
BELOW 15 PERCENT ALL AREAS BY LATE TONIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP IN THE
VICINITY OF THE TERMINALS WELL INTO THIS EVENING. MAINTAINED
CBS/VCTS BUT THE POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY/SHIFTING
WINDS AND FLIGHT RESTRICTIONS REMAIN UNCERTAIN. WILL AMEND TAFS
AS NEEDED BASED ON NEAR TERM CONVECTIVE TRENDS.

OUTSIDE THUNDERSTORMS...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS ESPECIALLY THROUGH
THIS EVENING. OUTSIDE THUNDERSTORMS...SW WINDS 15-20 KT WILL VEER
TOWARD THE WEST AND WILL DIMINISH SOMEWHAT LATER TONIGHT. SEAS
2-3 FT WITHIN NEARSHORE WATERS AND 4-5 FT BEYOND 20 NM WILL PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...SPR/WMS
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 191955
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
355 PM EDT TUE AUG 19 2014

.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF THE REGION AND A
TROUGH OF LOW PRESSURE WILL PREVAIL INLAND THROUGH FRIDAY. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
UNDER THE INFLUENCE OF SHORTWAVES HEADING TOWARD THE SC/NC COAST
AND APPROACHING THE REGION FROM THE WEST...AT LEAST SCATTERED
SHOWERS/THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE REGION
THROUGH THIS EVENING. TO START...925-500 MB WINDS 20-30 KT/0-1 KM
SHEAR 10-15 KT WILL SUPPORT MULTICELL THUNDERSTORMS WHICH WILL MOVE
QUICKLY TOWARD THE EAST WITHIN A THERMODYNAMIC ENVIRONMENT
FEATURING MLCAPES INCREASING TO 2000-3000 J/KG AND DOWNDRAFT
CAPES RECOVERING TO AROUND 1000 J/KG IN THE WAKE OF EARLIER
CONVECTION. THUS...THE THREAT FOR ISOLATED DAMAGING WIND GUSTS
WILL CONTINUE THIS EVENING.

LATE THIS EVENING...DIURNAL STABILIZATION SHOULD PROMPT A DECREASE
IN THUNDERSTORMS COVERAGE/INTENSITY. HOWEVER...DUE TO THE
INFLUENCE OF THE TRAILING SHORTWAVE...EXTENDED SLIGHT
CHANCE/CHANCE POPS INTO THE OVERNIGHT. POPS SHOULD EVENTUALLY FALL
BELOW 15 PERCENT ALL AREAS BY LATE TONIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY...SHORTWAVE ENERGY WILL BE EXITING THE SOUTHEAST
COASTLINE DURING THE MORNING HOURS...LEAVING A SWATH OF NEGATIVE
VORTICITY ADVECTION IN ITS WAKE. THE SEABREEZE WILL BE PINNED TO
THE COAST THROUGH THE AFTERNOON BY SOLID WEST FLOW...ALLOWING
DEWPOINTS TO FALL TO 70 OR LESS WELL INLAND. AS A RESULT OF BOTH
WEAKER ENERGY ALOFT AND OFFSHORE WINDS....NUMERICAL MODEL
SOLUTIONS ARE RATHER CONSERVATIVE WITH THUNDERSTORM COVERAGE.
PREFER TO INDICATE ONLY A SLIGHT CHANCE FOR
THUNDERSTORMS...ACCOUNTING FOR SOME FORCING FROM A PERSISTENT
INLAND SURFACE TROUGH. TEMPERATURES WILL WARM WELL ABOVE SEASONAL
NORMALS...DUE TO BOTH THE STALLED SEABREEZE AND A STRENGTHENING
RIDGE CENTERED OVER THE GULF COAST STATES. HIGH TEMPERATURES WILL
RISE INTO THE MID TO UPPER 90S...WITH COASTAL AREAS LIKELY ABLE TO
REACH AT LEAST THE LOWER 90S. HEAT INDEX VALUES WILL BE IN THE 105
TO 109 DEGREE RANGE.

THURSDAY...AN IMPRESSIVE UPPER RIDGE WILL LIFT SLIGHTLY AND BUILD
INTO THE FORECAST AREA AS THE DAY PROGRESSES. THE SHIFT IN THE MID
AND UPPER LEVEL PATTERN WILL SUPPORT A DOWNSLOPE FLOW THAT WILL
CONTRIBUTE TO EVEN HOTTER TEMPERATURES THURSDAY
AFTERNOON...RANGING FROM THE UPPER 90S TO AROUND 100 DEGREES AWAY
FROM THE LOCALLY COOLER COASTLINE. HEAT INDICES WILL APPROACH
ADVISORY LEVELS AND PEAK AT 108 TO 110 DEGREES...MITIGATED ONLY BY
DEWPOINTS MIXING INTO TO THE UPPER 60S TO AROUND 70 INLAND AREAS.
MODEL SOLUTIONS ONCE AGAIN SUGGEST FAIRLY LIMITED CONVECTIVE
COVERAGE DURING THE NORMALLY FAVORED AFTERNOON HOURS. THE
SEABREEZE SHOULD MAKE BETTER PROGRESS INLAND DUE TO WEAKER LOW/MID
LEVEL FLOW...AND WILL INDICATE ONLY SLIGHT CHANCE POPS ALONG AND
INLAND OF THE SEABREEZE THURSDAY AFTERNOON. BOTH THE 12Z GFS AND
12Z NAM SUGGEST THE BEST THUNDERSTORM POTENTIAL COULD ACTUALLY
OCCUR OVERNIGHT...AS SHORTWAVE ENERGY TRACKS INTO THE CAROLINAS
ALONG THE PERIPHERY OF THE UPPER RIDGE AND DEEPER MOISTURE
STRETCHES SOUTHWARD. WILL ONLY ADVERTISE A SLIGHT CHANCE FOR
SHOWERS/THUNDERSTORMS ACROSS THE CHARLESTON TRI COUNTY AREA AFTER
SUNSET TO BLEND WITH A MUCH DRIER ECMWF SOLUTION.

FRIDAY...SHORTWAVE ENERGY WILL CONTINUE TO SLIP SOUTHWARD DOWN THE
COASTLINE...POSSIBLY STRENGTHENING THE SURFACE TROUGH AND ALLOWING
IT TO SHIFT CLOSER TO THE COASTLINE. THUNDERSTORM COVERAGE STILL
DOES NOT LOOK IMPRESSIVE...SO WILL CONTINUE TO ADVERTISE ISOLATED
CONVECTION DURING THE AFTERNOON HOURS...ENHANCED SLIGHTLY IF THE
SURFACE TROUGH INCREASES FORCING FOR ASCENT. HIGH TEMPERATURES
COULD MODERATE A DEGREE OR TWO...YET STILL RISE WELL ABOVE
SEASONAL NORMALS INTO THE MID TO UPPER 90S INLAND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP IN THE
VICINITY OF THE TERMINALS WELL INTO THIS EVENING. MAINTAINED
CBS/VCTS BUT THE POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY/SHIFTING
WINDS AND FLIGHT RESTRICTIONS REMAIN UNCERTAIN. WILL AMEND TAFS
AS NEEDED BASED ON NEAR TERM CONVECTIVE TRENDS.

OUTSIDE THUNDERSTORMS...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED
WEDNESDAY THROUGH FRIDAY. INCREASING CHANCES FOR FLIGHT
RESTRICTIONS SATURDAY INTO SUNDAY AS A FRONT DROPS THROUGH THE
REGION. LOW CEILINGS AND/OR VSBYS ARE POSSIBLE WITH THE FRONT...AS
WELL AS INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS ESPECIALLY THROUGH
THIS EVENING. OUTSIDE THUNDERSTORMS...SW WINDS 15-20 KT WILL VEER
TOWARD THE WEST AND WILL DIMINISH SOMEWHAT LATER TONIGHT. SEAS
2-3 FT WITHIN NEARSHORE WATERS AND 4-5 FT BEYOND 20 NM WILL PREVAIL.

SOUTHWEST FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY...BEFORE
WINDS BECOME NORTHEAST OR EAST/NORTHEAST BEHIND A COLD FRONT OVER
THE WEEKEND. OCCASIONAL WIND SURGES ARE POSSIBLE...ALTHOUGH WINDS
IN GENERAL WILL BE LESS THAN 15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...WMS
LONG TERM...JRL
AVIATION...SPR/WMS
MARINE...SPR/WMS
CLIMATE...
EQUIPMENT...







000
FXUS62 KFFC 191933
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
333 PM EDT TUE AUG 19 2014

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
SCATTERED SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS PARTS OF THE
AREA THIS AFTERNOON IN ASSOCIATION WITH A PASSING SHORTWAVE. A FEW
OF THESE STORMS HAVE BEEN ON THE STRONG SIDE...BUT THE MOST
SIGNIFICANT CONVECTION HAS REMAINED JUST SOUTH OF THE CWA. THESE
SHOWERS AND THUNDERSTORMS SHOULD DIMINISH AFTER SUNSET THIS EVENING.
SOME STORMS COULD APPROACH SEVERE LIMITS BEFORE THEY DISSIPATE WITH
THE MAIN HAZARDS BEING GUSTY WINDS...FREQUENT LIGHTNING...AND HEAVY
RAINFALL.

IT LOOKS LIKE WE WILL SEE ONE MORE DAY WITH SOME SHOWERS AND
THUNDERSTORMS AS A RELATIVELY WEAK SHORTWAVE WILL PASS ACROSS NORTH
GEORGIA AND A SHEAR AXIS SETS UP ACROSS CENTRAL GEORGIA TOMORROW. AS
HAS BEEN THE CASE TODAY...MOST OF THESE STORMS SHOULD REMAIN BELOW
SEVERE LIMITS. A BRIEF SEVERE STORM CANNOT BE RULED OUT WITH GUSTY
WINDS...HEAVY RAINFALL..AND FREQUENT LIGHTNING. LESS COVERAGE IS
EXPECTED TOMORROW AS THE UPPER RIDGE TO THE WEST STARTS TO BUILD
IN...THUS ALLOWING HIGHS ACROSS MUCH OF THE AREA TO REACH WELL INTO
THE 90S. THOSE HOT TEMPERATURES WILL JUST BE A PRECURSOR TO WHAT CAN
BE EXPECTED FOR THE REST OF THE WEEK.

RW

.LONG TERM /THURSDAY THROUGH TUESDAY/...
NOT MUCH CHANGE TO THE EXTENDED THIS AFTERNOON. DEFINITELY STILL
CONCERNED ABOUT THE HEAT FOR THE NEXT FEW DAYS AND WE ARE FLIRTING
WITH HEAT ADVISORY CRITERIA. CONFIDENCE NOT QUITE HIGH ENOUGH IN
DEWPOINTS ON FRIDAY AT THIS TIME BUT WILL REEVALUATE OVER THE NEXT
COUPLE OF DAYS. UPPER RIDGE SHOULD KEEP MOST POPS TO OUR EAST BUT
KEPT SLIGHT CHANCE AFTERNOON THUNDER JUST TO COVER THE TYPICAL
DIURNAL CONVECTION...ESPECIALLY GIVEN THE AMOUNT OF HEAT AND
MOISTURE THAT WILL BE ACROSS THE AREA. SEE PREVIOUS DISCUSSION
BELOW.

TDP

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST
WEST OF THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER
MISSISSIPPI VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE
RIDGE CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE
PULLING POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT
CHANCES WILL BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-
EAST GRADIENT AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO
TURN EASTERLY BY LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF
THE EDGE OFF OF THE HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
18Z UPDATE...
A FEW SCATTERED SHOWERS HAVE DEVELOPED IN PARTS OF NORTHWEST
GEORGIA THIS AFTERNOON. EXPECT ISOLATED ACTIVITY TO CONTINUE ACROSS THIS
AREA PRIOR TO SUNSET...SO HAVE INCLUDED VCSH AT METRO TAF SITES TO
ACCOUNT FOR THESE. SOME MVFR FOG IS POSSIBLE AT TAF SITES
OVERNIGHT. OTHERWISE...THE REST OF THE PERIOD LOOKS QUIET.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE CONVECTIVE ACTIVITY. HIGH CONFIDENCE ON ALL
OTHER ELEMENTS.

RW

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          72  94  74  98 /  20  30  20  20
ATLANTA         73  93  75  95 /  20  30  20  20
BLAIRSVILLE     65  86  68  89 /  20  30  20  20
CARTERSVILLE    72  94  71  95 /  20  30  20  20
COLUMBUS        74  95  76  97 /  20  30  20  20
GAINESVILLE     71  92  73  94 /  20  30  20  20
MACON           73  96  75  98 /  20  30  20  20
ROME            71  95  71  95 /  20  30  20  20
PEACHTREE CITY  72  94  73  95 /  20  30  20  20
VIDALIA         74  95  77  97 /  30  30  20  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...RW
LONG TERM....TDP
AVIATION...RW






000
FXUS62 KCAE 191824
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
224 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPPER LEVEL DISTURBANCE AND ASSOCIATED CLOUDINESS AND LIGHT SHOWER
ACTIVITY NOW CURRENTLY MOVING EAST ACROSS THE EAST FA...LEADING TO
GOOD COVERAGE OF SHOWERS AND THUNDERSTORMS MAINLY E/NE FA IN THE
NEAR TERM THRU MID AFTN. ADDITIONAL ACTIVITY DEVELOPING NEAR AND
BEHIND IT ALONG A SURFACE TROUGH OR LOW LEVEL CONVERGENCE ZONE
ACROSS W NC AND UPSTATE SC LOOKS TO SWING EAST ACROSS THE NORTHERN
HALF OF THE FA LATER THIS AFTERNOON AND EARLY EVENING. A SECOND
VORT MAX...CURRENTLY OVER N AL/NW GA...WILL SHIFT SE ACROSS CENT
GA TO S SC LATE TODAY AND THIS EVENING. SCATTERED SHOWERS AND
THUNDERSTORMS CURRENTLY DEVELOPING AHEAD OF THIS FEATURE OVER
PORTIONS OF N AND CENT GA...AND APPEARS COULD AFFECT THE CENTRAL
AND SOUTHERN CSRA BY LATE AFTERNOON. AN OUTFLOW BOUNDARY FROM
CONVECTION NEAR SE GA/SRN SC COULD ALSO POSSIBLY PROMOTE SOME
ACTIVITY ACROSS THE S/SE FA. SO...ALL IN ALL...THINK CHANCE POPS
WILL GENERALLY SUFFICE ACROSS MOST OF THE FA INTO THIS EVENING.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

STRONG HEATING AND CONVERGENCE INTO A LEE-SIDE TROUGH SHOULD HELP
SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE OF DIMINISHED MOISTURE BEHIND THE
SHORTWAVE TROUGH THAT PASSED EAST OF THE AREA EARLY THIS
AFTERNOON. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD
REMAIN WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A
DEEP LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. STRONG MIXING WILL BRING GUSTY WINDS THIS
AFTERNOON. USED THE GFS LAMP AND NAM BUFKIT MOMENTUM-TRANSFER
TOOL FOR THE WIND GUST FORECAST. DRYING ALOFT AND LINGERING LOW-
LEVEL MOISTURE PLUS NOCTURNAL COOLING MAY HELP SUPPORT FOG
DURING THE EARLY MORNING HOURS WEDNESDAY. MOST OF THE NAM AND GFS
MOS INDICATE MVFR FOG. HOWEVER...FOG WILL LIKELY BE LIMITED BY
SOME MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$









000
FXUS62 KCAE 191824
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
224 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPPER LEVEL DISTURBANCE AND ASSOCIATED CLOUDINESS AND LIGHT SHOWER
ACTIVITY NOW CURRENTLY MOVING EAST ACROSS THE EAST FA...LEADING TO
GOOD COVERAGE OF SHOWERS AND THUNDERSTORMS MAINLY E/NE FA IN THE
NEAR TERM THRU MID AFTN. ADDITIONAL ACTIVITY DEVELOPING NEAR AND
BEHIND IT ALONG A SURFACE TROUGH OR LOW LEVEL CONVERGENCE ZONE
ACROSS W NC AND UPSTATE SC LOOKS TO SWING EAST ACROSS THE NORTHERN
HALF OF THE FA LATER THIS AFTERNOON AND EARLY EVENING. A SECOND
VORT MAX...CURRENTLY OVER N AL/NW GA...WILL SHIFT SE ACROSS CENT
GA TO S SC LATE TODAY AND THIS EVENING. SCATTERED SHOWERS AND
THUNDERSTORMS CURRENTLY DEVELOPING AHEAD OF THIS FEATURE OVER
PORTIONS OF N AND CENT GA...AND APPEARS COULD AFFECT THE CENTRAL
AND SOUTHERN CSRA BY LATE AFTERNOON. AN OUTFLOW BOUNDARY FROM
CONVECTION NEAR SE GA/SRN SC COULD ALSO POSSIBLY PROMOTE SOME
ACTIVITY ACROSS THE S/SE FA. SO...ALL IN ALL...THINK CHANCE POPS
WILL GENERALLY SUFFICE ACROSS MOST OF THE FA INTO THIS EVENING.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

STRONG HEATING AND CONVERGENCE INTO A LEE-SIDE TROUGH SHOULD HELP
SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE OF DIMINISHED MOISTURE BEHIND THE
SHORTWAVE TROUGH THAT PASSED EAST OF THE AREA EARLY THIS
AFTERNOON. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD
REMAIN WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A
DEEP LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. STRONG MIXING WILL BRING GUSTY WINDS THIS
AFTERNOON. USED THE GFS LAMP AND NAM BUFKIT MOMENTUM-TRANSFER
TOOL FOR THE WIND GUST FORECAST. DRYING ALOFT AND LINGERING LOW-
LEVEL MOISTURE PLUS NOCTURNAL COOLING MAY HELP SUPPORT FOG
DURING THE EARLY MORNING HOURS WEDNESDAY. MOST OF THE NAM AND GFS
MOS INDICATE MVFR FOG. HOWEVER...FOG WILL LIKELY BE LIMITED BY
SOME MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$










000
FXUS62 KCHS 191804
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
204 PM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY TUESDAY AFTERNOON...A QLCS WITH A HISTORY OF SCATTERED WIND
DAMAGE WAS CROSSING THE SAVANNAH RIVER AND WAS HEADING E/NE TOWARD
SC LOCATIONS ALONG/E OF I-95...PERHAPS AS FAR NORTH AS THE
CHARLESTON TRI-COUNTY REGION...AND ADJACENT COASTAL WATERS. ALONG
THE OUTFLOW TRAILING THIS THUNDERSTORM COMPLEX...ADDITIONAL
MULTICELL THUNDERSTORMS HAD DEVELOPED AND WERE ADVANCING TOWARD SE
GA LOCALES ALONG THE ALTAMAHA RIVER.

MEANWHILE...THUNDERSTORMS ASSOCIATED WITH THE MIDLANDS SHORTWAVE
HAD THUS FAR REMAINED NORTH OF THE REGION...BUT SCATTERED
THUNDERSTORMS COULD EXPAND SOUTH INTO SC COUNTIES THIS AFTERNOON.

ADJUSTED AFTERNOON POP FORECASTS TO ACCOUNT FOR THESE TRENDS.
ALSO...COMPLETED SIGNIFICANT TEMPERATURE ADJUSTMENTS TO ACCOUNT
FOR IMPACTS OF CLOUDS/THUNDERSTORMS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
TONIGHT...TAIL END OF LEAD SHORTWAVE AND A SECONDARY/FOLLOWING
WILL EXTEND THE DURATION OF SLIGHT CHANCE/CHANCE POPS AT LEAST .
SHORTWAVE UPPER DISTURBANCE WILL FOLLOW THE LEAD SHORT WAVE AND
MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET MAINLY
ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD QUIET
DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY
AROUND SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS ARE
HIGH...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS THIS AFTERNOON.
OUTSIDE THUNDERSTORMS...SW WINDS 15-20 KT AND SEAS 2-3 FT WITHIN
NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. OUTSIDE THUNDERSTORMS...
ELEVATED W/SW WINDS AND SIMILAR SEAS WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 191804
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
204 PM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY TUESDAY AFTERNOON...A QLCS WITH A HISTORY OF SCATTERED WIND
DAMAGE WAS CROSSING THE SAVANNAH RIVER AND WAS HEADING E/NE TOWARD
SC LOCATIONS ALONG/E OF I-95...PERHAPS AS FAR NORTH AS THE
CHARLESTON TRI-COUNTY REGION...AND ADJACENT COASTAL WATERS. ALONG
THE OUTFLOW TRAILING THIS THUNDERSTORM COMPLEX...ADDITIONAL
MULTICELL THUNDERSTORMS HAD DEVELOPED AND WERE ADVANCING TOWARD SE
GA LOCALES ALONG THE ALTAMAHA RIVER.

MEANWHILE...THUNDERSTORMS ASSOCIATED WITH THE MIDLANDS SHORTWAVE
HAD THUS FAR REMAINED NORTH OF THE REGION...BUT SCATTERED
THUNDERSTORMS COULD EXPAND SOUTH INTO SC COUNTIES THIS AFTERNOON.

ADJUSTED AFTERNOON POP FORECASTS TO ACCOUNT FOR THESE TRENDS.
ALSO...COMPLETED SIGNIFICANT TEMPERATURE ADJUSTMENTS TO ACCOUNT
FOR IMPACTS OF CLOUDS/THUNDERSTORMS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
TONIGHT...TAIL END OF LEAD SHORTWAVE AND A SECONDARY/FOLLOWING
WILL EXTEND THE DURATION OF SLIGHT CHANCE/CHANCE POPS AT LEAST .
SHORTWAVE UPPER DISTURBANCE WILL FOLLOW THE LEAD SHORT WAVE AND
MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET MAINLY
ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD QUIET
DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY
AROUND SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS ARE
HIGH...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS THIS AFTERNOON.
OUTSIDE THUNDERSTORMS...SW WINDS 15-20 KT AND SEAS 2-3 FT WITHIN
NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. OUTSIDE THUNDERSTORMS...
ELEVATED W/SW WINDS AND SIMILAR SEAS WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 191804
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
204 PM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY TUESDAY AFTERNOON...A QLCS WITH A HISTORY OF SCATTERED WIND
DAMAGE WAS CROSSING THE SAVANNAH RIVER AND WAS HEADING E/NE TOWARD
SC LOCATIONS ALONG/E OF I-95...PERHAPS AS FAR NORTH AS THE
CHARLESTON TRI-COUNTY REGION...AND ADJACENT COASTAL WATERS. ALONG
THE OUTFLOW TRAILING THIS THUNDERSTORM COMPLEX...ADDITIONAL
MULTICELL THUNDERSTORMS HAD DEVELOPED AND WERE ADVANCING TOWARD SE
GA LOCALES ALONG THE ALTAMAHA RIVER.

MEANWHILE...THUNDERSTORMS ASSOCIATED WITH THE MIDLANDS SHORTWAVE
HAD THUS FAR REMAINED NORTH OF THE REGION...BUT SCATTERED
THUNDERSTORMS COULD EXPAND SOUTH INTO SC COUNTIES THIS AFTERNOON.

ADJUSTED AFTERNOON POP FORECASTS TO ACCOUNT FOR THESE TRENDS.
ALSO...COMPLETED SIGNIFICANT TEMPERATURE ADJUSTMENTS TO ACCOUNT
FOR IMPACTS OF CLOUDS/THUNDERSTORMS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
TONIGHT...TAIL END OF LEAD SHORTWAVE AND A SECONDARY/FOLLOWING
WILL EXTEND THE DURATION OF SLIGHT CHANCE/CHANCE POPS AT LEAST .
SHORTWAVE UPPER DISTURBANCE WILL FOLLOW THE LEAD SHORT WAVE AND
MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET MAINLY
ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD QUIET
DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY
AROUND SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS ARE
HIGH...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS THIS AFTERNOON.
OUTSIDE THUNDERSTORMS...SW WINDS 15-20 KT AND SEAS 2-3 FT WITHIN
NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. OUTSIDE THUNDERSTORMS...
ELEVATED W/SW WINDS AND SIMILAR SEAS WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 191804
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
204 PM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY TUESDAY AFTERNOON...A QLCS WITH A HISTORY OF SCATTERED WIND
DAMAGE WAS CROSSING THE SAVANNAH RIVER AND WAS HEADING E/NE TOWARD
SC LOCATIONS ALONG/E OF I-95...PERHAPS AS FAR NORTH AS THE
CHARLESTON TRI-COUNTY REGION...AND ADJACENT COASTAL WATERS. ALONG
THE OUTFLOW TRAILING THIS THUNDERSTORM COMPLEX...ADDITIONAL
MULTICELL THUNDERSTORMS HAD DEVELOPED AND WERE ADVANCING TOWARD SE
GA LOCALES ALONG THE ALTAMAHA RIVER.

MEANWHILE...THUNDERSTORMS ASSOCIATED WITH THE MIDLANDS SHORTWAVE
HAD THUS FAR REMAINED NORTH OF THE REGION...BUT SCATTERED
THUNDERSTORMS COULD EXPAND SOUTH INTO SC COUNTIES THIS AFTERNOON.

ADJUSTED AFTERNOON POP FORECASTS TO ACCOUNT FOR THESE TRENDS.
ALSO...COMPLETED SIGNIFICANT TEMPERATURE ADJUSTMENTS TO ACCOUNT
FOR IMPACTS OF CLOUDS/THUNDERSTORMS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
TONIGHT...TAIL END OF LEAD SHORTWAVE AND A SECONDARY/FOLLOWING
WILL EXTEND THE DURATION OF SLIGHT CHANCE/CHANCE POPS AT LEAST .
SHORTWAVE UPPER DISTURBANCE WILL FOLLOW THE LEAD SHORT WAVE AND
MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET MAINLY
ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD QUIET
DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY
AROUND SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS ARE
HIGH...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
THUNDERSTORMS WILL GREATLY ALTER LOCAL WINDS THIS AFTERNOON.
OUTSIDE THUNDERSTORMS...SW WINDS 15-20 KT AND SEAS 2-3 FT WITHIN
NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. OUTSIDE THUNDERSTORMS...
ELEVATED W/SW WINDS AND SIMILAR SEAS WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KFFC 191730
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
130 PM EDT TUE AUG 19 2014



.PREV DISCUSSION... /ISSUED 1002 AM EDT TUE AUG 19 2014/

UPDATE...
MORNING ANALYSIS SHOWS A SHORTWAVE AND ASSOCIATED SHOWERS MOVING
THROUGH EASTERN AL AND WESTERN GA. UPDATES WERE PRIMARILY MADE TO
POP TRENDS AND TIMING WITH CURRENT ACTIVITY AS WELL AS POSSIBLE
DEVELOPMENT THIS AFTERNOON. SOME CHANGES WERE ALSO MADE TO SKY
COVER THROUGH THE PERIOD.

PREV DISCUSSION... /ISSUED 710 AM EDT TUE AUG 19 2014/

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/

SHORT TERM /TODAY THROUGH WEDNESDAY/...
SHORT WAVES CONTINUE TO PLAY THE MAIN ROLE IN THE FORECAST TODAY.
A STRONG SHORT WAVE MOVING ACROSS N GA THIS MORNING PRODUCING SOME
SHOWERS OVER THE NORTHERN COUNTIES WITH ANOTHER SHORT WAVE EXPECTED FOR
THE AFTERNOON. THIS SHOULD ALLOW FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS WITH MOST THUNDERSTORMS IN THE AFTERNOON AND THE
MOST LIKELY AREA TO BE CENTRAL GA WITH THE AFTERNOON SHORT WAVE.

INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STRONG STORMS AND YOU CAN
NOT RULE OUT ISOLATED SEVERE STORMS...ESPECIALLY FOR CENTRAL GA.

SOME SHOWER AND STORM ACTIVITY WILL GO INTO THE EVENING BEFORE
DIMINISHING...ESPECIALLY OVER CENTRAL GA.

ANOTHER LESS IMPRESSIVE SHORT WAVE APPROACHES N GA LATE TONIGHT AND
COULD AFFECT THE REST OF THE AREA SOME TIME DURING THE DAY
WEDNESDAY. A SURFACE TROUGH WILL HELP TO ENHANCE SHOWER AND STORM
ACTIVITY OVER THE SE COUNTIES DURING THE AFTERNOON.

FORECAST HIGH TEMPERATURES RUNNING NEAR NORMAL TODAY AND 3-6 DEGREES
ABOVE NORMAL FOR WEDNESDAY. FORECAST LOW TEMPERATURES RUNNING NEAR
NORMAL TONIGHT.

OVERALL CONFIDENCE IS MEDIUM.

BDL

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST WEST OF
THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER MISSISSIPPI
VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL ABOVE NORMAL
AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE RIDGE
CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE PULLING
POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT CHANCES WILL
BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-EAST GRADIENT
AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO TURN EASTERLY BY
LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF THE EDGE OFF OF THE
HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

.AVIATION...
18Z UPDATE...
A FEW SCATTERED SHOWERS HAVE DEVELOPED IN PARTS OF NORTHWEST
GEORGIA THIS AFTERNOON. EXPECT ISOLATED ACTIVITY TO CONTINUE ACROSS THIS
AREA PRIOR TO SUNSET...SO HAVE INCLUDED VCSH AT METRO TAF SITES TO
ACCOUNT FOR THESE. SOME MVFR FOG IS POSSIBLE AT TAF SITES
OVERNIGHT. OTHERWISE...THE REST OF THE PERIOD LOOKS QUIET.


//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE CONVECTIVE ACTIVITY. HIGH CONFIDENCE ON ALL
OTHER ELEMENTS.

RW

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          90  70  95  73 /  60  20  30  20
ATLANTA         87  72  91  75 /  40  20  30  20
BLAIRSVILLE     83  66  87  68 /  30  20  30  20
CARTERSVILLE    87  69  92  70 /  40  20  30  20
COLUMBUS        90  73  94  76 /  50  20  30  20
GAINESVILLE     86  71  90  74 /  60  20  30  20
MACON           93  70  94  74 /  40  20  30  20
ROME            87  70  93  71 /  40  20  30  20
PEACHTREE CITY  88  68  92  71 /  50  20  30  20
VIDALIA         95  74  97  76 /  60  30  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...RW
AVIATION...RW






000
FXUS62 KFFC 191730
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
130 PM EDT TUE AUG 19 2014



.PREV DISCUSSION... /ISSUED 1002 AM EDT TUE AUG 19 2014/

UPDATE...
MORNING ANALYSIS SHOWS A SHORTWAVE AND ASSOCIATED SHOWERS MOVING
THROUGH EASTERN AL AND WESTERN GA. UPDATES WERE PRIMARILY MADE TO
POP TRENDS AND TIMING WITH CURRENT ACTIVITY AS WELL AS POSSIBLE
DEVELOPMENT THIS AFTERNOON. SOME CHANGES WERE ALSO MADE TO SKY
COVER THROUGH THE PERIOD.

PREV DISCUSSION... /ISSUED 710 AM EDT TUE AUG 19 2014/

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/

SHORT TERM /TODAY THROUGH WEDNESDAY/...
SHORT WAVES CONTINUE TO PLAY THE MAIN ROLE IN THE FORECAST TODAY.
A STRONG SHORT WAVE MOVING ACROSS N GA THIS MORNING PRODUCING SOME
SHOWERS OVER THE NORTHERN COUNTIES WITH ANOTHER SHORT WAVE EXPECTED FOR
THE AFTERNOON. THIS SHOULD ALLOW FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS WITH MOST THUNDERSTORMS IN THE AFTERNOON AND THE
MOST LIKELY AREA TO BE CENTRAL GA WITH THE AFTERNOON SHORT WAVE.

INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STRONG STORMS AND YOU CAN
NOT RULE OUT ISOLATED SEVERE STORMS...ESPECIALLY FOR CENTRAL GA.

SOME SHOWER AND STORM ACTIVITY WILL GO INTO THE EVENING BEFORE
DIMINISHING...ESPECIALLY OVER CENTRAL GA.

ANOTHER LESS IMPRESSIVE SHORT WAVE APPROACHES N GA LATE TONIGHT AND
COULD AFFECT THE REST OF THE AREA SOME TIME DURING THE DAY
WEDNESDAY. A SURFACE TROUGH WILL HELP TO ENHANCE SHOWER AND STORM
ACTIVITY OVER THE SE COUNTIES DURING THE AFTERNOON.

FORECAST HIGH TEMPERATURES RUNNING NEAR NORMAL TODAY AND 3-6 DEGREES
ABOVE NORMAL FOR WEDNESDAY. FORECAST LOW TEMPERATURES RUNNING NEAR
NORMAL TONIGHT.

OVERALL CONFIDENCE IS MEDIUM.

BDL

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST WEST OF
THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER MISSISSIPPI
VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL ABOVE NORMAL
AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE RIDGE
CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE PULLING
POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT CHANCES WILL
BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-EAST GRADIENT
AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO TURN EASTERLY BY
LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF THE EDGE OFF OF THE
HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

.AVIATION...
18Z UPDATE...
A FEW SCATTERED SHOWERS HAVE DEVELOPED IN PARTS OF NORTHWEST
GEORGIA THIS AFTERNOON. EXPECT ISOLATED ACTIVITY TO CONTINUE ACROSS THIS
AREA PRIOR TO SUNSET...SO HAVE INCLUDED VCSH AT METRO TAF SITES TO
ACCOUNT FOR THESE. SOME MVFR FOG IS POSSIBLE AT TAF SITES
OVERNIGHT. OTHERWISE...THE REST OF THE PERIOD LOOKS QUIET.


//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE CONVECTIVE ACTIVITY. HIGH CONFIDENCE ON ALL
OTHER ELEMENTS.

RW

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          90  70  95  73 /  60  20  30  20
ATLANTA         87  72  91  75 /  40  20  30  20
BLAIRSVILLE     83  66  87  68 /  30  20  30  20
CARTERSVILLE    87  69  92  70 /  40  20  30  20
COLUMBUS        90  73  94  76 /  50  20  30  20
GAINESVILLE     86  71  90  74 /  60  20  30  20
MACON           93  70  94  74 /  40  20  30  20
ROME            87  70  93  71 /  40  20  30  20
PEACHTREE CITY  88  68  92  71 /  50  20  30  20
VIDALIA         95  74  97  76 /  60  30  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...RW
AVIATION...RW





000
FXUS62 KCAE 191641
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1241 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPPER LEVEL DISTURBANCE AND ASSOCIATED CLOUDINESS AND LIGHT SHOWER
ACTIVITY CURRENTLY MOVING EAST ACROSS THE CENTRAL FA. BETTER HEATING
TO THE EAST ALONG WITH PVA EXPECTED TO PROMOTE SCATTERED SHOWERS AND
THUNDERSTORMS MAINLY E AND NE FA IN THE NEAR TERM. SECOND VORT
MAX...CURRENTLY OVER N AL...WILL SHIFT SE ACROSS CENT GA TO S SC
LATE TODAY AND THIS EVENING. LATEST HIGH RES MODELS SUGGEST SOME
CONVECTION POSSIBLE AHEAD OF THIS FEATURE WHICH COULD POSSIBLY
AFFECT THE CSRA LATE THIS AFTN. ADDITIONAL SCATTERED CONVECTION MAY
DEVELOP THIS AFTN ALONG A TROUGH ACROSS THE W CAROLINAS WHICH COULD
TRACK EAST TOWARDS OUR N FA. ALL IN ALL...THINK SLIGHT CHANCE TO
CHANCE POPS THIS AFTERNOON INTO THE EARLY EVENING WILL SUFFICE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

SCATTERED SHOWERS WERE IN THE FORECAST AREA EARLY AT MIDDAY ASSOCIATED
WITH A MID-LEVEL SHORTWAVE TROUGH. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER THIS AFTERNOON. THE HIGH RESOLUTION MODELS
INDICATE SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN
LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT ASSOCIATED WITH THE
SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 191641
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1241 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPPER LEVEL DISTURBANCE AND ASSOCIATED CLOUDINESS AND LIGHT SHOWER
ACTIVITY CURRENTLY MOVING EAST ACROSS THE CENTRAL FA. BETTER HEATING
TO THE EAST ALONG WITH PVA EXPECTED TO PROMOTE SCATTERED SHOWERS AND
THUNDERSTORMS MAINLY E AND NE FA IN THE NEAR TERM. SECOND VORT
MAX...CURRENTLY OVER N AL...WILL SHIFT SE ACROSS CENT GA TO S SC
LATE TODAY AND THIS EVENING. LATEST HIGH RES MODELS SUGGEST SOME
CONVECTION POSSIBLE AHEAD OF THIS FEATURE WHICH COULD POSSIBLY
AFFECT THE CSRA LATE THIS AFTN. ADDITIONAL SCATTERED CONVECTION MAY
DEVELOP THIS AFTN ALONG A TROUGH ACROSS THE W CAROLINAS WHICH COULD
TRACK EAST TOWARDS OUR N FA. ALL IN ALL...THINK SLIGHT CHANCE TO
CHANCE POPS THIS AFTERNOON INTO THE EARLY EVENING WILL SUFFICE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

SCATTERED SHOWERS WERE IN THE FORECAST AREA EARLY AT MIDDAY ASSOCIATED
WITH A MID-LEVEL SHORTWAVE TROUGH. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER THIS AFTERNOON. THE HIGH RESOLUTION MODELS
INDICATE SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN
LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT ASSOCIATED WITH THE
SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 191641
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1241 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPPER LEVEL DISTURBANCE AND ASSOCIATED CLOUDINESS AND LIGHT SHOWER
ACTIVITY CURRENTLY MOVING EAST ACROSS THE CENTRAL FA. BETTER HEATING
TO THE EAST ALONG WITH PVA EXPECTED TO PROMOTE SCATTERED SHOWERS AND
THUNDERSTORMS MAINLY E AND NE FA IN THE NEAR TERM. SECOND VORT
MAX...CURRENTLY OVER N AL...WILL SHIFT SE ACROSS CENT GA TO S SC
LATE TODAY AND THIS EVENING. LATEST HIGH RES MODELS SUGGEST SOME
CONVECTION POSSIBLE AHEAD OF THIS FEATURE WHICH COULD POSSIBLY
AFFECT THE CSRA LATE THIS AFTN. ADDITIONAL SCATTERED CONVECTION MAY
DEVELOP THIS AFTN ALONG A TROUGH ACROSS THE W CAROLINAS WHICH COULD
TRACK EAST TOWARDS OUR N FA. ALL IN ALL...THINK SLIGHT CHANCE TO
CHANCE POPS THIS AFTERNOON INTO THE EARLY EVENING WILL SUFFICE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

SCATTERED SHOWERS WERE IN THE FORECAST AREA EARLY AT MIDDAY ASSOCIATED
WITH A MID-LEVEL SHORTWAVE TROUGH. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER THIS AFTERNOON. THE HIGH RESOLUTION MODELS
INDICATE SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN
LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT ASSOCIATED WITH THE
SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 191641
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1241 PM EDT TUE AUG 19 2014

.SYNOPSIS...
DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE WILL
INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPPER LEVEL DISTURBANCE AND ASSOCIATED CLOUDINESS AND LIGHT SHOWER
ACTIVITY CURRENTLY MOVING EAST ACROSS THE CENTRAL FA. BETTER HEATING
TO THE EAST ALONG WITH PVA EXPECTED TO PROMOTE SCATTERED SHOWERS AND
THUNDERSTORMS MAINLY E AND NE FA IN THE NEAR TERM. SECOND VORT
MAX...CURRENTLY OVER N AL...WILL SHIFT SE ACROSS CENT GA TO S SC
LATE TODAY AND THIS EVENING. LATEST HIGH RES MODELS SUGGEST SOME
CONVECTION POSSIBLE AHEAD OF THIS FEATURE WHICH COULD POSSIBLY
AFFECT THE CSRA LATE THIS AFTN. ADDITIONAL SCATTERED CONVECTION MAY
DEVELOP THIS AFTN ALONG A TROUGH ACROSS THE W CAROLINAS WHICH COULD
TRACK EAST TOWARDS OUR N FA. ALL IN ALL...THINK SLIGHT CHANCE TO
CHANCE POPS THIS AFTERNOON INTO THE EARLY EVENING WILL SUFFICE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

SCATTERED SHOWERS WERE IN THE FORECAST AREA EARLY AT MIDDAY ASSOCIATED
WITH A MID-LEVEL SHORTWAVE TROUGH. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER THIS AFTERNOON. THE HIGH RESOLUTION MODELS
INDICATE SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN
LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT ASSOCIATED WITH THE
SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCHS 191613
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1213 PM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH
PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATE TUESDAY MORNING...RAISED POPS ALONG/SOUTH OF 1-16 TO ACCOUNT
FOR MULTICELL THUNDERSTORMS ADVANCING INTO THIS AREA AND
DEVELOPING UPSTREAM.

AREA 12Z SOUNDINGS SAMPLED AN UNSEASONABLY STRONG/DEEP WESTERLY
FLOW REGIME IN PLACE OVER THE REGION...WITH 925-500 MB WINDS
RANGING FROM 15-25 KT OVER SOUTHERN COUNTIES TO 25-30 KT ACROSS
THE NORTH. LATE-MORNING MESOANALYSIS REVEALED A N-S STABILITY
GRADIENT OVER THE REGION WITH MLCAPES 2000-2500 J/KG AND DCAPES
600-800 J/KG ALONG/SOUTH OF I-16. THUNDERSTORMS MOVING INTO THIS
AREA WERE SUPPORTED BY A BAND OF 0-1 KM BULK SHEAR 20-25 KT AND
WERE PUSHING QUICKLY EAST 30-35 KT. THIS REGIME WILL SUPPORT AN
ISOLATED DAMAGING WIND THREAT AS ADDITIONAL MULTICELL
THUNDERSTORMS IMPACT SOUTHERN COUNTIES WITH ELEVATED POPS THIS
AFTERNOON.

FARTHER NORTH...A WELL-DEFINED SHORTWAVE ADVANCING THROUGH THE SC
MIDLANDS WILL PUSH QUICKLY TOWARD THE UPPER SC COAST THIS
AFTERNOON. THIS FEATURE SHOULD SUPPORT SCATTERED MULTICELL
THUNDERSTORMS WHICH WILL LIKELY PUSH INTO AREAS NORTH OF I-16 THIS
AFTERNOON. EVEN IN THIS AREA...SCATTERED/FAST-MOVING MULTICELL
THUNDERSTORMS AND MLCAPES AS HIGH AS 1500-2000 J/KG WILL SUPPORT
AN ISOLATED THREAT FOR BRIEF/DAMAGING WIND GUSTS.

OUTSIDE THUNDERSTORMS...EXPECT ANOTHER HOT AFTERNOON WITH TEMPS
WARMING TO MID 90S AT MANY LOCATIONS. OFFSHORE FLOW WILL PUSH 90S
TO THE BEACHES BEFORE THE SEA BREEZE DEVELOP MID TO LATE
AFTERNOON. AS ALWAYS...THUNDERSTORMS WILL GREATLY ALTER LOCAL
TEMPS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
THIS EVENING...A SECONDARY UPPER DISTURBANCE WILL FOLLOW THE LEAD
SHORT WAVE AND MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET
MAINLY ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD
QUIET DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY
AROUND SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS ARE
HIGH...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
OFFSHORE WINDS 15-20 KT WILL TURN TOWARD THE SW AS THE SEA BREEZE
CIRCULATION DEVELOPS THIS AFTERNOON. SEAS WILL RANGE FROM 2-4 FT
WITHIN NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. ELEVATED W/SW WINDS
WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...






000
FXUS62 KCAE 191559
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1159 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND STRONG HEATING WILL SUPPORT SCATTERED
THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE THUNDERSTORM
CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE
WILL INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...A WELL-DEFINED MID-LEVEL SHORTWAVE TROUGH WAS
SUPPORTING CLOUDINESS OVER MUCH OF THE FORECAST AREA AT MIDDAY. LIFT
ASSOCIATED WITH THIS FEATURE SHOULD BE MAINLY EAST OF THE FORECAST
AREA BY THE MIDDLE OF THE AFTERNOON. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER TODAY. THE HIGH RESOLUTION MODELS INDICATE
SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN LIMITED
BECAUSE OF DIMINISHED UPPER-LEVEL SUPPORT. ALSO...CONVERGENCE
INTO THE SURFACE FEATURE SHOULD REMAIN WEAK AND FORECAST SOUNDINGS
SHOW WESTERLY FLOW THROUGH A DEEP LAYER WHICH SHOULD HELP KEEP
MOISTURE SOMEWHAT SHALLOW. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR
WITH 5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND
STEEP LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS
WITH ANY THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED
THE GFS LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND
GUST FORECAST. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF THE
WESTERLY FLOW.

TONIGHT...THE MODELS MAINTAIN SURFACE TROUGHING. HOWEVER...BELIEVE
THE THUNDERSTORM CHANCE IS LOW BECAUSE OF SHALLOW MOISTURE IN THE
WAKE OF THE MID-LEVEL SHORTWAVE TROUGH AND NOCTURNAL COOLING. THE
NAM AND GFS MOS HAVE POPS 20 TO 30 PERCENT...MAINLY IN THE EVENING
CLOSER TO THE TIME OF HEATING. THE TEMPERATURE GUIDANCE WAS CLOSE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

SCATTERED SHOWERS WERE IN THE FORECAST AREA EARLY AT MIDDAY ASSOCIATED
WITH A MID-LEVEL SHORTWAVE TROUGH. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER THIS AFTERNOON. THE HIGH RESOLUTION MODELS
INDICATE SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN
LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT ASSOCIATED WITH THE
SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$








000
FXUS62 KCAE 191559
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1159 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND STRONG HEATING WILL SUPPORT SCATTERED
THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE THUNDERSTORM
CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE
WILL INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...A WELL-DEFINED MID-LEVEL SHORTWAVE TROUGH WAS
SUPPORTING CLOUDINESS OVER MUCH OF THE FORECAST AREA AT MIDDAY. LIFT
ASSOCIATED WITH THIS FEATURE SHOULD BE MAINLY EAST OF THE FORECAST
AREA BY THE MIDDLE OF THE AFTERNOON. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER TODAY. THE HIGH RESOLUTION MODELS INDICATE
SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN LIMITED
BECAUSE OF DIMINISHED UPPER-LEVEL SUPPORT. ALSO...CONVERGENCE
INTO THE SURFACE FEATURE SHOULD REMAIN WEAK AND FORECAST SOUNDINGS
SHOW WESTERLY FLOW THROUGH A DEEP LAYER WHICH SHOULD HELP KEEP
MOISTURE SOMEWHAT SHALLOW. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR
WITH 5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND
STEEP LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS
WITH ANY THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED
THE GFS LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND
GUST FORECAST. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF THE
WESTERLY FLOW.

TONIGHT...THE MODELS MAINTAIN SURFACE TROUGHING. HOWEVER...BELIEVE
THE THUNDERSTORM CHANCE IS LOW BECAUSE OF SHALLOW MOISTURE IN THE
WAKE OF THE MID-LEVEL SHORTWAVE TROUGH AND NOCTURNAL COOLING. THE
NAM AND GFS MOS HAVE POPS 20 TO 30 PERCENT...MAINLY IN THE EVENING
CLOSER TO THE TIME OF HEATING. THE TEMPERATURE GUIDANCE WAS CLOSE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

SCATTERED SHOWERS WERE IN THE FORECAST AREA EARLY AT MIDDAY ASSOCIATED
WITH A MID-LEVEL SHORTWAVE TROUGH. THE TROUGH PLUS HEATING AND
CONVERGENCE INTO THE LEE-SIDE SURFACE TROUGH SHOULD HELP SUPPORT
THUNDERSTORMS LATER THIS AFTERNOON. THE HIGH RESOLUTION MODELS
INDICATE SCATTERED COVERAGE. THE COVERAGE WILL PROBABLY REMAIN
LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT ASSOCIATED WITH THE
SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCHS 191425
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1025 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TUESDAY MORNING...AREA 12Z SOUNDINGS CONFIRMED AN UNSEASONABLY
STRONG/DEEP WESTERLY FLOW REGIME IN PLACE OVER THE REGION...WITH
925-500 MB WINDS RANGING FROM 15-25 KT OVER SOUTHERN COUNTIES TO
25-30 KT ACROSS THE NORTH. MID-MORNING MESOANALYSIS REVEALED A
N-S STABILITY GRADIENT OVER THE REGION WITH MLCAPES AROUND 1500
J/KG AND DCAPES APPROACHING 1000 J/KG ALONG/SOUTH OF I-16.
THUNDERSTORMS HAD ALREADY DEVELOPED UPSTREAM ALONG THIS GRADIENT/
ALONG OUTFLOW CREATED BY A CLUSTER OF CONVECTION WHICH ADVANCED
INTO WESTERN GA. THESE MULTICELL THUNDERSTORMS HAD DEVELOPED
WITHIN A BAND OF 0-1 KM BULK SHEAR 20-25 KT AND WERE PUSHING
QUICKLY EAST AT 35 MPH. THESE THUNDERSTORMS WILL ADVANCE INTO
AREAS SOUTH OF I-16 LATER THIS MORNING AND WILL LIKELY SUPPORT NEW
CONVECTION WITHIN EXPANDING CUMULUS FIELD OVER SE GA. ADJUSTED
POPS TO ACCOUNT FOR AN EARLIER ONSET OF AT LEAST SCATTERED
THUNDERSTORMS ALONG/SOUTH OF I-16...AND THIS REGIME SHOULD PERSIST
THROUGH THIS AFTERNOON.

FARTHER NORTH...ONGOING FORECASTS REMAIN ON TRACK AND DID NOT REQUIRE
SIGNIFICANT ADJUSTMENTS. A WELL-DEFINED SHORTWAVE ADVANCING INTO
THE SC MIDLANDS WILL PUSH QUICKLY TOWARD THE UPPER SC COAST THIS
AFTERNOON. THIS FEATURE SHOULD SUPPORT SCATTERED MULTICELL
THUNDERSTORMS WHICH WILL LIKELY PUSH INTO AREAS NORTH OF I-16 THIS
AFTERNOON.

ELEVATED LOW-LEVEL SHEAR/UNUSUALLY STRONG TROPOSPHERIC WINDS
WILL SUPPORT MULTICELL THUNDERSTORMS WHICH WILL MOVE QUICKLY
EASTWARD AT GREATER THAN 30 MPH. MODIFIED SOUNDINGS ONLY YIELD
MLCAPES IN THE 1500-2500 J/KG RANGE...HIGHEST SOUTH BUT OVERALL A
BIT MORE STABLE THAN MONDAY...AS STRONGER INSTABILITY WILL REMAIN
OFFSHORE AS THE SEA BREEZE WILL REMAIN PINNED AT THE COAST THIS
AFTERNOON. HOWEVER...ELEVATED WINDS AND INCREASING DOWNDRAFT CAPES
COULD SUPPORT A ISOLATED THREAT FOR DAMAGING WIND GUSTS.
ALONG/SOUTH OF I-16...STRONGER INSTABILITY AND ELEVATED DOWNDRAFT
CAPES COULD SUPPORT A SOMEWHAT GREATER THREAT FOR DAMAGING WINDS.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN
SOME AREAS BY MIDDAY AND REACHING AT LEAST THE MID 90S. OFFSHORE
FLOW WILL PUSH 90S TO THE BEACHES BEFORE THE SEA BREEZE DEVELOP
MID TO LATE AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
THIS EVENING...A SECONDARY UPPER DISTURBANCE WILL FOLLOW THE LEAD
SHORT WAVE AND MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET
MAINLY ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD
QUIET DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
DEVELOPING CUMULUS COULD SUPPORT BRIEF MVFR CEILINGS AT KSAV
THROUGH MIDDAY.

SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY AROUND
SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS IN
INCREASING...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
OFFSHORE WINDS 15-20 KT WILL TURN TOWARD THE SW AS THE SEA BREEZE
CIRCULATION DEVELOPS THIS AFTERNOON. SEAS WILL RANGE FROM 2-4 FT
WITHIN NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. ELEVATED W/SW WINDS
WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 191425
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1025 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TUESDAY MORNING...AREA 12Z SOUNDINGS CONFIRMED AN UNSEASONABLY
STRONG/DEEP WESTERLY FLOW REGIME IN PLACE OVER THE REGION...WITH
925-500 MB WINDS RANGING FROM 15-25 KT OVER SOUTHERN COUNTIES TO
25-30 KT ACROSS THE NORTH. MID-MORNING MESOANALYSIS REVEALED A
N-S STABILITY GRADIENT OVER THE REGION WITH MLCAPES AROUND 1500
J/KG AND DCAPES APPROACHING 1000 J/KG ALONG/SOUTH OF I-16.
THUNDERSTORMS HAD ALREADY DEVELOPED UPSTREAM ALONG THIS GRADIENT/
ALONG OUTFLOW CREATED BY A CLUSTER OF CONVECTION WHICH ADVANCED
INTO WESTERN GA. THESE MULTICELL THUNDERSTORMS HAD DEVELOPED
WITHIN A BAND OF 0-1 KM BULK SHEAR 20-25 KT AND WERE PUSHING
QUICKLY EAST AT 35 MPH. THESE THUNDERSTORMS WILL ADVANCE INTO
AREAS SOUTH OF I-16 LATER THIS MORNING AND WILL LIKELY SUPPORT NEW
CONVECTION WITHIN EXPANDING CUMULUS FIELD OVER SE GA. ADJUSTED
POPS TO ACCOUNT FOR AN EARLIER ONSET OF AT LEAST SCATTERED
THUNDERSTORMS ALONG/SOUTH OF I-16...AND THIS REGIME SHOULD PERSIST
THROUGH THIS AFTERNOON.

FARTHER NORTH...ONGOING FORECASTS REMAIN ON TRACK AND DID NOT REQUIRE
SIGNIFICANT ADJUSTMENTS. A WELL-DEFINED SHORTWAVE ADVANCING INTO
THE SC MIDLANDS WILL PUSH QUICKLY TOWARD THE UPPER SC COAST THIS
AFTERNOON. THIS FEATURE SHOULD SUPPORT SCATTERED MULTICELL
THUNDERSTORMS WHICH WILL LIKELY PUSH INTO AREAS NORTH OF I-16 THIS
AFTERNOON.

ELEVATED LOW-LEVEL SHEAR/UNUSUALLY STRONG TROPOSPHERIC WINDS
WILL SUPPORT MULTICELL THUNDERSTORMS WHICH WILL MOVE QUICKLY
EASTWARD AT GREATER THAN 30 MPH. MODIFIED SOUNDINGS ONLY YIELD
MLCAPES IN THE 1500-2500 J/KG RANGE...HIGHEST SOUTH BUT OVERALL A
BIT MORE STABLE THAN MONDAY...AS STRONGER INSTABILITY WILL REMAIN
OFFSHORE AS THE SEA BREEZE WILL REMAIN PINNED AT THE COAST THIS
AFTERNOON. HOWEVER...ELEVATED WINDS AND INCREASING DOWNDRAFT CAPES
COULD SUPPORT A ISOLATED THREAT FOR DAMAGING WIND GUSTS.
ALONG/SOUTH OF I-16...STRONGER INSTABILITY AND ELEVATED DOWNDRAFT
CAPES COULD SUPPORT A SOMEWHAT GREATER THREAT FOR DAMAGING WINDS.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN
SOME AREAS BY MIDDAY AND REACHING AT LEAST THE MID 90S. OFFSHORE
FLOW WILL PUSH 90S TO THE BEACHES BEFORE THE SEA BREEZE DEVELOP
MID TO LATE AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
THIS EVENING...A SECONDARY UPPER DISTURBANCE WILL FOLLOW THE LEAD
SHORT WAVE AND MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET
MAINLY ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD
QUIET DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
DEVELOPING CUMULUS COULD SUPPORT BRIEF MVFR CEILINGS AT KSAV
THROUGH MIDDAY.

SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY AROUND
SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS IN
INCREASING...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
OFFSHORE WINDS 15-20 KT WILL TURN TOWARD THE SW AS THE SEA BREEZE
CIRCULATION DEVELOPS THIS AFTERNOON. SEAS WILL RANGE FROM 2-4 FT
WITHIN NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. ELEVATED W/SW WINDS
WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 191425
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1025 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TUESDAY MORNING...AREA 12Z SOUNDINGS CONFIRMED AN UNSEASONABLY
STRONG/DEEP WESTERLY FLOW REGIME IN PLACE OVER THE REGION...WITH
925-500 MB WINDS RANGING FROM 15-25 KT OVER SOUTHERN COUNTIES TO
25-30 KT ACROSS THE NORTH. MID-MORNING MESOANALYSIS REVEALED A
N-S STABILITY GRADIENT OVER THE REGION WITH MLCAPES AROUND 1500
J/KG AND DCAPES APPROACHING 1000 J/KG ALONG/SOUTH OF I-16.
THUNDERSTORMS HAD ALREADY DEVELOPED UPSTREAM ALONG THIS GRADIENT/
ALONG OUTFLOW CREATED BY A CLUSTER OF CONVECTION WHICH ADVANCED
INTO WESTERN GA. THESE MULTICELL THUNDERSTORMS HAD DEVELOPED
WITHIN A BAND OF 0-1 KM BULK SHEAR 20-25 KT AND WERE PUSHING
QUICKLY EAST AT 35 MPH. THESE THUNDERSTORMS WILL ADVANCE INTO
AREAS SOUTH OF I-16 LATER THIS MORNING AND WILL LIKELY SUPPORT NEW
CONVECTION WITHIN EXPANDING CUMULUS FIELD OVER SE GA. ADJUSTED
POPS TO ACCOUNT FOR AN EARLIER ONSET OF AT LEAST SCATTERED
THUNDERSTORMS ALONG/SOUTH OF I-16...AND THIS REGIME SHOULD PERSIST
THROUGH THIS AFTERNOON.

FARTHER NORTH...ONGOING FORECASTS REMAIN ON TRACK AND DID NOT REQUIRE
SIGNIFICANT ADJUSTMENTS. A WELL-DEFINED SHORTWAVE ADVANCING INTO
THE SC MIDLANDS WILL PUSH QUICKLY TOWARD THE UPPER SC COAST THIS
AFTERNOON. THIS FEATURE SHOULD SUPPORT SCATTERED MULTICELL
THUNDERSTORMS WHICH WILL LIKELY PUSH INTO AREAS NORTH OF I-16 THIS
AFTERNOON.

ELEVATED LOW-LEVEL SHEAR/UNUSUALLY STRONG TROPOSPHERIC WINDS
WILL SUPPORT MULTICELL THUNDERSTORMS WHICH WILL MOVE QUICKLY
EASTWARD AT GREATER THAN 30 MPH. MODIFIED SOUNDINGS ONLY YIELD
MLCAPES IN THE 1500-2500 J/KG RANGE...HIGHEST SOUTH BUT OVERALL A
BIT MORE STABLE THAN MONDAY...AS STRONGER INSTABILITY WILL REMAIN
OFFSHORE AS THE SEA BREEZE WILL REMAIN PINNED AT THE COAST THIS
AFTERNOON. HOWEVER...ELEVATED WINDS AND INCREASING DOWNDRAFT CAPES
COULD SUPPORT A ISOLATED THREAT FOR DAMAGING WIND GUSTS.
ALONG/SOUTH OF I-16...STRONGER INSTABILITY AND ELEVATED DOWNDRAFT
CAPES COULD SUPPORT A SOMEWHAT GREATER THREAT FOR DAMAGING WINDS.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN
SOME AREAS BY MIDDAY AND REACHING AT LEAST THE MID 90S. OFFSHORE
FLOW WILL PUSH 90S TO THE BEACHES BEFORE THE SEA BREEZE DEVELOP
MID TO LATE AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
THIS EVENING...A SECONDARY UPPER DISTURBANCE WILL FOLLOW THE LEAD
SHORT WAVE AND MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET
MAINLY ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD
QUIET DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
DEVELOPING CUMULUS COULD SUPPORT BRIEF MVFR CEILINGS AT KSAV
THROUGH MIDDAY.

SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY AROUND
SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS IN
INCREASING...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
OFFSHORE WINDS 15-20 KT WILL TURN TOWARD THE SW AS THE SEA BREEZE
CIRCULATION DEVELOPS THIS AFTERNOON. SEAS WILL RANGE FROM 2-4 FT
WITHIN NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. ELEVATED W/SW WINDS
WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 191425
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1025 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TUESDAY MORNING...AREA 12Z SOUNDINGS CONFIRMED AN UNSEASONABLY
STRONG/DEEP WESTERLY FLOW REGIME IN PLACE OVER THE REGION...WITH
925-500 MB WINDS RANGING FROM 15-25 KT OVER SOUTHERN COUNTIES TO
25-30 KT ACROSS THE NORTH. MID-MORNING MESOANALYSIS REVEALED A
N-S STABILITY GRADIENT OVER THE REGION WITH MLCAPES AROUND 1500
J/KG AND DCAPES APPROACHING 1000 J/KG ALONG/SOUTH OF I-16.
THUNDERSTORMS HAD ALREADY DEVELOPED UPSTREAM ALONG THIS GRADIENT/
ALONG OUTFLOW CREATED BY A CLUSTER OF CONVECTION WHICH ADVANCED
INTO WESTERN GA. THESE MULTICELL THUNDERSTORMS HAD DEVELOPED
WITHIN A BAND OF 0-1 KM BULK SHEAR 20-25 KT AND WERE PUSHING
QUICKLY EAST AT 35 MPH. THESE THUNDERSTORMS WILL ADVANCE INTO
AREAS SOUTH OF I-16 LATER THIS MORNING AND WILL LIKELY SUPPORT NEW
CONVECTION WITHIN EXPANDING CUMULUS FIELD OVER SE GA. ADJUSTED
POPS TO ACCOUNT FOR AN EARLIER ONSET OF AT LEAST SCATTERED
THUNDERSTORMS ALONG/SOUTH OF I-16...AND THIS REGIME SHOULD PERSIST
THROUGH THIS AFTERNOON.

FARTHER NORTH...ONGOING FORECASTS REMAIN ON TRACK AND DID NOT REQUIRE
SIGNIFICANT ADJUSTMENTS. A WELL-DEFINED SHORTWAVE ADVANCING INTO
THE SC MIDLANDS WILL PUSH QUICKLY TOWARD THE UPPER SC COAST THIS
AFTERNOON. THIS FEATURE SHOULD SUPPORT SCATTERED MULTICELL
THUNDERSTORMS WHICH WILL LIKELY PUSH INTO AREAS NORTH OF I-16 THIS
AFTERNOON.

ELEVATED LOW-LEVEL SHEAR/UNUSUALLY STRONG TROPOSPHERIC WINDS
WILL SUPPORT MULTICELL THUNDERSTORMS WHICH WILL MOVE QUICKLY
EASTWARD AT GREATER THAN 30 MPH. MODIFIED SOUNDINGS ONLY YIELD
MLCAPES IN THE 1500-2500 J/KG RANGE...HIGHEST SOUTH BUT OVERALL A
BIT MORE STABLE THAN MONDAY...AS STRONGER INSTABILITY WILL REMAIN
OFFSHORE AS THE SEA BREEZE WILL REMAIN PINNED AT THE COAST THIS
AFTERNOON. HOWEVER...ELEVATED WINDS AND INCREASING DOWNDRAFT CAPES
COULD SUPPORT A ISOLATED THREAT FOR DAMAGING WIND GUSTS.
ALONG/SOUTH OF I-16...STRONGER INSTABILITY AND ELEVATED DOWNDRAFT
CAPES COULD SUPPORT A SOMEWHAT GREATER THREAT FOR DAMAGING WINDS.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN
SOME AREAS BY MIDDAY AND REACHING AT LEAST THE MID 90S. OFFSHORE
FLOW WILL PUSH 90S TO THE BEACHES BEFORE THE SEA BREEZE DEVELOP
MID TO LATE AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
THIS EVENING...A SECONDARY UPPER DISTURBANCE WILL FOLLOW THE LEAD
SHORT WAVE AND MAY KEEP SOME CONVECTION GOING A WHILE AFTER SUNSET
MAINLY ALONG/EAST OF I-95. BY LATE EVENING... CONDITIONS SHOULD
QUIET DOWN WITH A STEADY LOW LEVEL PRES GRADIENT OVER THE REGION
SUGGESTING FOG WILL NOT BE AN ISSUE.

A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
DEVELOPING CUMULUS COULD SUPPORT BRIEF MVFR CEILINGS AT KSAV
THROUGH MIDDAY.

SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP...BY MIDDAY AROUND
SAVANNAH WHERE THE PROBABILITY FOR DIRECT IMPACTS IN
INCREASING...AND EARLY/MID AFTERNOON AT KCHS...WHERE CB/VCTS ARE
FORECAST. GUSTY/SHIFTING WINDS/FLIGHT RESTRICTIONS WILL ACCOMPANY
ANY THUNDERSTORMS. WILL AMEND TAFS AS NEEDED BASED ON NEAR TERM
CONVECTIVE TRENDS.

OUTSIDE OF THESE EPISODES...VFR THROUGH TONIGHT.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
OFFSHORE WINDS 15-20 KT WILL TURN TOWARD THE SW AS THE SEA BREEZE
CIRCULATION DEVELOPS THIS AFTERNOON. SEAS WILL RANGE FROM 2-4 FT
WITHIN NEARSHORE WATERS TO 4-5 FT BEYOND 20 NM. ELEVATED W/SW WINDS
WILL CONTINUE TONIGHT.

LAND-BASED TSTMS WILL READILY SHIFT OVER THE WATERS THIS
AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE GUSTY WINDS IN
EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES. CONVECTION OVER THE
WATERS WILL DIMINISH LATE IN THE EVENING AND OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
CLIMATE...
EQUIPMENT...






000
FXUS62 KFFC 191402
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1002 AM EDT TUE AUG 19 2014


.UPDATE...
MORNING ANALYSIS SHOWS A SHORTWAVE AND ASSOCIATED SHOWERS MOVING
THROUGH EASTERN AL AND WESTERN GA. UPDATES WERE PRIMARILY MADE TO
POP TRENDS AND TIMING WITH CURRENT ACTIVITY AS WELL AS POSSIBLE
DEVELOPMENT THIS AFTERNOON. SOME CHANGES WERE ALSO MADE TO SKY
COVER THROUGH THE PERIOD.

&&

.PREV DISCUSSION... /ISSUED 710 AM EDT TUE AUG 19 2014/

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/

SHORT TERM /TODAY THROUGH WEDNESDAY/...
SHORT WAVES CONTINUE TO PLAY THE MAIN ROLE IN THE FORECAST TODAY.
A STRONG SHORT WAVE MOVING ACROSS N GA THIS MORNING PRODUCING SOME
SHOWERS OVER THE NORTHERN COUNTIES WITH ANOTHER SHORT WAVE EXPECTED FOR
THE AFTERNOON. THIS SHOULD ALLOW FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS WITH MOST THUNDERSTORMS IN THE AFTERNOON AND THE
MOST LIKELY AREA TO BE CENTRAL GA WITH THE AFTERNOON SHORT WAVE.

INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STRONG STORMS AND YOU CAN
NOT RULE OUT ISOLATED SEVERE STORMS...ESPECIALLY FOR CENTRAL GA.

SOME SHOWER AND STORM ACTIVITY WILL GO INTO THE EVENING BEFORE
DIMINISHING...ESPECIALLY OVER CENTRAL GA.

ANOTHER LESS IMPRESSIVE SHORT WAVE APPROACHES N GA LATE TONIGHT AND
COULD AFFECT THE REST OF THE AREA SOME TIME DURING THE DAY
WEDNESDAY. A SURFACE TROUGH WILL HELP TO ENHANCE SHOWER AND STORM
ACTIVITY OVER THE SE COUNTIES DURING THE AFTERNOON.

FORECAST HIGH TEMPERATURES RUNNING NEAR NORMAL TODAY AND 3-6 DEGREES
ABOVE NORMAL FOR WEDNESDAY. FORECAST LOW TEMPERATURES RUNNING NEAR
NORMAL TONIGHT.

OVERALL CONFIDENCE IS MEDIUM.

BDL

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST WEST OF
THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER MISSISSIPPI
VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL ABOVE NORMAL
AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE RIDGE
CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE PULLING
POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT CHANCES WILL
BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-EAST GRADIENT
AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO TURN EASTERLY BY
LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF THE EDGE OFF OF THE
HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

AVIATION...
12Z UPDATE...
ANY IFR-MVFR CEILINGS EXPECTED TO IMPROVE TO VFR. SHOWER AND
THUNDERSTORM POTENTIAL THROUGHOUT THE DAY WITH TIMING AT ANY TAF
SITE UNCERTAIN. SURFACE WINDS INCREASING TO MAINLY WEST AROUND 10
KTS WITH SOME GUSTS AROUND 20 KTS.

//ATL CONFIDENCE...12Z UPDATE...
LOW CONFIDENCE ON CEILINGS AND IMPACTS OF THUNDERSTORMS.
 TEMPO 1918/1922 VRB15G30KT 3SM TSRA BKN035CBHIGH CONFIDENCE ON WINDS.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          90  70  95  73 /  60  20  20  20
ATLANTA         87  72  91  75 /  40  20  20  20
BLAIRSVILLE     83  66  87  68 /  40  20  30  20
CARTERSVILLE    87  69  92  70 /  40  20  20  20
COLUMBUS        90  73  94  76 /  60  20  20  20
GAINESVILLE     86  71  90  74 /  60  20  20  20
MACON           93  70  94  74 /  50  20  20  20
ROME            87  70  93  71 /  40  20  30  20
PEACHTREE CITY  88  68  92  71 /  50  20  20  20
VIDALIA         95  74  97  76 /  60  30  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...RW





000
FXUS62 KFFC 191402
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1002 AM EDT TUE AUG 19 2014


.UPDATE...
MORNING ANALYSIS SHOWS A SHORTWAVE AND ASSOCIATED SHOWERS MOVING
THROUGH EASTERN AL AND WESTERN GA. UPDATES WERE PRIMARILY MADE TO
POP TRENDS AND TIMING WITH CURRENT ACTIVITY AS WELL AS POSSIBLE
DEVELOPMENT THIS AFTERNOON. SOME CHANGES WERE ALSO MADE TO SKY
COVER THROUGH THE PERIOD.

&&

.PREV DISCUSSION... /ISSUED 710 AM EDT TUE AUG 19 2014/

PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/

SHORT TERM /TODAY THROUGH WEDNESDAY/...
SHORT WAVES CONTINUE TO PLAY THE MAIN ROLE IN THE FORECAST TODAY.
A STRONG SHORT WAVE MOVING ACROSS N GA THIS MORNING PRODUCING SOME
SHOWERS OVER THE NORTHERN COUNTIES WITH ANOTHER SHORT WAVE EXPECTED FOR
THE AFTERNOON. THIS SHOULD ALLOW FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS WITH MOST THUNDERSTORMS IN THE AFTERNOON AND THE
MOST LIKELY AREA TO BE CENTRAL GA WITH THE AFTERNOON SHORT WAVE.

INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STRONG STORMS AND YOU CAN
NOT RULE OUT ISOLATED SEVERE STORMS...ESPECIALLY FOR CENTRAL GA.

SOME SHOWER AND STORM ACTIVITY WILL GO INTO THE EVENING BEFORE
DIMINISHING...ESPECIALLY OVER CENTRAL GA.

ANOTHER LESS IMPRESSIVE SHORT WAVE APPROACHES N GA LATE TONIGHT AND
COULD AFFECT THE REST OF THE AREA SOME TIME DURING THE DAY
WEDNESDAY. A SURFACE TROUGH WILL HELP TO ENHANCE SHOWER AND STORM
ACTIVITY OVER THE SE COUNTIES DURING THE AFTERNOON.

FORECAST HIGH TEMPERATURES RUNNING NEAR NORMAL TODAY AND 3-6 DEGREES
ABOVE NORMAL FOR WEDNESDAY. FORECAST LOW TEMPERATURES RUNNING NEAR
NORMAL TONIGHT.

OVERALL CONFIDENCE IS MEDIUM.

BDL

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST WEST OF
THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER MISSISSIPPI
VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL ABOVE NORMAL
AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE RIDGE
CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE PULLING
POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT CHANCES WILL
BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-EAST GRADIENT
AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO TURN EASTERLY BY
LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF THE EDGE OFF OF THE
HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

AVIATION...
12Z UPDATE...
ANY IFR-MVFR CEILINGS EXPECTED TO IMPROVE TO VFR. SHOWER AND
THUNDERSTORM POTENTIAL THROUGHOUT THE DAY WITH TIMING AT ANY TAF
SITE UNCERTAIN. SURFACE WINDS INCREASING TO MAINLY WEST AROUND 10
KTS WITH SOME GUSTS AROUND 20 KTS.

//ATL CONFIDENCE...12Z UPDATE...
LOW CONFIDENCE ON CEILINGS AND IMPACTS OF THUNDERSTORMS.
 TEMPO 1918/1922 VRB15G30KT 3SM TSRA BKN035CBHIGH CONFIDENCE ON WINDS.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          90  70  95  73 /  60  20  20  20
ATLANTA         87  72  91  75 /  40  20  20  20
BLAIRSVILLE     83  66  87  68 /  40  20  30  20
CARTERSVILLE    87  69  92  70 /  40  20  20  20
COLUMBUS        90  73  94  76 /  60  20  20  20
GAINESVILLE     86  71  90  74 /  60  20  20  20
MACON           93  70  94  74 /  50  20  20  20
ROME            87  70  93  71 /  40  20  30  20
PEACHTREE CITY  88  68  92  71 /  50  20  20  20
VIDALIA         95  74  97  76 /  60  30  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...RW






000
FXUS62 KCAE 191340
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
940 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND STRONG HEATING WILL SUPPORT SCATTERED
THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE THUNDERSTORM
CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE
WILL INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
TODAY...SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. THE
TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW.
SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH 5000-FOOT WINDS NEAR
30 KNOTS MAINLY IN THE SOUTH PART AND STEEP LOW-LEVEL LAPSE RATES
MAY HELP SUPPORT STRONG WIND GUSTS WITH ANY THUNDERSTORMS. STRONG
MIXING WILL BRING GUSTY WINDS. USED THE GFS LAMP AND NAM BUFKIT
MOMENTUM-TRANSFER TOOL FOR THE WIND GUST FORECAST. USED THE
WARMER TEMPERATURE GUIDANCE BECAUSE OF THE WESTERLY FLOW.

TONIGHT...THE MODELS MAINTAIN SURFACE TROUGHING. HOWEVER...BELIEVE
THE THUNDERSTORM CHANCE IS LOW BECAUSE OF SHALLOW MOISTURE IN THE
WAKE OF THE MID-LEVEL SHORTWAVE TROUGH AND NOCTURNAL COOLING. THE
NAM AND GFS MOS HAVE POPS 20 TO 30 PERCENT...MAINLY IN THE EVENING
CLOSER TO THE TIME OF HEATING. THE TEMPERATURE GUIDANCE WAS CLOSE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

CLOUDINESS ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH AND H85
WIND SPEED CONVERGENCE MAY BRING A PERIOD OF MVFR CEILINGS AT
SOME OF THE TAF SITES. HEATING AND MIXING SHOULD HELP DIMINISH
THIS CLOUDINESS BY MIDDAY. SATELLITE TRENDS AND THE HRRR GUIDANCE
INDICATED A PERIOD OF MVFR AT AGS...DNL...CAE...AND CUB.

SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF THE MID-LEVEL SHORTWAVE TROUGH. THE
TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 191340
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
940 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND STRONG HEATING WILL SUPPORT SCATTERED
THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE THUNDERSTORM
CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO HOTTER HIGH
TEMPERATURES. AN APPROACHING COLD FRONT AND INCREASING MOISTURE
WILL INCREASE THE THUNDERSTORM CHANCE OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
TODAY...SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. THE
TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW.
SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH 5000-FOOT WINDS NEAR
30 KNOTS MAINLY IN THE SOUTH PART AND STEEP LOW-LEVEL LAPSE RATES
MAY HELP SUPPORT STRONG WIND GUSTS WITH ANY THUNDERSTORMS. STRONG
MIXING WILL BRING GUSTY WINDS. USED THE GFS LAMP AND NAM BUFKIT
MOMENTUM-TRANSFER TOOL FOR THE WIND GUST FORECAST. USED THE
WARMER TEMPERATURE GUIDANCE BECAUSE OF THE WESTERLY FLOW.

TONIGHT...THE MODELS MAINTAIN SURFACE TROUGHING. HOWEVER...BELIEVE
THE THUNDERSTORM CHANCE IS LOW BECAUSE OF SHALLOW MOISTURE IN THE
WAKE OF THE MID-LEVEL SHORTWAVE TROUGH AND NOCTURNAL COOLING. THE
NAM AND GFS MOS HAVE POPS 20 TO 30 PERCENT...MAINLY IN THE EVENING
CLOSER TO THE TIME OF HEATING. THE TEMPERATURE GUIDANCE WAS CLOSE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEW POINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

CLOUDINESS ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH AND H85
WIND SPEED CONVERGENCE MAY BRING A PERIOD OF MVFR CEILINGS AT
SOME OF THE TAF SITES. HEATING AND MIXING SHOULD HELP DIMINISH
THIS CLOUDINESS BY MIDDAY. SATELLITE TRENDS AND THE HRRR GUIDANCE
INDICATED A PERIOD OF MVFR AT AGS...DNL...CAE...AND CUB.

SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF THE MID-LEVEL SHORTWAVE TROUGH. THE
TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY AND BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND
TIMING UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST. DRYING ALOFT AND LINGERING LOW-LEVEL MOISTURE PLUS
NOCTURNAL COOLING MAY HELP SUPPORT FOG TONIGHT. MOST OF THE NAM
AND GFS MOS INDICATE MVFR FOG. FOG WILL LIKELY BE LIMITED BY SOME
MIXING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 191208
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
808 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS TODAY. DRIER AIR AND A BUILDING UPPER
RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON THUNDERSTORM CHANCES
WEDNESDAY AND THURSDAY...AND LEAD TO INCREASING HIGH TEMPERATURES.
AN APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
A SHORTWAVE TROUGH CROSSING NORTHERN GA IN NEAR ZONAL FLOW THIS
MORNING IS EXPECTED TO MOVE INTO WESTERN SC AROUND SUNRISE AND
CROSS THE FORECAST AREA TODAY. HAVE INCREASED POPS TO THE 40 TO 50
PERCENT RANGE. WEAK TO MODERATE INSTABILITY IS FORECAST ALONG WITH
PWAT INCREASING TO AROUND OR ABOVE 2.00 INCHES THIS AFTERNOON.
CANNOT RULE OUT AN ISOLATED STRONG TO SEVERE STORM THIS AFTERNOON
GIVEN INVERTED V SIGNATURE INDICATED IN FORECAST SOUNDINGS FOR THE
AFTERNOON. DAMAGING WIND GUSTS WOULD BE THE MAIN THREAT IF A
SEVERE STORM DEVELOPS WITH LARGE HAIL GENERALLY UNLIKELY DUE TO
FREEZING LEVEL HEIGHT OVER 15KFT. THE CENTRAL AND SOUTHEASTERN
MIDLANDS AND CSRA LOOK TO BE THE MOST FAVORABLE LOCATION FOR
STORMS TODAY. KEPT AFTERNOON HIGHS ON THE WARM SIDE OF GUIDANCE.
CONVECTION WILL DECREASE EARLY THIS EVENING AS THE SHORT WAVE
MOVES EAST OF THE AREA. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO
THE LOWER 70S AS SKIES BECOME MOSTLY CLEAR.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEWPOINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
NO SIGNIFICANT CHANGES MADE TO THE LONG TERM FORECAST.

PREVIOUS DISCUSSION:
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

H85 WIND SPEED CONVERGENCE MAY HELP SUPPORT A PERIOD OF MVFR
CEILINGS THIS MORNING. THE 08Z HRRR INDICATED MVFR CEILINGS FOR A
SHORT PERIOD OF TIME THIS MORNING AT AGS AND DNL. HEATING AND
MIXING SHOULD HELP DIMINISH THIS CLOUDINESS LATER THIS MORNING.
SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF A MID-LEVEL SHORTWAVE TROUGH.
THE TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND TIMING
UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 191208
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
808 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS TODAY. DRIER AIR AND A BUILDING UPPER
RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON THUNDERSTORM CHANCES
WEDNESDAY AND THURSDAY...AND LEAD TO INCREASING HIGH TEMPERATURES.
AN APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
A SHORTWAVE TROUGH CROSSING NORTHERN GA IN NEAR ZONAL FLOW THIS
MORNING IS EXPECTED TO MOVE INTO WESTERN SC AROUND SUNRISE AND
CROSS THE FORECAST AREA TODAY. HAVE INCREASED POPS TO THE 40 TO 50
PERCENT RANGE. WEAK TO MODERATE INSTABILITY IS FORECAST ALONG WITH
PWAT INCREASING TO AROUND OR ABOVE 2.00 INCHES THIS AFTERNOON.
CANNOT RULE OUT AN ISOLATED STRONG TO SEVERE STORM THIS AFTERNOON
GIVEN INVERTED V SIGNATURE INDICATED IN FORECAST SOUNDINGS FOR THE
AFTERNOON. DAMAGING WIND GUSTS WOULD BE THE MAIN THREAT IF A
SEVERE STORM DEVELOPS WITH LARGE HAIL GENERALLY UNLIKELY DUE TO
FREEZING LEVEL HEIGHT OVER 15KFT. THE CENTRAL AND SOUTHEASTERN
MIDLANDS AND CSRA LOOK TO BE THE MOST FAVORABLE LOCATION FOR
STORMS TODAY. KEPT AFTERNOON HIGHS ON THE WARM SIDE OF GUIDANCE.
CONVECTION WILL DECREASE EARLY THIS EVENING AS THE SHORT WAVE
MOVES EAST OF THE AREA. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO
THE LOWER 70S AS SKIES BECOME MOSTLY CLEAR.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEWPOINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
NO SIGNIFICANT CHANGES MADE TO THE LONG TERM FORECAST.

PREVIOUS DISCUSSION:
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

H85 WIND SPEED CONVERGENCE MAY HELP SUPPORT A PERIOD OF MVFR
CEILINGS THIS MORNING. THE 08Z HRRR INDICATED MVFR CEILINGS FOR A
SHORT PERIOD OF TIME THIS MORNING AT AGS AND DNL. HEATING AND
MIXING SHOULD HELP DIMINISH THIS CLOUDINESS LATER THIS MORNING.
SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF A MID-LEVEL SHORTWAVE TROUGH.
THE TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND TIMING
UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 191208
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
808 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS TODAY. DRIER AIR AND A BUILDING UPPER
RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON THUNDERSTORM CHANCES
WEDNESDAY AND THURSDAY...AND LEAD TO INCREASING HIGH TEMPERATURES.
AN APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
A SHORTWAVE TROUGH CROSSING NORTHERN GA IN NEAR ZONAL FLOW THIS
MORNING IS EXPECTED TO MOVE INTO WESTERN SC AROUND SUNRISE AND
CROSS THE FORECAST AREA TODAY. HAVE INCREASED POPS TO THE 40 TO 50
PERCENT RANGE. WEAK TO MODERATE INSTABILITY IS FORECAST ALONG WITH
PWAT INCREASING TO AROUND OR ABOVE 2.00 INCHES THIS AFTERNOON.
CANNOT RULE OUT AN ISOLATED STRONG TO SEVERE STORM THIS AFTERNOON
GIVEN INVERTED V SIGNATURE INDICATED IN FORECAST SOUNDINGS FOR THE
AFTERNOON. DAMAGING WIND GUSTS WOULD BE THE MAIN THREAT IF A
SEVERE STORM DEVELOPS WITH LARGE HAIL GENERALLY UNLIKELY DUE TO
FREEZING LEVEL HEIGHT OVER 15KFT. THE CENTRAL AND SOUTHEASTERN
MIDLANDS AND CSRA LOOK TO BE THE MOST FAVORABLE LOCATION FOR
STORMS TODAY. KEPT AFTERNOON HIGHS ON THE WARM SIDE OF GUIDANCE.
CONVECTION WILL DECREASE EARLY THIS EVENING AS THE SHORT WAVE
MOVES EAST OF THE AREA. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO
THE LOWER 70S AS SKIES BECOME MOSTLY CLEAR.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEWPOINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
NO SIGNIFICANT CHANGES MADE TO THE LONG TERM FORECAST.

PREVIOUS DISCUSSION:
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

H85 WIND SPEED CONVERGENCE MAY HELP SUPPORT A PERIOD OF MVFR
CEILINGS THIS MORNING. THE 08Z HRRR INDICATED MVFR CEILINGS FOR A
SHORT PERIOD OF TIME THIS MORNING AT AGS AND DNL. HEATING AND
MIXING SHOULD HELP DIMINISH THIS CLOUDINESS LATER THIS MORNING.
SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF A MID-LEVEL SHORTWAVE TROUGH.
THE TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND TIMING
UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 191208
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
808 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS TODAY. DRIER AIR AND A BUILDING UPPER
RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON THUNDERSTORM CHANCES
WEDNESDAY AND THURSDAY...AND LEAD TO INCREASING HIGH TEMPERATURES.
AN APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
A SHORTWAVE TROUGH CROSSING NORTHERN GA IN NEAR ZONAL FLOW THIS
MORNING IS EXPECTED TO MOVE INTO WESTERN SC AROUND SUNRISE AND
CROSS THE FORECAST AREA TODAY. HAVE INCREASED POPS TO THE 40 TO 50
PERCENT RANGE. WEAK TO MODERATE INSTABILITY IS FORECAST ALONG WITH
PWAT INCREASING TO AROUND OR ABOVE 2.00 INCHES THIS AFTERNOON.
CANNOT RULE OUT AN ISOLATED STRONG TO SEVERE STORM THIS AFTERNOON
GIVEN INVERTED V SIGNATURE INDICATED IN FORECAST SOUNDINGS FOR THE
AFTERNOON. DAMAGING WIND GUSTS WOULD BE THE MAIN THREAT IF A
SEVERE STORM DEVELOPS WITH LARGE HAIL GENERALLY UNLIKELY DUE TO
FREEZING LEVEL HEIGHT OVER 15KFT. THE CENTRAL AND SOUTHEASTERN
MIDLANDS AND CSRA LOOK TO BE THE MOST FAVORABLE LOCATION FOR
STORMS TODAY. KEPT AFTERNOON HIGHS ON THE WARM SIDE OF GUIDANCE.
CONVECTION WILL DECREASE EARLY THIS EVENING AS THE SHORT WAVE
MOVES EAST OF THE AREA. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO
THE LOWER 70S AS SKIES BECOME MOSTLY CLEAR.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEWPOINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
NO SIGNIFICANT CHANGES MADE TO THE LONG TERM FORECAST.

PREVIOUS DISCUSSION:
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD.

H85 WIND SPEED CONVERGENCE MAY HELP SUPPORT A PERIOD OF MVFR
CEILINGS THIS MORNING. THE 08Z HRRR INDICATED MVFR CEILINGS FOR A
SHORT PERIOD OF TIME THIS MORNING AT AGS AND DNL. HEATING AND
MIXING SHOULD HELP DIMINISH THIS CLOUDINESS LATER THIS MORNING.
SCATTERED SHOWERS WERE MOVING INTO THE AREA THIS MORNING
ASSOCIATED WITH LIFT AHEAD OF A MID-LEVEL SHORTWAVE TROUGH.
THE TROUGH PLUS HEATING AND CONVERGENCE INTO THE LEE-SIDE SURFACE
TROUGH SHOULD HELP SUPPORT THUNDERSTORMS LATER TODAY. THE HIGH
RESOLUTION MODELS INDICATE SCATTERED COVERAGE. THE COVERAGE WILL
PROBABLY REMAIN LIMITED BECAUSE MUCH OF THE UPPER-LEVEL LIFT AHEAD
OF THE SHORTWAVE TROUGH WILL LIKELY OCCUR EARLY BEFORE MAXIMUM
HEATING. ALSO...CONVERGENCE INTO THE SURFACE FEATURE SHOULD REMAIN
WEAK AND FORECAST SOUNDINGS SHOW WESTERLY FLOW THROUGH A DEEP
LAYER WHICH SHOULD HELP KEEP MOISTURE SOMEWHAT SHALLOW. THE
THUNDERSTORM CHANCE IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECASTS AT THIS TIME BECAUSE OF THE SCATTERED COVERAGE AND TIMING
UNCERTAINTY. SIGNIFICANT UNI-DIRECTIONAL WIND SHEAR WITH
5000-FOOT WINDS NEAR 30 KNOTS MAINLY IN THE SOUTH PART AND STEEP
LOW-LEVEL LAPSE RATES MAY HELP SUPPORT STRONG WIND GUSTS NEAR ANY
THUNDERSTORMS. STRONG MIXING WILL BRING GUSTY WINDS. USED THE GFS
LAMP AND NAM BUFKIT MOMENTUM-TRANSFER TOOL FOR THE WIND GUST
FORECAST.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KFFC 191110 AAA
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
710 AM EDT TUE AUG 19 2014

.PREV DISCUSSION... /ISSUED 340 AM EDT TUE AUG 19 2014/

SHORT TERM /TODAY THROUGH WEDNESDAY/...
SHORT WAVES CONTINUE TO PLAY THE MAIN ROLE IN THE FORECAST TODAY.
A STRONG SHORT WAVE MOVING ACROSS N GA THIS MORNING PRODUCING SOME
SHOWERS OVER THE NORTHERN COUNTIES WITH ANOTHER SHORT WAVE EXPECTED FOR
THE AFTERNOON. THIS SHOULD ALLOW FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS WITH MOST THUNDERSTORMS IN THE AFTERNOON AND THE
MOST LIKELY AREA TO BE CENTRAL GA WITH THE AFTERNOON SHORT WAVE.

INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STRONG STORMS AND YOU CAN
NOT RULE OUT ISOLATED SEVERE STORMS...ESPECIALLY FOR CENTRAL GA.

SOME SHOWER AND STORM ACTIVITY WILL GO INTO THE EVENING BEFORE
DIMINISHING...ESPECIALLY OVER CENTRAL GA.

ANOTHER LESS IMPRESSIVE SHORT WAVE APPROACHES N GA LATE TONIGHT AND
COULD AFFECT THE REST OF THE AREA SOME TIME DURING THE DAY
WEDNESDAY. A SURFACE TROUGH WILL HELP TO ENHANCE SHOWER AND STORM
ACTIVITY OVER THE SE COUNTIES DURING THE AFTERNOON.

FORECAST HIGH TEMPERATURES RUNNING NEAR NORMAL TODAY AND 3-6 DEGREES
ABOVE NORMAL FOR WEDNESDAY. FORECAST LOW TEMPERATURES RUNNING NEAR
NORMAL TONIGHT.

OVERALL CONFIDENCE IS MEDIUM.

BDL

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST WEST OF
THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER MISSISSIPPI
VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL ABOVE NORMAL
AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE RIDGE
CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE PULLING
POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT CHANCES WILL
BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-EAST GRADIENT
AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO TURN EASTERLY BY
LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF THE EDGE OFF OF THE
HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

.AVIATION...
12Z UPDATE...
ANY IFR-MVFR CEILINGS EXPECTED TO IMPROVE TO VFR. SHOWER AND
THUNDERSTORM POTENTIAL THROUGHOUT THE DAY WITH TIMING AT ANY TAF
SITE UNCERTAIN. SURFACE WINDS INCREASING TO MAINLY WEST AROUND 10
KTS WITH SOME GUSTS AROUND 20 KTS.

//ATL CONFIDENCE...12Z UPDATE...
LOW CONFIDENCE ON CEILINGS AND IMPACTS OF THUNDERSTORMS.
 TEMPO 1918/1922 VRB15G30KT 3SM TSRA BKN035CBHIGH CONFIDENCE ON WINDS.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          90  70  95  73 /  50  20  20  20
ATLANTA         87  72  91  75 /  40  20  20  20
BLAIRSVILLE     83  66  87  68 /  40  20  30  20
CARTERSVILLE    87  69  92  70 /  40  20  20  20
COLUMBUS        90  73  94  76 /  60  20  20  20
GAINESVILLE     86  71  90  74 /  40  20  20  20
MACON           93  70  94  74 /  50  20  20  20
ROME            87  70  93  71 /  40  20  30  20
PEACHTREE CITY  88  68  92  71 /  40  20  20  20
VIDALIA         95  74  97  76 /  50  30  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...BDL
LONG TERM....20
AVIATION...BDL








000
FXUS62 KCHS 191105
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
705 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
00Z MODELS AGREE ON SHIFTING THE MID LEVEL SHORT WAVE TO A POSITION
BETWEEN COLUMBIA SC AND CHARLOTTE NC BY EARLY THIS AFTERNOON AND
THEN CLOSE TO LITTLE RIVER INLET BY SUNSET. A SECONDARY SURFACE
LOW WILL DEVELOP TO THE NORTH OF OUR AREA THIS AFTERNOON ALONG A
TRAILING SURFACE TROUGH. WHILE THERE IS SUBSTANTIAL THETA-E
ADVECTION PROGGED AT 850 MB LATER THIS MORNING INTO THIS
AFTERNOON... DEVELOPMENT OF DIURNAL CONVECTION MAY EVENTUALLY BE
KEPT IN CHECK SOMEWHAT BY THE DEEP AND SEASONABLY STRONG WEST FLOW
SEEN ON FORECAST SOUNDINGS DURING THE DAY. THE SEA BREEZE SHOULD
BE PINNED SOLID TO THE BEACHES AND BARRIER ISLANDS THROUGH THE
AFTERNOON PERHAPS GETTING THROUGH THE U.S. 17 CORRIDOR OF
CHARLESTON COUNTY LATE DAY AND MAYBE NOT REACHING DOWNTOWN OR MID-
TOWN SAVANNAH AT ALL AS H925 FLOW IS AT LEAST 25 KT THROUGH THE
DAY.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN SOME
AREAS BY MIDDAY...REACHING AT LEAST THE MID 90S. HIGH RESOLUTION
MODELS GENERALLY AGREE ON DEVELOPING W-E BANDS OF SCATTERED SHOWERS
AND TSTMS IN CONJUNCTION WITH THE SAGGING MID LEVEL HEIGHTS AND THE
TAIL OF THE VORT LOBE PASSING BY. SOME OF OUR BETTER PERFORMING
MODELS SUCH AS THE NSSL ARW SUGGEST SCATTERED POPS IS THE WAY TO GO
TODAY AND THIS LED TO ONLY MINOR TWEAKS TO OUR SCHEME.

OF INTEREST TODAY IS THE STRENGTH OF THE LOW LEVEL WIND FIELDS WITH
25 KT OF BULK SHEAR STREAMING THROUGH THE REGION. FORECAST
DOWNDRAFT CAPES DIFFER BY MODEL...BUT IT WOULD APPEAR THAT EITHER
SINGLE CELL OR MULTI-CELL CONVECTION WOULD HAVE A CHANCE TO
PRODUCE SOME GUSTY WINDS WITH SWIFT W-E STORM MOTIONS FOR THIS
TIME OF YEAR. WHILE THERE ARE SOME CRITICAL DIFFERENCES ON FORECAST
PROXIMITY SOUNDINGS BETWEEN VARIOUS GUIDANCE PACKAGES...WE WILL
STILL HIGHLIGHT AN ISOLATED RISK FOR SEVERE WEATHER TODAY IN OUR
HAZARDOUS WEATHER OUTLOOK...MAINLY FOR LOCALIZED DAMAGING WINDS. OUR
CONCERNS WOULD BE CERTAINLY BE GREATER IF WE NOTED MORE ORGANIZED
FORECAST REFLECTIVITY PROGS ON THE 00Z MODEL RUN...THE HIGHEST
CAPES LOOK TO BE DISPLACED OFF THE COAST AND THE OVERALL CONVERGENCE
PATTERN IS MAINLY FOCUSED ALONG STRETCHED MESOSCALE BOUNDARIES AND
HORIZONTAL ROLLS. THIS EVENING...A SECONDARY UPPER DISTURBANCE
WILL FOLLOW THE LEAD SHORT WAVE AND MAY KEEP SOME CONVECTION GOING
A WHILE AFTER SUNSET TO THE EAST OF I-95 IN SOUTH CAROLINA. BY
LATE EVENING...CONDITIONS SHOULD QUIET DOWN WITH A STEADY LOW
LEVEL PRES GRADIENT OVER THE REGION SUGGESTING FOG WILL NOT BE AN
ISSUE.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 12Z WEDNESDAY. SHOWERS/THUNDERSTORMS
ARE EXPECTED TO REDEVELOP THIS AFTERNOON. REDUCED CIGS/VSBYS POSSIBLE
WITHIN ANY THUNDERSTORM THAT DIRECTLY AFFECTS THE TERMINALS. STORM
MOTIONS AND CONVERGENCE BANDS ARE SUCH THAT VCTS WILL CONTINUE TO
BE OUR MENTION OF CHOICE UNTIL RADAR TRENDS DICTATE FUTURE CONVECTIVE
TRENDS. TSTM CHANCES SHOULD DIMINISH LATER THIS EVENING AS EFFECTS
FROM A TRAILING UPPER LEVEL DISTURBANCE HAS PASSED.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
WINDS WILL BE SLOWER TO SUBSIDE ALONG LAND/SEA INTERFACE DURING THE
MORNING HOURS GIVEN THE STRENGTH OF THE LOW LEVEL JET. WE MAINTAINED
A SOLID 15 KT ALL NEAR SHORE WATERS TODAY WITH 15-20 KT IN THE CHS
HARBOR FOR A PERIOD THIS AFTERNOON. TONIGHT...THE NOCTURNAL
JETTING WILL RAMP UP ONCE AGAIN SIMILAR TO THIS MORNING WITH NEAR
20 KT SUSTAINED OVER OUTER GEORGIA WATERS FROM GRAYS REEF SEAWARD.
SEAS NEAR SHORE THROUGH TONIGHT AVERAGING 2-4 FT WITH 3-5 FT
CLOSER TO THE GULF STREAM WATERS OFF THE GEORGIA COAST.

THERE IS NOTHING TO STOP LAND BASED TSTMS FROM SHIFTING OVER THE
WATERS THIS AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE
GUSTY WINDS IN EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES.
CONVECTION OVER THE WATERS WILL DIMINISH LATE IN THE EVENING AND
OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 191105
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
705 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
00Z MODELS AGREE ON SHIFTING THE MID LEVEL SHORT WAVE TO A POSITION
BETWEEN COLUMBIA SC AND CHARLOTTE NC BY EARLY THIS AFTERNOON AND
THEN CLOSE TO LITTLE RIVER INLET BY SUNSET. A SECONDARY SURFACE
LOW WILL DEVELOP TO THE NORTH OF OUR AREA THIS AFTERNOON ALONG A
TRAILING SURFACE TROUGH. WHILE THERE IS SUBSTANTIAL THETA-E
ADVECTION PROGGED AT 850 MB LATER THIS MORNING INTO THIS
AFTERNOON... DEVELOPMENT OF DIURNAL CONVECTION MAY EVENTUALLY BE
KEPT IN CHECK SOMEWHAT BY THE DEEP AND SEASONABLY STRONG WEST FLOW
SEEN ON FORECAST SOUNDINGS DURING THE DAY. THE SEA BREEZE SHOULD
BE PINNED SOLID TO THE BEACHES AND BARRIER ISLANDS THROUGH THE
AFTERNOON PERHAPS GETTING THROUGH THE U.S. 17 CORRIDOR OF
CHARLESTON COUNTY LATE DAY AND MAYBE NOT REACHING DOWNTOWN OR MID-
TOWN SAVANNAH AT ALL AS H925 FLOW IS AT LEAST 25 KT THROUGH THE
DAY.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN SOME
AREAS BY MIDDAY...REACHING AT LEAST THE MID 90S. HIGH RESOLUTION
MODELS GENERALLY AGREE ON DEVELOPING W-E BANDS OF SCATTERED SHOWERS
AND TSTMS IN CONJUNCTION WITH THE SAGGING MID LEVEL HEIGHTS AND THE
TAIL OF THE VORT LOBE PASSING BY. SOME OF OUR BETTER PERFORMING
MODELS SUCH AS THE NSSL ARW SUGGEST SCATTERED POPS IS THE WAY TO GO
TODAY AND THIS LED TO ONLY MINOR TWEAKS TO OUR SCHEME.

OF INTEREST TODAY IS THE STRENGTH OF THE LOW LEVEL WIND FIELDS WITH
25 KT OF BULK SHEAR STREAMING THROUGH THE REGION. FORECAST
DOWNDRAFT CAPES DIFFER BY MODEL...BUT IT WOULD APPEAR THAT EITHER
SINGLE CELL OR MULTI-CELL CONVECTION WOULD HAVE A CHANCE TO
PRODUCE SOME GUSTY WINDS WITH SWIFT W-E STORM MOTIONS FOR THIS
TIME OF YEAR. WHILE THERE ARE SOME CRITICAL DIFFERENCES ON FORECAST
PROXIMITY SOUNDINGS BETWEEN VARIOUS GUIDANCE PACKAGES...WE WILL
STILL HIGHLIGHT AN ISOLATED RISK FOR SEVERE WEATHER TODAY IN OUR
HAZARDOUS WEATHER OUTLOOK...MAINLY FOR LOCALIZED DAMAGING WINDS. OUR
CONCERNS WOULD BE CERTAINLY BE GREATER IF WE NOTED MORE ORGANIZED
FORECAST REFLECTIVITY PROGS ON THE 00Z MODEL RUN...THE HIGHEST
CAPES LOOK TO BE DISPLACED OFF THE COAST AND THE OVERALL CONVERGENCE
PATTERN IS MAINLY FOCUSED ALONG STRETCHED MESOSCALE BOUNDARIES AND
HORIZONTAL ROLLS. THIS EVENING...A SECONDARY UPPER DISTURBANCE
WILL FOLLOW THE LEAD SHORT WAVE AND MAY KEEP SOME CONVECTION GOING
A WHILE AFTER SUNSET TO THE EAST OF I-95 IN SOUTH CAROLINA. BY
LATE EVENING...CONDITIONS SHOULD QUIET DOWN WITH A STEADY LOW
LEVEL PRES GRADIENT OVER THE REGION SUGGESTING FOG WILL NOT BE AN
ISSUE.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 12Z WEDNESDAY. SHOWERS/THUNDERSTORMS
ARE EXPECTED TO REDEVELOP THIS AFTERNOON. REDUCED CIGS/VSBYS POSSIBLE
WITHIN ANY THUNDERSTORM THAT DIRECTLY AFFECTS THE TERMINALS. STORM
MOTIONS AND CONVERGENCE BANDS ARE SUCH THAT VCTS WILL CONTINUE TO
BE OUR MENTION OF CHOICE UNTIL RADAR TRENDS DICTATE FUTURE CONVECTIVE
TRENDS. TSTM CHANCES SHOULD DIMINISH LATER THIS EVENING AS EFFECTS
FROM A TRAILING UPPER LEVEL DISTURBANCE HAS PASSED.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
WINDS WILL BE SLOWER TO SUBSIDE ALONG LAND/SEA INTERFACE DURING THE
MORNING HOURS GIVEN THE STRENGTH OF THE LOW LEVEL JET. WE MAINTAINED
A SOLID 15 KT ALL NEAR SHORE WATERS TODAY WITH 15-20 KT IN THE CHS
HARBOR FOR A PERIOD THIS AFTERNOON. TONIGHT...THE NOCTURNAL
JETTING WILL RAMP UP ONCE AGAIN SIMILAR TO THIS MORNING WITH NEAR
20 KT SUSTAINED OVER OUTER GEORGIA WATERS FROM GRAYS REEF SEAWARD.
SEAS NEAR SHORE THROUGH TONIGHT AVERAGING 2-4 FT WITH 3-5 FT
CLOSER TO THE GULF STREAM WATERS OFF THE GEORGIA COAST.

THERE IS NOTHING TO STOP LAND BASED TSTMS FROM SHIFTING OVER THE
WATERS THIS AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE
GUSTY WINDS IN EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES.
CONVECTION OVER THE WATERS WILL DIMINISH LATE IN THE EVENING AND
OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
EQUIPMENT...






000
FXUS62 KCAE 191043
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
643 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS TODAY. DRIER AIR AND A BUILDING UPPER
RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON THUNDERSTORM CHANCES
WEDNESDAY AND THURSDAY...AND LEAD TO INCREASING HIGH TEMPERATURES.
AN APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
A SHORT WAVE CROSSING NORTHERN GA IN NEAR ZONAL FLOW THIS MORNING
IS EXPECTED TO MOVE INTO WESTERN SC AROUND SUNRISE AND CROSS THE
FORECAST AREA TODAY. HAVE INCREASED POPS TO THE 40 TO 50 PERCENT
RANGE. WEAK TO MODERATE INSTABILITY IS FORECAST ALONG WITH PWAT
INCREASING TO AROUND OR ABOVE 2.00 INCHES THIS AFTERNOON. CANNOT
RULE OUT AN ISOLATED STRONG TO SEVERE STORM THIS AFTERNOON GIVEN
INVERTED V SIGNATURE INDICATED IN FORECAST SOUNDINGS FOR THE
AFTERNOON. DAMAGING WIND GUSTS WOULD BE THE MAIN THREAT IF A
SEVERE STORM DEVELOPS WITH LARGE HAIL GENERALLY UNLIKELY DUE TO
FREEZING LEVEL HEIGHT OVER 15KFT. THE CENTRAL AND SOUTHEASTERN
MIDLANDS AND CSRA LOOK TO BE THE MOST FAVORABLE LOCATION FOR
STORMS TODAY. KEPT AFTERNOON HIGHS ON THE WARM SIDE OF GUIDANCE.
CONVECTION WILL DECREASE EARLY THIS EVENING AS THE SHORT WAVE
MOVES EAST OF THE AREA. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO
THE LOWER 70S AS SKIES BECOME MOSTLY CLEAR.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEWPOINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
NO SIGNIFICANT CHANGES MADE TO THE LONG TERM FORECAST.

PREVIOUS DISCUSSION:
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
EXPECT VFR CONDITIONS TO PERSIST DURING THE TAF PERIOD.

FOG NOT EXPECTED THIS MORNING DUE TO THE 25-30 KNOT LOW-LEVEL JET
NOTED ON KCAE VAD WIND PROFILE. SATELLITE IMAGERY SHOWING SOME
LOWER CLOUDS ASSOCIATED WITH THE NEXT SHORTWAVE OVER NORTHERN
GEORGIA BUT DO NOT EXPECT THEM TO REACH THE TERMINALS BEFORE
DAYTIME HEATING BEGINS.

WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET MIXES DOWN
ASSOCIATED WITH SURFACE HEATING BY 15Z. EXPECT GUSTS AROUND 20
KNOTS THROUGH THE AFTERNOON HOURS. THERE REMAINS A CHANCE FOR
AFTERNOON SHOWERS/STORMS ACROSS THE REGION TUESDAY. MOS GUIDANCE
IS HINTING AT SOME POSSIBLE MVFR FOG AT OGB/AGS BUT NOT CONFIDENT
ENOUGH TO ADD TO FORECAST AT THIS POINT WITH DOWNSLOPING FLOW
DEVELOPING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 191043
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
643 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS TODAY. DRIER AIR AND A BUILDING UPPER
RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON THUNDERSTORM CHANCES
WEDNESDAY AND THURSDAY...AND LEAD TO INCREASING HIGH TEMPERATURES.
AN APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
A SHORT WAVE CROSSING NORTHERN GA IN NEAR ZONAL FLOW THIS MORNING
IS EXPECTED TO MOVE INTO WESTERN SC AROUND SUNRISE AND CROSS THE
FORECAST AREA TODAY. HAVE INCREASED POPS TO THE 40 TO 50 PERCENT
RANGE. WEAK TO MODERATE INSTABILITY IS FORECAST ALONG WITH PWAT
INCREASING TO AROUND OR ABOVE 2.00 INCHES THIS AFTERNOON. CANNOT
RULE OUT AN ISOLATED STRONG TO SEVERE STORM THIS AFTERNOON GIVEN
INVERTED V SIGNATURE INDICATED IN FORECAST SOUNDINGS FOR THE
AFTERNOON. DAMAGING WIND GUSTS WOULD BE THE MAIN THREAT IF A
SEVERE STORM DEVELOPS WITH LARGE HAIL GENERALLY UNLIKELY DUE TO
FREEZING LEVEL HEIGHT OVER 15KFT. THE CENTRAL AND SOUTHEASTERN
MIDLANDS AND CSRA LOOK TO BE THE MOST FAVORABLE LOCATION FOR
STORMS TODAY. KEPT AFTERNOON HIGHS ON THE WARM SIDE OF GUIDANCE.
CONVECTION WILL DECREASE EARLY THIS EVENING AS THE SHORT WAVE
MOVES EAST OF THE AREA. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO
THE LOWER 70S AS SKIES BECOME MOSTLY CLEAR.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEWPOINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
NO SIGNIFICANT CHANGES MADE TO THE LONG TERM FORECAST.

PREVIOUS DISCUSSION:
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
EXPECT VFR CONDITIONS TO PERSIST DURING THE TAF PERIOD.

FOG NOT EXPECTED THIS MORNING DUE TO THE 25-30 KNOT LOW-LEVEL JET
NOTED ON KCAE VAD WIND PROFILE. SATELLITE IMAGERY SHOWING SOME
LOWER CLOUDS ASSOCIATED WITH THE NEXT SHORTWAVE OVER NORTHERN
GEORGIA BUT DO NOT EXPECT THEM TO REACH THE TERMINALS BEFORE
DAYTIME HEATING BEGINS.

WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET MIXES DOWN
ASSOCIATED WITH SURFACE HEATING BY 15Z. EXPECT GUSTS AROUND 20
KNOTS THROUGH THE AFTERNOON HOURS. THERE REMAINS A CHANCE FOR
AFTERNOON SHOWERS/STORMS ACROSS THE REGION TUESDAY. MOS GUIDANCE
IS HINTING AT SOME POSSIBLE MVFR FOG AT OGB/AGS BUT NOT CONFIDENT
ENOUGH TO ADD TO FORECAST AT THIS POINT WITH DOWNSLOPING FLOW
DEVELOPING.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCHS 190825
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
425 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
OVERNIGHT A CLUSTER OF MULTICELL TSTMS MOVED FAR AWAY FROM THE
SOUTH CAROLINA COAST WHILE QUIET CONDITIONS PREVAILED WITH MAINLY
HIGH THIN CLOUDS AND A BIT OF AN OVERNIGHT BREEZE COURTESY OF A
DECENT GRADIENT AT THE SURFACE AND IN THE LOWEST LEVELS. A MID
LEVEL SHORT WAVE WAS MOVING INTO NORTH GEORGIA...A FEW SHOWERS
COULD BREAK OUT TOWARD DAYBREAK OVER EAST CENTRAL GEORGIA OR THE
CSRA...WE KEEP OUR INLAND ZONES DRY. TEMPS IN THE MID TO UPPER 70S
ONCE AGAIN.

12Z MODELS AGREE ON SHIFTING THE MID LEVEL SHORT WAVE TO A POSITION
BETWEEN COLUMBIA SC AND CHARLOTTE NC BY EARLY THIS AFTERNOON AND
THEN CLOSE TO LITTLE RIVER INLET BY SUNSET. A SECONDARY SURFACE
LOW WILL DEVELOP TO THE NORTH OF OUR AREA THIS AFTERNOON ALONG A
TRAILING SURFACE TROUGH. WHILE THERE IS SUBSTANTIAL THETA-E
ADVECTION PROGGED AT 850 MB LATER THIS MORNING INTO THIS AFTERNOON...
DEVELOPMENT OF DIURNAL CONVECTION MAY EVENTUALLY BE KEPT IN CHECK
SOMEWHAT BY THE DEEP AND SEASONABLY STRONG WEST FLOW SEEN ON
FORECAST SOUNDINGS DURING THE DAY. THE SEA BREEZE SHOULD BE PINNED
SOLID TO THE BEACHES AND BARRIER ISLANDS THROUGH THE AFTERNOON
PERHAPS GETTING THROUGH THE U.S. 17 CORRIDOR OF CHARLESTON COUNTY
LATE DAY AND MAYBE NOT REACHING DOWNTOWN OR MID-TOWN SAVANNAH AT
ALL AS H925 FLOW IS AT LEAST 25 KT THROUGH THE DAY.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN SOME
AREAS BY MIDDAY...REACHING AT LEAST THE MID 90S. HIGH RESOLUTION
MODELS GENERALLY AGREE ON DEVELOPING W-E BANDS OF SCATTERED SHOWERS
AND TSTMS IN CONJUNCTION WITH THE SAGGING MID LEVEL HEIGHTS AND THE
TAIL OF THE VORT LOBE PASSING BY. SOME OF OUR BETTER PERFORMING
MODELS SUCH AS THE NSSL ARW SUGGEST SCATTERED POPS IS THE WAY TO GO
TODAY AND THIS LED TO ONLY MINOR TWEAKS TO OUR SCHEME.

OF INTEREST TODAY IS THE STRENGTH OF THE LOW LEVEL WIND FIELDS WITH
25 KT OF BULK SHEAR STREAMING THROUGH THE REGION. FORECAST
DOWNDRAFT CAPES DIFFER BY MODEL...BUT IT WOULD APPEAR THAT EITHER
SINGLE CELL OR MULTI-CELL CONVECTION WOULD HAVE A CHANCE TO
PRODUCE SOME GUSTY WINDS WITH SWIFT W-E STORM MOTIONS FOR THIS
TIME OF YEAR. WHILE THERE ARE SOME CRITICAL DIFFERENCES ON FORECAST
PROXIMITY SOUNDINGS BETWEEN VARIOUS GUIDANCE PACKAGES...WE WILL
STILL HIGHLIGHT AN ISOLATED RISK FOR SEVERE WEATHER TODAY IN OUR
HAZARDOUS WEATHER OUTLOOK...MAINLY FOR LOCALIZED DAMAGING WINDS. OUR
CONCERNS WOULD BE CERTAINLY BE GREATER IF WE NOTED MORE ORGANIZED
FORECAST REFLECTIVITY PROGS ON THE 00Z MODEL RUN...THE HIGHEST
CAPES LOOK TO BE DISPLACED OFF THE COAST AND THE OVERALL CONVERGENCE
PATTERN IS MAINLY FOCUSED ALONG STRETCHED MESOSCALE BOUNDARIES AND
HORIZONTAL ROLLS. THIS EVENING...A SECONDARY UPPER DISTURBANCE
WILL FOLLOW THE LEAD SHORT WAVE AND MAY KEEP SOME CONVECTION GOING
A WHILE AFTER SUNSET TO THE EAST OF I-95 IN SOUTH CAROLINA. BY
LATE EVENING...CONDITIONS SHOULD QUIET DOWN WITH A STEADY LOW
LEVEL PRES GRADIENT OVER THE REGION SUGGESTING FOG WILL NOT BE AN
ISSUE.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 06Z WEDNESDAY. SHOWERS/THUNDERSTORMS
ARE EXPECTED TO REDEVELOP THIS AFTERNOON. REDUCED CIGS/VSBYS POSSIBLE
WITHIN ANY THUNDERSTORM THAT DIRECTLY AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
WINDS WILL BE SLOWER TO SUBSIDE ALONG LAND/SEA INTERFACE DURING THE
MORNING HOURS GIVEN THE STRENGTH OF THE LOW LEVEL JET. WE MAINTAINED
A SOLID 15 KT ALL NEAR SHORE WATERS TODAY WITH 15-20 KT IN THE CHS
HARBOR FOR A PERIOD THIS AFTERNOON. TONIGHT...THE NOCTURNAL
JETTING WILL RAMP UP ONCE AGAIN SIMILAR TO THIS MORNING WITH NEAR
20 KT SUSTAINED OVER OUTER GEORGIA WATERS FROM GRAYS REEF SEAWARD.
SEAS NEAR SHORE THROUGH TONIGHT AVERAGING 2-4 FT WITH 3-5 FT
CLOSER TO THE GULF STREAM WATERS OFF THE GEORGIA COAST.

THERE IS NOTHING TO STOP LAND BASED TSTMS FROM SHIFTING OVER THE
WATERS THIS AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE
GUSTY WINDS IN EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES.
CONVECTION OVER THE WATERS WILL DIMINISH LATE IN THE EVENING AND
OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 190825
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
425 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST OF
THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND. A COLD
FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN HIGH PRESSURE
WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
OVERNIGHT A CLUSTER OF MULTICELL TSTMS MOVED FAR AWAY FROM THE
SOUTH CAROLINA COAST WHILE QUIET CONDITIONS PREVAILED WITH MAINLY
HIGH THIN CLOUDS AND A BIT OF AN OVERNIGHT BREEZE COURTESY OF A
DECENT GRADIENT AT THE SURFACE AND IN THE LOWEST LEVELS. A MID
LEVEL SHORT WAVE WAS MOVING INTO NORTH GEORGIA...A FEW SHOWERS
COULD BREAK OUT TOWARD DAYBREAK OVER EAST CENTRAL GEORGIA OR THE
CSRA...WE KEEP OUR INLAND ZONES DRY. TEMPS IN THE MID TO UPPER 70S
ONCE AGAIN.

12Z MODELS AGREE ON SHIFTING THE MID LEVEL SHORT WAVE TO A POSITION
BETWEEN COLUMBIA SC AND CHARLOTTE NC BY EARLY THIS AFTERNOON AND
THEN CLOSE TO LITTLE RIVER INLET BY SUNSET. A SECONDARY SURFACE
LOW WILL DEVELOP TO THE NORTH OF OUR AREA THIS AFTERNOON ALONG A
TRAILING SURFACE TROUGH. WHILE THERE IS SUBSTANTIAL THETA-E
ADVECTION PROGGED AT 850 MB LATER THIS MORNING INTO THIS AFTERNOON...
DEVELOPMENT OF DIURNAL CONVECTION MAY EVENTUALLY BE KEPT IN CHECK
SOMEWHAT BY THE DEEP AND SEASONABLY STRONG WEST FLOW SEEN ON
FORECAST SOUNDINGS DURING THE DAY. THE SEA BREEZE SHOULD BE PINNED
SOLID TO THE BEACHES AND BARRIER ISLANDS THROUGH THE AFTERNOON
PERHAPS GETTING THROUGH THE U.S. 17 CORRIDOR OF CHARLESTON COUNTY
LATE DAY AND MAYBE NOT REACHING DOWNTOWN OR MID-TOWN SAVANNAH AT
ALL AS H925 FLOW IS AT LEAST 25 KT THROUGH THE DAY.

IT/LL BE ANOTHER HOT DAY WITH TEMPS WARMING TO THE LOWER 90S IN SOME
AREAS BY MIDDAY...REACHING AT LEAST THE MID 90S. HIGH RESOLUTION
MODELS GENERALLY AGREE ON DEVELOPING W-E BANDS OF SCATTERED SHOWERS
AND TSTMS IN CONJUNCTION WITH THE SAGGING MID LEVEL HEIGHTS AND THE
TAIL OF THE VORT LOBE PASSING BY. SOME OF OUR BETTER PERFORMING
MODELS SUCH AS THE NSSL ARW SUGGEST SCATTERED POPS IS THE WAY TO GO
TODAY AND THIS LED TO ONLY MINOR TWEAKS TO OUR SCHEME.

OF INTEREST TODAY IS THE STRENGTH OF THE LOW LEVEL WIND FIELDS WITH
25 KT OF BULK SHEAR STREAMING THROUGH THE REGION. FORECAST
DOWNDRAFT CAPES DIFFER BY MODEL...BUT IT WOULD APPEAR THAT EITHER
SINGLE CELL OR MULTI-CELL CONVECTION WOULD HAVE A CHANCE TO
PRODUCE SOME GUSTY WINDS WITH SWIFT W-E STORM MOTIONS FOR THIS
TIME OF YEAR. WHILE THERE ARE SOME CRITICAL DIFFERENCES ON FORECAST
PROXIMITY SOUNDINGS BETWEEN VARIOUS GUIDANCE PACKAGES...WE WILL
STILL HIGHLIGHT AN ISOLATED RISK FOR SEVERE WEATHER TODAY IN OUR
HAZARDOUS WEATHER OUTLOOK...MAINLY FOR LOCALIZED DAMAGING WINDS. OUR
CONCERNS WOULD BE CERTAINLY BE GREATER IF WE NOTED MORE ORGANIZED
FORECAST REFLECTIVITY PROGS ON THE 00Z MODEL RUN...THE HIGHEST
CAPES LOOK TO BE DISPLACED OFF THE COAST AND THE OVERALL CONVERGENCE
PATTERN IS MAINLY FOCUSED ALONG STRETCHED MESOSCALE BOUNDARIES AND
HORIZONTAL ROLLS. THIS EVENING...A SECONDARY UPPER DISTURBANCE
WILL FOLLOW THE LEAD SHORT WAVE AND MAY KEEP SOME CONVECTION GOING
A WHILE AFTER SUNSET TO THE EAST OF I-95 IN SOUTH CAROLINA. BY
LATE EVENING...CONDITIONS SHOULD QUIET DOWN WITH A STEADY LOW
LEVEL PRES GRADIENT OVER THE REGION SUGGESTING FOG WILL NOT BE AN
ISSUE.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
A HOT PATTERN IS IN STORE FOR THE MID-TERM PERIOD DUE TO STRONG
UPPER RIDGING AND DEEP WESTERLY FLOW. ALTHOUGH SOME MID LEVEL
CAPPING WILL BE PRESENT...WEAK SHORTWAVE PERTURBATIONS ROTATING
AROUND THE UPPER RIDGE EACH DAY WILL SUPPORT ISOLATED MAINLY
AFTERNOON AND EVENING SHOWERS AND TSTMS. HIGH TEMPS ALL THREE DAYS
WILL BE IN THE UPPER 90S...THOUGH THURSDAY LOOKS THE WARMEST DUE TO
THE GREATEST UPPER HEIGHTS AND STRONGEST DOWNSLOPE FLOW. A FEW
TRIPLE DIGIT READINGS ARE EXPECTED ACROSS INLAND AREAS ON THURSDAY.
MODEL SOUNDINGS SHOW SOME DRIER AIR MIXING DOWN DURING THE HOURS OF
PEAK HEATING...SO THE BEST CHANCE OF ANY AREAS HITTING A HEAT INDEX
OF 110 WOULD BE MID TO LATE AFTERNOON WITHIN 50 OR SO MILES OF THE
COAST WHEN THE SEA BREEZE MOVES INLAND. FOR NOW WE ARE SHOWING MAX
HEAT INDICES OF 105 TO 109 ALL THREE DAYS AND WILL MAINTAIN A MENTION
OF POSSIBLE HEAT ADVISORIES IN THE HAZARDOUS WEATHER OUTLOOK.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 06Z WEDNESDAY. SHOWERS/THUNDERSTORMS
ARE EXPECTED TO REDEVELOP THIS AFTERNOON. REDUCED CIGS/VSBYS POSSIBLE
WITHIN ANY THUNDERSTORM THAT DIRECTLY AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...MAINLY VFR WED THROUGH FRI. INCREASING
CHANCES FOR FLIGHT RESTRICTIONS SAT INTO SUN AS A FRONT DROPS
THROUGH. COULD SEE SOME LOW CEILINGS AND/OR VSBYS WITH THE FRONT
ALONG WITH INCREASING CHANCES FOR SHOWERS AND TSTMS.

&&

.MARINE...
WINDS WILL BE SLOWER TO SUBSIDE ALONG LAND/SEA INTERFACE DURING THE
MORNING HOURS GIVEN THE STRENGTH OF THE LOW LEVEL JET. WE MAINTAINED
A SOLID 15 KT ALL NEAR SHORE WATERS TODAY WITH 15-20 KT IN THE CHS
HARBOR FOR A PERIOD THIS AFTERNOON. TONIGHT...THE NOCTURNAL
JETTING WILL RAMP UP ONCE AGAIN SIMILAR TO THIS MORNING WITH NEAR
20 KT SUSTAINED OVER OUTER GEORGIA WATERS FROM GRAYS REEF SEAWARD.
SEAS NEAR SHORE THROUGH TONIGHT AVERAGING 2-4 FT WITH 3-5 FT
CLOSER TO THE GULF STREAM WATERS OFF THE GEORGIA COAST.

THERE IS NOTHING TO STOP LAND BASED TSTMS FROM SHIFTING OVER THE
WATERS THIS AFTERNOON AND EVENING. SOME OF STORMS COULD PRODUCE
GUSTY WINDS IN EXCESS OF 35 KT AND DEADLY LIGHTNING STRIKES.
CONVECTION OVER THE WATERS WILL DIMINISH LATE IN THE EVENING AND
OVERNIGHT.

SW FLOW WILL PREVAIL WEDNESDAY THROUGH FRIDAY BEFORE WINDS SWITCH
AROUND TO NE OR ENE BEHIND A COLD FRONT OVER THE WEEKEND. OCCASIONAL
WIND SURGES ARE POSSIBLE THOUGH IN GENERAL WINDS WILL BE LESS THAN
15 KT WITH SEAS LESS THAN 4 FT.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
CLIMATE...
EQUIPMENT...







000
FXUS62 KCAE 190820
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
420 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS TODAY. DRIER AIR AND A BUILDING UPPER
RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON THUNDERSTORM CHANCES
WEDNESDAY AND THURSDAY...AND LEAD TO INCREASING HIGH TEMPERATURES.
AN APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
A SHORT WAVE CROSSING NORTHERN GA IN NEAR ZONAL FLOW THIS MORNING
IS EXPECTED TO MOVE INTO WESTERN SC AROUND SUNRISE AND CROSS THE
FORECAST AREA TODAY. HAVE INCREASED POPS TO THE 40 TO 50 PERCENT
RANGE. WEAK TO MODERATE INSTABILITY IS FORECAST ALONG WITH PWAT
INCREASING TO AROUND OR ABOVE 2.00 INCHES THIS AFTERNOON. CANNOT
RULE OUT AN ISOLATED STRONG TO SEVERE STORM THIS AFTERNOON GIVEN
INVERTED V SIGNATURE INDICATED IN FORECAST SOUNDINGS FOR THE
AFTERNOON. DAMAGING WIND GUSTS WOULD BE THE MAIN THREAT IF A
SEVERE STORM DEVELOPS WITH LARGE HAIL GENERALLY UNLIKELY DUE TO
FREEZING LEVEL HEIGHT OVER 15KFT. THE CENTRAL AND SOUTHEASTERN
MIDLANDS AND CSRA LOOK TO BE THE MOST FAVORABLE LOCATION FOR
STORMS TODAY. KEPT AFTERNOON HIGHS ON THE WARM SIDE OF GUIDANCE.
CONVECTION WILL DECREASE EARLY THIS EVENING AS THE SHORT WAVE
MOVES EAST OF THE AREA. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO
THE LOWER 70S AS SKIES BECOME MOSTLY CLEAR.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
UPPER RIDGE WILL BUILD JUST TO OUR WEST WEDNESDAY AS THE UPPER
TROUGH MOVES OFF THE COAST. WARMING 850MB TEMPERATURES AND A LOW
LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX TEMPERATURES PUSHING 100
DEGREES WEDNESDAY AND THURSDAY. GUIDANCE INDICATES DEWPOINTS
MIXING DOWN INTO THE MID TO UPPER 60S ACROSS THE NORTHERN AND
WESTERN COUNTIES TO NEAR 70 ACROSS THE SOUTHEAST MIDLANDS. THIS
SHOULD KEEP HEAT INDICES JUST BELOW OUR HEAT ADVISORY CRITERIA OF
110F. ONLY SLIGHT CHANCE OF SHOWERS/TSTMS EXPECTED BOTH WEDNESDAY
AND THURSDAY DUE TO DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
NO SIGNIFICANT CHANGES MADE TO THE LONG TERM FORECAST.

PREVIOUS DISCUSSION:
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE
DOWN THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS
WOULD INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO
COOLER TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING
FORECAST OF POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING
THAT TIME.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
EXPECT VFR CONDITIONS TO PERSIST DURING THE TAF PERIOD. ABUNDANT
LOW LEVEL MOISTURE IN PLACE OVERNIGHT BUT NOT EXPECTING
FOG/STRATUS DUE TO THE 25-30 KNOT LOW-LEVEL JET NOTED ON KCAE VAD
WIND PROFILE...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE.

WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET MIXES DOWN
ASSOCIATED WITH SURFACE HEATING BY 15Z. EXPECT GUSTS AROUND 20
KNOTS THROUGH THE AFTERNOON HOURS. THERE REMAINS A CHANCE FOR
AFTERNOON SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KFFC 190740
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
340 AM EDT TUE AUG 19 2014

.SHORT TERM /TODAY THROUGH WEDNESDAY/...
SHORT WAVES CONTINUE TO PLAY THE MAIN ROLE IN THE FORECAST TODAY.
A STRONG SHORT WAVE MOVING ACROSS N GA THIS MORNING PRODUCING SOME
SHOWERS OVER THE NRN COUNTIES WITH ANOTHER SHORT WAVE EXPECTED FOR
THE AFTERNOON. THIS SHOULD ALLOW FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS WITH MOST THUNDERSTORMS IN THE AFTERNOON AND THE
MOST LIKELY AREA TO BE CENTRAL GA WITH THE AFTERNOON SHORT WAVE.

INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STRONG STORMS AND YOU CAN
NOT RULE OUT ISOLATED SEVERE STORMS...ESPECIALLY FOR CENTRAL GA.

SOME SHOWER AND STORM ACTIVITY WILL GO INTO THE EVENING BEFORE
DIMINISHING...ESPECIALLY OVER CENTRAL GA.

ANOTHER LESS IMPRESSIVE SHORT WAVE APPROACHES N GA LATE TONIGHT AND
COULD AFFECT THE REST OF THE AREA SOME TIME DURING THE DAY
WEDNESDAY. A SURFACE TROUGH WILL HELP TO ENHANCE SHOWER AND STORM
ACTIVITY OVER THE SE COUNTIES DURING THE AFTERNOON.

FORECAST HIGH TEMPERATURES RUNNING NEAR NORMAL TODAY AND 3-6 DEGREES
ABOVE NORMAL FOR WEDNESDAY. FORECAST LOW TEMPERATURES RUNNING NEAR
NORMAL TONIGHT.

OVERALL CONFIDENCE IS MEDIUM.

BDL

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST WEST OF
THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER MISSISSIPPI
VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL ABOVE NORMAL
AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE RIDGE
CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE PULLING
POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT CHANCES WILL
BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-EAST GRADIENT
AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO TURN EASTERLY BY
LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF THE EDGE OFF OF THE
HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
06Z UPDATE...
POTENTIAL FOR INCREASING LIFR-MVFR CEILINGS ACROSS THE TAF SITES
WITH SOME MVFR VSBYS DUE TO FOG. IMPROVEMENT EXPECTED TO VFR DURING
THE LATER MORNING. POTENTIAL FOR SHOWERS AND THUNDERSTORMS ALMOST
ANY TIME TODAY. SURFACE WINDS LIGHT WSW INCREASING TO MAINLY WEST
AROUND 10 KTS WITH SOME GUSTS AROUND 20 KTS.

//ATL CONFIDENCE...06Z UPDATE...
LOW CONFIDENCE ON CEILINGS/VSBYS AND IMPACTS OF THUNDERSTORMS TODAY.
HIGH CONFIDENCE ON WINDS.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          90  70  95  73 /  50  20  20  20
ATLANTA         87  72  91  75 /  40  20  20  20
BLAIRSVILLE     83  66  87  68 /  40  20  30  20
CARTERSVILLE    87  69  92  70 /  40  20  20  20
COLUMBUS        90  73  94  76 /  60  20  20  20
GAINESVILLE     86  71  90  74 /  40  20  20  20
MACON           93  70  94  74 /  50  20  20  20
ROME            87  70  93  71 /  40  20  30  20
PEACHTREE CITY  88  68  92  71 /  40  20  20  20
VIDALIA         95  74  97  76 /  50  30  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...BDL
LONG TERM....20
AVIATION...BDL






000
FXUS62 KFFC 190740
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
340 AM EDT TUE AUG 19 2014

.SHORT TERM /TODAY THROUGH WEDNESDAY/...
SHORT WAVES CONTINUE TO PLAY THE MAIN ROLE IN THE FORECAST TODAY.
A STRONG SHORT WAVE MOVING ACROSS N GA THIS MORNING PRODUCING SOME
SHOWERS OVER THE NRN COUNTIES WITH ANOTHER SHORT WAVE EXPECTED FOR
THE AFTERNOON. THIS SHOULD ALLOW FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS WITH MOST THUNDERSTORMS IN THE AFTERNOON AND THE
MOST LIKELY AREA TO BE CENTRAL GA WITH THE AFTERNOON SHORT WAVE.

INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STRONG STORMS AND YOU CAN
NOT RULE OUT ISOLATED SEVERE STORMS...ESPECIALLY FOR CENTRAL GA.

SOME SHOWER AND STORM ACTIVITY WILL GO INTO THE EVENING BEFORE
DIMINISHING...ESPECIALLY OVER CENTRAL GA.

ANOTHER LESS IMPRESSIVE SHORT WAVE APPROACHES N GA LATE TONIGHT AND
COULD AFFECT THE REST OF THE AREA SOME TIME DURING THE DAY
WEDNESDAY. A SURFACE TROUGH WILL HELP TO ENHANCE SHOWER AND STORM
ACTIVITY OVER THE SE COUNTIES DURING THE AFTERNOON.

FORECAST HIGH TEMPERATURES RUNNING NEAR NORMAL TODAY AND 3-6 DEGREES
ABOVE NORMAL FOR WEDNESDAY. FORECAST LOW TEMPERATURES RUNNING NEAR
NORMAL TONIGHT.

OVERALL CONFIDENCE IS MEDIUM.

BDL

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST PERIOD SHOWING A LARGE UPPER RIDGE CENTERED JUST WEST OF
THE STATE ACROSS THE CENTRAL GULF COAST AND LOWER MISSISSIPPI
VALLEY. THIS SHOULD BRING AN EXTENDED PERIOD OF WELL ABOVE NORMAL
AFTERNOON TEMPERATURES TO THE FORECAST AREA. WITH THE RIDGE
CENTERED WEST OF THE AREA I STILL DO NOT FEEL COMFORTABLE PULLING
POPS OUT OF THE FORECAST COMPLETELY AT THIS TIME...BUT CHANCES WILL
BE CONFINED TO SLIGHT CHANCE/LOW CHANCE WITH A WEST-EAST GRADIENT
AND A DIURNAL BIAS. LOW-LEVEL FLOW IS FORECAST TO TURN EASTERLY BY
LATE IN THE WEEKEND WHICH SHOULD TAKE A BIT OF THE EDGE OFF OF THE
HOT TEMPERATURES HEADING INTO EARLY NEXT WEEK.

20

&&

AVIATION...
06Z UPDATE...
POTENTIAL FOR INCREASING LIFR-MVFR CEILINGS ACROSS THE TAF SITES
WITH SOME MVFR VSBYS DUE TO FOG. IMPROVEMENT EXPECTED TO VFR DURING
THE LATER MORNING. POTENTIAL FOR SHOWERS AND THUNDERSTORMS ALMOST
ANY TIME TODAY. SURFACE WINDS LIGHT WSW INCREASING TO MAINLY WEST
AROUND 10 KTS WITH SOME GUSTS AROUND 20 KTS.

//ATL CONFIDENCE...06Z UPDATE...
LOW CONFIDENCE ON CEILINGS/VSBYS AND IMPACTS OF THUNDERSTORMS TODAY.
HIGH CONFIDENCE ON WINDS.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          90  70  95  73 /  50  20  20  20
ATLANTA         87  72  91  75 /  40  20  20  20
BLAIRSVILLE     83  66  87  68 /  40  20  30  20
CARTERSVILLE    87  69  92  70 /  40  20  20  20
COLUMBUS        90  73  94  76 /  60  20  20  20
GAINESVILLE     86  71  90  74 /  40  20  20  20
MACON           93  70  94  74 /  50  20  20  20
ROME            87  70  93  71 /  40  20  30  20
PEACHTREE CITY  88  68  92  71 /  40  20  20  20
VIDALIA         95  74  97  76 /  50  30  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...BDL
LONG TERM....20
AVIATION...BDL





000
FXUS62 KCAE 190531
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
131 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CONVECTION HAS ENDED FOR THE NIGHT AS THE AIRMASS STABILIZES. STILL
WATCHING A SHORT WAVE CROSSING NORTHEAST ALABAMA THAT IS EXPECTED
TO MOVE INTO WESTERN SC AROUND SUNRISE. WILL FORECAST DRY CONDITIONS
FOR THE REMAINDER OF THE NIGHT. SOME CLOUDINESS AND MIXING SHOULD
HELP HOLD UP TEMPERATURES IN THE LOW TO MID 70S OVERNIGHT.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
EXPECT VFR CONDITIONS TO PERSIST DURING THE TAF PERIOD. ABUNDANT
LOW LEVEL MOISTURE IN PLACE OVERNIGHT BUT NOT EXPECTING
FOG/STRATUS DUE TO THE 25-30 KNOT LOW-LEVEL JET NOTED ON KCAE VAD
WIND PROFILE...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE.

WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET MIXES DOWN
ASSOCIATED WITH SURFACE HEATING BY 15Z. EXPECT GUSTS AROUND 20
KNOTS THROUGH THE AFTERNOON HOURS. THERE REMAINS A CHANCE FOR
AFTERNOON SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$










000
FXUS62 KCAE 190531
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
131 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CONVECTION HAS ENDED FOR THE NIGHT AS THE AIRMASS STABILIZES. STILL
WATCHING A SHORT WAVE CROSSING NORTHEAST ALABAMA THAT IS EXPECTED
TO MOVE INTO WESTERN SC AROUND SUNRISE. WILL FORECAST DRY CONDITIONS
FOR THE REMAINDER OF THE NIGHT. SOME CLOUDINESS AND MIXING SHOULD
HELP HOLD UP TEMPERATURES IN THE LOW TO MID 70S OVERNIGHT.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
EXPECT VFR CONDITIONS TO PERSIST DURING THE TAF PERIOD. ABUNDANT
LOW LEVEL MOISTURE IN PLACE OVERNIGHT BUT NOT EXPECTING
FOG/STRATUS DUE TO THE 25-30 KNOT LOW-LEVEL JET NOTED ON KCAE VAD
WIND PROFILE...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE.

WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET MIXES DOWN
ASSOCIATED WITH SURFACE HEATING BY 15Z. EXPECT GUSTS AROUND 20
KNOTS THROUGH THE AFTERNOON HOURS. THERE REMAINS A CHANCE FOR
AFTERNOON SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$










000
FXUS62 KCAE 190531
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
131 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CONVECTION HAS ENDED FOR THE NIGHT AS THE AIRMASS STABILIZES. STILL
WATCHING A SHORT WAVE CROSSING NORTHEAST ALABAMA THAT IS EXPECTED
TO MOVE INTO WESTERN SC AROUND SUNRISE. WILL FORECAST DRY CONDITIONS
FOR THE REMAINDER OF THE NIGHT. SOME CLOUDINESS AND MIXING SHOULD
HELP HOLD UP TEMPERATURES IN THE LOW TO MID 70S OVERNIGHT.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
EXPECT VFR CONDITIONS TO PERSIST DURING THE TAF PERIOD. ABUNDANT
LOW LEVEL MOISTURE IN PLACE OVERNIGHT BUT NOT EXPECTING
FOG/STRATUS DUE TO THE 25-30 KNOT LOW-LEVEL JET NOTED ON KCAE VAD
WIND PROFILE...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE.

WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET MIXES DOWN
ASSOCIATED WITH SURFACE HEATING BY 15Z. EXPECT GUSTS AROUND 20
KNOTS THROUGH THE AFTERNOON HOURS. THERE REMAINS A CHANCE FOR
AFTERNOON SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$










000
FXUS62 KCAE 190531
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
131 AM EDT TUE AUG 19 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CONVECTION HAS ENDED FOR THE NIGHT AS THE AIRMASS STABILIZES. STILL
WATCHING A SHORT WAVE CROSSING NORTHEAST ALABAMA THAT IS EXPECTED
TO MOVE INTO WESTERN SC AROUND SUNRISE. WILL FORECAST DRY CONDITIONS
FOR THE REMAINDER OF THE NIGHT. SOME CLOUDINESS AND MIXING SHOULD
HELP HOLD UP TEMPERATURES IN THE LOW TO MID 70S OVERNIGHT.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
EXPECT VFR CONDITIONS TO PERSIST DURING THE TAF PERIOD. ABUNDANT
LOW LEVEL MOISTURE IN PLACE OVERNIGHT BUT NOT EXPECTING
FOG/STRATUS DUE TO THE 25-30 KNOT LOW-LEVEL JET NOTED ON KCAE VAD
WIND PROFILE...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE.

WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET MIXES DOWN
ASSOCIATED WITH SURFACE HEATING BY 15Z. EXPECT GUSTS AROUND 20
KNOTS THROUGH THE AFTERNOON HOURS. THERE REMAINS A CHANCE FOR
AFTERNOON SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$










000
FXUS62 KFFC 190516 AAC
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
116 AM EDT TUE AUG 19 2014

.PREV DISCUSSION... /ISSUED 936 PM EDT MON AUG 18 2014/

UPDATE...

HAVE MADE SEVERAL CHANGES TO POPS THROUGH THE EVENING TO ACCOUNT
FOR TRENDS. MOST CONVECTION IS DYING OFF NOW...WITH ONLY LIGHT
RAIN REMAINING...BUT THE LEFTOVER MISSISSIPPI VALLEY MCV IS
WORKING ITS WAY ACROSS NORTHERN ALABAMA AT AFD TIME AND SHOULD
PUSH INTO NORTH GEORGIA IN THE NEXT FEW HOURS. AGAIN HAVE TRIED TO
ADJUST POPS TO ACCOUNT FOR THIS. AIRMASS IS PRETTY STABLE BEHIND
CONVECTION THIS EVENING SO THINK SEVERE POTENTIAL WITH ANY MCV
CONVECTION WOULD BE PRETTY LOW...HEAVY RAIN WOULD BE THE MORE
SIGNIFICANT THREAT.

UPDATED PRODUCTS OUT SHORTLY.

TDP

PREV DISCUSSION... /ISSUED 750 PM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

&&

.AVIATION...
06Z UPDATE...
POTENTIAL FOR INCREASING LIFR-MVFR CEILINGS ACROSS THE TAF SITES
WITH SOME MVFR VSBYS DUE TO FOG. IMPROVEMENT EXPECTED TO VFR DURING
THE LATER MORNING. POTENTIAL FOR SHOWERS AND THUNDERSTORMS ALMOST
ANY TIME TODAY. SURFACE WINDS LIGHT WSW INCREASING TO MAINLY WEST
AROUND 10 KTS WITH SOME GUSTS AROUND 20 KTS.

//ATL CONFIDENCE...06Z UPDATE...
LOW CONFIDENCE ON CEILINGS/VSBYS AND IMPACTS OF THUNDERSTORMS TODAY.
HIGH CONFIDENCE ON WINDS.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          91  72  97  72 /  40  30  10   5
ATLANTA         88  73  94  75 /  40  30  10   5
BLAIRSVILLE     84  67  90  68 /  40  30  20  10
CARTERSVILLE    89  71  94  71 /  40  30  10   5
COLUMBUS        92  73  96  75 /  40  30  10   5
GAINESVILLE     89  71  94  73 /  40  30  10  10
MACON           92  72  97  74 /  40  30  10   5
ROME            89  71  95  71 /  40  30  20  10
PEACHTREE CITY  89  71  94  72 /  40  30  10   5
VIDALIA         95  74  97  76 /  40  30  20   5

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...BDL
LONG TERM....20
AVIATION...BDL





000
FXUS62 KFFC 190516 AAC
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
116 AM EDT TUE AUG 19 2014

.PREV DISCUSSION... /ISSUED 936 PM EDT MON AUG 18 2014/

UPDATE...

HAVE MADE SEVERAL CHANGES TO POPS THROUGH THE EVENING TO ACCOUNT
FOR TRENDS. MOST CONVECTION IS DYING OFF NOW...WITH ONLY LIGHT
RAIN REMAINING...BUT THE LEFTOVER MISSISSIPPI VALLEY MCV IS
WORKING ITS WAY ACROSS NORTHERN ALABAMA AT AFD TIME AND SHOULD
PUSH INTO NORTH GEORGIA IN THE NEXT FEW HOURS. AGAIN HAVE TRIED TO
ADJUST POPS TO ACCOUNT FOR THIS. AIRMASS IS PRETTY STABLE BEHIND
CONVECTION THIS EVENING SO THINK SEVERE POTENTIAL WITH ANY MCV
CONVECTION WOULD BE PRETTY LOW...HEAVY RAIN WOULD BE THE MORE
SIGNIFICANT THREAT.

UPDATED PRODUCTS OUT SHORTLY.

TDP

PREV DISCUSSION... /ISSUED 750 PM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

&&

.AVIATION...
06Z UPDATE...
POTENTIAL FOR INCREASING LIFR-MVFR CEILINGS ACROSS THE TAF SITES
WITH SOME MVFR VSBYS DUE TO FOG. IMPROVEMENT EXPECTED TO VFR DURING
THE LATER MORNING. POTENTIAL FOR SHOWERS AND THUNDERSTORMS ALMOST
ANY TIME TODAY. SURFACE WINDS LIGHT WSW INCREASING TO MAINLY WEST
AROUND 10 KTS WITH SOME GUSTS AROUND 20 KTS.

//ATL CONFIDENCE...06Z UPDATE...
LOW CONFIDENCE ON CEILINGS/VSBYS AND IMPACTS OF THUNDERSTORMS TODAY.
HIGH CONFIDENCE ON WINDS.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          91  72  97  72 /  40  30  10   5
ATLANTA         88  73  94  75 /  40  30  10   5
BLAIRSVILLE     84  67  90  68 /  40  30  20  10
CARTERSVILLE    89  71  94  71 /  40  30  10   5
COLUMBUS        92  73  96  75 /  40  30  10   5
GAINESVILLE     89  71  94  73 /  40  30  10  10
MACON           92  72  97  74 /  40  30  10   5
ROME            89  71  95  71 /  40  30  20  10
PEACHTREE CITY  89  71  94  72 /  40  30  10   5
VIDALIA         95  74  97  76 /  40  30  20   5

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...BDL
LONG TERM....20
AVIATION...BDL






000
FXUS62 KCHS 190504
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
104 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CLOUDS LEFT BEHIND BY EVENING CONVECTION SHOULD THIN WITH TIME
ACROSS SOUTH CAROLINA WITH MOSTLY CLEAR TO PARTLY CLOUDY SKIES
AT TIMES IN SE GEORGIA. MINOR ADJUSTMENTS ON THE MIDNIGHT UPDATE
INCLUDING REMOVING ALL POPS.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 06Z WEDNESDAY. SHOWERS/THUNDERSTORMS
ARE EXPECTED TO REDEVELOP THIS AFTERNOON. REDUCED CIGS/VSBYS POSSIBLE
WITHIN ANY THUNDERSTORM THAT DIRECTLY AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
TSTMS OVER THE SOUTH CAROLINA WATERS HAVE MOVED WELL OFFSHORE. THE
SW SYNOPTIC FLOW WAS DISTURBED BY THE PASSAGE OF THE CONVECTION BUT
SHOULD RESUME OVERNIGHT. SW FLOW 10 TO 20 KT...HIGHEST OFFSHORE AND
SEAS 2 TO 4 FT NEAR SHORE AND 3 TO 5 FT FROM THE PILOT BUOYS SEAWARD.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 190504
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
104 AM EDT TUE AUG 19 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CLOUDS LEFT BEHIND BY EVENING CONVECTION SHOULD THIN WITH TIME
ACROSS SOUTH CAROLINA WITH MOSTLY CLEAR TO PARTLY CLOUDY SKIES
AT TIMES IN SE GEORGIA. MINOR ADJUSTMENTS ON THE MIDNIGHT UPDATE
INCLUDING REMOVING ALL POPS.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 06Z WEDNESDAY. SHOWERS/THUNDERSTORMS
ARE EXPECTED TO REDEVELOP THIS AFTERNOON. REDUCED CIGS/VSBYS POSSIBLE
WITHIN ANY THUNDERSTORM THAT DIRECTLY AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
TSTMS OVER THE SOUTH CAROLINA WATERS HAVE MOVED WELL OFFSHORE. THE
SW SYNOPTIC FLOW WAS DISTURBED BY THE PASSAGE OF THE CONVECTION BUT
SHOULD RESUME OVERNIGHT. SW FLOW 10 TO 20 KT...HIGHEST OFFSHORE AND
SEAS 2 TO 4 FT NEAR SHORE AND 3 TO 5 FT FROM THE PILOT BUOYS SEAWARD.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 190255
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1055 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL DECREASE IN
THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS TAPER TO
LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY EVENING
CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
THE SEA BREEZE WILL GIVE WAY TO ANOTHER ROUND OF ELEVATED SW
WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT ISOLATED GUSTS AS HIGH
AS 25 KT CANNOT BE RULED OUT ESPECIALLY WITHIN AMZ350 AND AMZ374.
WINDS WILL THEN VEER TOWARD THE W/SW AND WILL DIMINISH AS THE LAND
BREEZE DEVELOPS LATER TONIGHT. SEAS WILL RANGE FROM 2-4 FT WITHIN
NEARSHORE WATERS TO AS HIGH AS 4-5 FT BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...33
LONG TERM...JRL
AVIATION...ECT
MARINE...33/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 190255
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1055 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL DECREASE IN
THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS TAPER TO
LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY EVENING
CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
THE SEA BREEZE WILL GIVE WAY TO ANOTHER ROUND OF ELEVATED SW
WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT ISOLATED GUSTS AS HIGH
AS 25 KT CANNOT BE RULED OUT ESPECIALLY WITHIN AMZ350 AND AMZ374.
WINDS WILL THEN VEER TOWARD THE W/SW AND WILL DIMINISH AS THE LAND
BREEZE DEVELOPS LATER TONIGHT. SEAS WILL RANGE FROM 2-4 FT WITHIN
NEARSHORE WATERS TO AS HIGH AS 4-5 FT BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...33
LONG TERM...JRL
AVIATION...ECT
MARINE...33/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 190255
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1055 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL DECREASE IN
THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS TAPER TO
LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY EVENING
CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
THE SEA BREEZE WILL GIVE WAY TO ANOTHER ROUND OF ELEVATED SW
WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT ISOLATED GUSTS AS HIGH
AS 25 KT CANNOT BE RULED OUT ESPECIALLY WITHIN AMZ350 AND AMZ374.
WINDS WILL THEN VEER TOWARD THE W/SW AND WILL DIMINISH AS THE LAND
BREEZE DEVELOPS LATER TONIGHT. SEAS WILL RANGE FROM 2-4 FT WITHIN
NEARSHORE WATERS TO AS HIGH AS 4-5 FT BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...33
LONG TERM...JRL
AVIATION...ECT
MARINE...33/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 190255
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1055 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL DECREASE IN
THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS TAPER TO
LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY EVENING
CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
THE SEA BREEZE WILL GIVE WAY TO ANOTHER ROUND OF ELEVATED SW
WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT ISOLATED GUSTS AS HIGH
AS 25 KT CANNOT BE RULED OUT ESPECIALLY WITHIN AMZ350 AND AMZ374.
WINDS WILL THEN VEER TOWARD THE W/SW AND WILL DIMINISH AS THE LAND
BREEZE DEVELOPS LATER TONIGHT. SEAS WILL RANGE FROM 2-4 FT WITHIN
NEARSHORE WATERS TO AS HIGH AS 4-5 FT BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...
SHORT TERM...33
LONG TERM...JRL
AVIATION...ECT
MARINE...33/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCAE 190156
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
956 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /OVERNIGHT/...
SCATTERED CONVECTION ACROSS SC/EASTERN GA CONTINUES TO SLOWLY
DIMINISH DURING THE LATE EVENING HOURS. ATMOSPHERE IS STILL
MODERATELY UNSTABLE BUT WITH LOSS OF DAYTIME HEATING STILL EXPECT
CONVECTION TO CONTINUE TO WEAKEN OVER THE NEXT COUPLE OF HOURS. SOME
CLOUDINESS AND MIXING SHOULD HELP HOLD UP TEMPERATURES OVERNIGHT.
FORECAST LOWS IN THE LOWER TO MIDDLE 70S LOOK REASONABLE.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS TO CONTINUE DURING THE TAF PERIOD.
ISOLATED SHOWERS/THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE
OVERNIGHT. THERE REMAINS ENOUGH MOISTURE OVERNIGHT IN THE MID-
LEVELS TO SUPPORT FEW/SCT CLOUDS. THERE IS ALSO SOME LOW-LEVEL
MOISTURE...BUT AT THIS TIME DO NOT ANTICIPATE MUCH IN THE WAY OF
FOG/STRATUS. THIS IS DUE TO THE MODELS SHOWING A STRONG LOW-LEVEL
JET SETTING UP ACROSS THE REGION...WHICH SHOULD HELP WITH MIXING
OVERNIGHT. IF WINDS GO LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN
ISSUE.

AS FOR TUESDAY...WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND
JET MIXES DOWN TO THE SURFACE. EXPECT GUSTS TO REMAIN THROUGH THE
AFTERNOON HOURS. THERE REMAINS A CHANCE FOR AFTERNOON SHOWERS/STORMS
ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$










000
FXUS62 KCAE 190156
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
956 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /OVERNIGHT/...
SCATTERED CONVECTION ACROSS SC/EASTERN GA CONTINUES TO SLOWLY
DIMINISH DURING THE LATE EVENING HOURS. ATMOSPHERE IS STILL
MODERATELY UNSTABLE BUT WITH LOSS OF DAYTIME HEATING STILL EXPECT
CONVECTION TO CONTINUE TO WEAKEN OVER THE NEXT COUPLE OF HOURS. SOME
CLOUDINESS AND MIXING SHOULD HELP HOLD UP TEMPERATURES OVERNIGHT.
FORECAST LOWS IN THE LOWER TO MIDDLE 70S LOOK REASONABLE.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS TO CONTINUE DURING THE TAF PERIOD.
ISOLATED SHOWERS/THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE
OVERNIGHT. THERE REMAINS ENOUGH MOISTURE OVERNIGHT IN THE MID-
LEVELS TO SUPPORT FEW/SCT CLOUDS. THERE IS ALSO SOME LOW-LEVEL
MOISTURE...BUT AT THIS TIME DO NOT ANTICIPATE MUCH IN THE WAY OF
FOG/STRATUS. THIS IS DUE TO THE MODELS SHOWING A STRONG LOW-LEVEL
JET SETTING UP ACROSS THE REGION...WHICH SHOULD HELP WITH MIXING
OVERNIGHT. IF WINDS GO LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN
ISSUE.

AS FOR TUESDAY...WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND
JET MIXES DOWN TO THE SURFACE. EXPECT GUSTS TO REMAIN THROUGH THE
AFTERNOON HOURS. THERE REMAINS A CHANCE FOR AFTERNOON SHOWERS/STORMS
ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$











000
FXUS62 KFFC 190136 AAB
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
936 PM EDT MON AUG 18 2014

.UPDATE...

HAVE MADE SEVERAL CHANGES TO POPS THROUGH THE EVENING TO ACCOUNT
FOR TRENDS. MOST CONVECTION IS DYING OFF NOW...WITH ONLY LIGHT
RAIN REMAINING...BUT THE LEFTOVER MISSISSIPPI VALLEY MCV IS
WORKING ITS WAY ACROSS NORTHERN ALABAMA AT AFD TIME AND SHOULD
PUSH INTO NORTH GEORGIA IN THE NEXT FEW HOURS. AGAIN HAVE TRIED TO
ADJUST POPS TO ACCOUNT FOR THIS. AIRMASS IS PRETTY STABLE BEHIND
CONVECTION THIS EVENING SO THINK SEVERE POTENTIAL WITH ANY MCV
CONVECTION WOULD BE PRETTY LOW...HEAVY RAIN WOULD BE THE MORE
SIGNIFICANT THREAT.

UPDATED PRODUCTS OUT SHORTLY.

TDP

&&

.PREV DISCUSSION... /ISSUED 750 PM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

AVIATION...
00Z UPDATE...
AREA OF TSRA AFFECTING MOST TAF SITES THIS EVENING...THOUGH SHOULD
SEE A DIMINISHING TREND OVER THE NEXT FEW HOURS. EXPECT TO SEE
MVFR CIGS DEVELOP OVERNIGHT AND CANNOT RULE OUT BRIEF IFR CIGS.
CLEARING TOMORROW MORNING BUT HAVE INCLUDED PROB30 DURING THE
AFTERNOON TO COVER CHANCE OF CONVECTION. WINDS W THROUGH THE
PERIOD GENERALLY BETWEEN 5-10KT THOUGH VRB AND GUSTY IN TSRA THIS
EVENING...AND LOW END GUSTS TUESDAY.

//ATL CONFIDENCE...00Z UPDATE...
HIGH ON CONVECTION TONIGHT...MEDIUM ON TIMING OF CLEARING.
MEDIUM ON EARLY MORNING CIGS...LOW ON POTENTIAL IFR DEVELOPMENT.
HIGH ON ALL OTHER ELEMENTS.

TDP

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          71  91  72  97 /  60  40  30  10
ATLANTA         72  88  73  94 /  60  40  30  10
BLAIRSVILLE     66  84  67  90 /  60  40  30  20
CARTERSVILLE    70  89  71  94 /  60  40  30  10
COLUMBUS        72  92  73  96 /  60  40  30  10
GAINESVILLE     70  89  71  94 /  60  40  30  10
MACON           72  92  72  97 /  60  40  30  10
ROME            70  89  71  95 /  60  40  30  20
PEACHTREE CITY  71  89  71  94 /  60  40  30  10
VIDALIA         74  95  74  97 /  40  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$




000
FXUS62 KFFC 190136 AAB
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
936 PM EDT MON AUG 18 2014

.UPDATE...

HAVE MADE SEVERAL CHANGES TO POPS THROUGH THE EVENING TO ACCOUNT
FOR TRENDS. MOST CONVECTION IS DYING OFF NOW...WITH ONLY LIGHT
RAIN REMAINING...BUT THE LEFTOVER MISSISSIPPI VALLEY MCV IS
WORKING ITS WAY ACROSS NORTHERN ALABAMA AT AFD TIME AND SHOULD
PUSH INTO NORTH GEORGIA IN THE NEXT FEW HOURS. AGAIN HAVE TRIED TO
ADJUST POPS TO ACCOUNT FOR THIS. AIRMASS IS PRETTY STABLE BEHIND
CONVECTION THIS EVENING SO THINK SEVERE POTENTIAL WITH ANY MCV
CONVECTION WOULD BE PRETTY LOW...HEAVY RAIN WOULD BE THE MORE
SIGNIFICANT THREAT.

UPDATED PRODUCTS OUT SHORTLY.

TDP

&&

.PREV DISCUSSION... /ISSUED 750 PM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

AVIATION...
00Z UPDATE...
AREA OF TSRA AFFECTING MOST TAF SITES THIS EVENING...THOUGH SHOULD
SEE A DIMINISHING TREND OVER THE NEXT FEW HOURS. EXPECT TO SEE
MVFR CIGS DEVELOP OVERNIGHT AND CANNOT RULE OUT BRIEF IFR CIGS.
CLEARING TOMORROW MORNING BUT HAVE INCLUDED PROB30 DURING THE
AFTERNOON TO COVER CHANCE OF CONVECTION. WINDS W THROUGH THE
PERIOD GENERALLY BETWEEN 5-10KT THOUGH VRB AND GUSTY IN TSRA THIS
EVENING...AND LOW END GUSTS TUESDAY.

//ATL CONFIDENCE...00Z UPDATE...
HIGH ON CONVECTION TONIGHT...MEDIUM ON TIMING OF CLEARING.
MEDIUM ON EARLY MORNING CIGS...LOW ON POTENTIAL IFR DEVELOPMENT.
HIGH ON ALL OTHER ELEMENTS.

TDP

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          71  91  72  97 /  60  40  30  10
ATLANTA         72  88  73  94 /  60  40  30  10
BLAIRSVILLE     66  84  67  90 /  60  40  30  20
CARTERSVILLE    70  89  71  94 /  60  40  30  10
COLUMBUS        72  92  73  96 /  60  40  30  10
GAINESVILLE     70  89  71  94 /  60  40  30  10
MACON           72  92  72  97 /  60  40  30  10
ROME            70  89  71  95 /  60  40  30  20
PEACHTREE CITY  71  89  71  94 /  60  40  30  10
VIDALIA         74  95  74  97 /  40  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$




000
FXUS62 KFFC 190136 AAB
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
936 PM EDT MON AUG 18 2014

.UPDATE...

HAVE MADE SEVERAL CHANGES TO POPS THROUGH THE EVENING TO ACCOUNT
FOR TRENDS. MOST CONVECTION IS DYING OFF NOW...WITH ONLY LIGHT
RAIN REMAINING...BUT THE LEFTOVER MISSISSIPPI VALLEY MCV IS
WORKING ITS WAY ACROSS NORTHERN ALABAMA AT AFD TIME AND SHOULD
PUSH INTO NORTH GEORGIA IN THE NEXT FEW HOURS. AGAIN HAVE TRIED TO
ADJUST POPS TO ACCOUNT FOR THIS. AIRMASS IS PRETTY STABLE BEHIND
CONVECTION THIS EVENING SO THINK SEVERE POTENTIAL WITH ANY MCV
CONVECTION WOULD BE PRETTY LOW...HEAVY RAIN WOULD BE THE MORE
SIGNIFICANT THREAT.

UPDATED PRODUCTS OUT SHORTLY.

TDP

&&

.PREV DISCUSSION... /ISSUED 750 PM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

AVIATION...
00Z UPDATE...
AREA OF TSRA AFFECTING MOST TAF SITES THIS EVENING...THOUGH SHOULD
SEE A DIMINISHING TREND OVER THE NEXT FEW HOURS. EXPECT TO SEE
MVFR CIGS DEVELOP OVERNIGHT AND CANNOT RULE OUT BRIEF IFR CIGS.
CLEARING TOMORROW MORNING BUT HAVE INCLUDED PROB30 DURING THE
AFTERNOON TO COVER CHANCE OF CONVECTION. WINDS W THROUGH THE
PERIOD GENERALLY BETWEEN 5-10KT THOUGH VRB AND GUSTY IN TSRA THIS
EVENING...AND LOW END GUSTS TUESDAY.

//ATL CONFIDENCE...00Z UPDATE...
HIGH ON CONVECTION TONIGHT...MEDIUM ON TIMING OF CLEARING.
MEDIUM ON EARLY MORNING CIGS...LOW ON POTENTIAL IFR DEVELOPMENT.
HIGH ON ALL OTHER ELEMENTS.

TDP

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          71  91  72  97 /  60  40  30  10
ATLANTA         72  88  73  94 /  60  40  30  10
BLAIRSVILLE     66  84  67  90 /  60  40  30  20
CARTERSVILLE    70  89  71  94 /  60  40  30  10
COLUMBUS        72  92  73  96 /  60  40  30  10
GAINESVILLE     70  89  71  94 /  60  40  30  10
MACON           72  92  72  97 /  60  40  30  10
ROME            70  89  71  95 /  60  40  30  20
PEACHTREE CITY  71  89  71  94 /  60  40  30  10
VIDALIA         74  95  74  97 /  40  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$




000
FXUS62 KFFC 190136 AAB
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
936 PM EDT MON AUG 18 2014

.UPDATE...

HAVE MADE SEVERAL CHANGES TO POPS THROUGH THE EVENING TO ACCOUNT
FOR TRENDS. MOST CONVECTION IS DYING OFF NOW...WITH ONLY LIGHT
RAIN REMAINING...BUT THE LEFTOVER MISSISSIPPI VALLEY MCV IS
WORKING ITS WAY ACROSS NORTHERN ALABAMA AT AFD TIME AND SHOULD
PUSH INTO NORTH GEORGIA IN THE NEXT FEW HOURS. AGAIN HAVE TRIED TO
ADJUST POPS TO ACCOUNT FOR THIS. AIRMASS IS PRETTY STABLE BEHIND
CONVECTION THIS EVENING SO THINK SEVERE POTENTIAL WITH ANY MCV
CONVECTION WOULD BE PRETTY LOW...HEAVY RAIN WOULD BE THE MORE
SIGNIFICANT THREAT.

UPDATED PRODUCTS OUT SHORTLY.

TDP

&&

.PREV DISCUSSION... /ISSUED 750 PM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

AVIATION...
00Z UPDATE...
AREA OF TSRA AFFECTING MOST TAF SITES THIS EVENING...THOUGH SHOULD
SEE A DIMINISHING TREND OVER THE NEXT FEW HOURS. EXPECT TO SEE
MVFR CIGS DEVELOP OVERNIGHT AND CANNOT RULE OUT BRIEF IFR CIGS.
CLEARING TOMORROW MORNING BUT HAVE INCLUDED PROB30 DURING THE
AFTERNOON TO COVER CHANCE OF CONVECTION. WINDS W THROUGH THE
PERIOD GENERALLY BETWEEN 5-10KT THOUGH VRB AND GUSTY IN TSRA THIS
EVENING...AND LOW END GUSTS TUESDAY.

//ATL CONFIDENCE...00Z UPDATE...
HIGH ON CONVECTION TONIGHT...MEDIUM ON TIMING OF CLEARING.
MEDIUM ON EARLY MORNING CIGS...LOW ON POTENTIAL IFR DEVELOPMENT.
HIGH ON ALL OTHER ELEMENTS.

TDP

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          71  91  72  97 /  60  40  30  10
ATLANTA         72  88  73  94 /  60  40  30  10
BLAIRSVILLE     66  84  67  90 /  60  40  30  20
CARTERSVILLE    70  89  71  94 /  60  40  30  10
COLUMBUS        72  92  73  96 /  60  40  30  10
GAINESVILLE     70  89  71  94 /  60  40  30  10
MACON           72  92  72  97 /  60  40  30  10
ROME            70  89  71  95 /  60  40  30  20
PEACHTREE CITY  71  89  71  94 /  60  40  30  10
VIDALIA         74  95  74  97 /  40  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$




000
FXUS62 KCHS 190028
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
730 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...33/SPR
CLIMATE...
EQUIPMENT...










000
FXUS62 KCHS 190028
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
730 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...33/SPR
CLIMATE...
EQUIPMENT...










000
FXUS62 KCHS 190028
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
730 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...33/SPR
CLIMATE...
EQUIPMENT...










000
FXUS62 KCHS 190028
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
730 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2012

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...33/SPR
CLIMATE...
EQUIPMENT...










000
FXUS62 KFFC 182350 AAA
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
750 PM EDT MON AUG 18 2014

.PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

&&

.AVIATION...
00Z UPDATE...
AREA OF TSRA AFFECTING MOST TAF SITES THIS EVENING...THOUGH SHOULD
SEE A DIMINISHING TREND OVER THE NEXT FEW HOURS. EXPECT TO SEE
MVFR CIGS DEVELOP OVERNIGHT AND CANNOT RULE OUT BRIEF IFR CIGS.
CLEARING TOMORROW MORNING BUT HAVE INCLUDED PROB30 DURING THE
AFTERNOON TO COVER CHANCE OF CONVECTION. WINDS W THROUGH THE
PERIOD GENERALLY BETWEEN 5-10KT THOUGH VRB AND GUSTY IN TSRA THIS
EVENING...AND LOW END GUSTS TUESDAY.

//ATL CONFIDENCE...00Z UPDATE...
HIGH ON CONVECTION TONIGHT...MEDIUM ON TIMING OF CLEARING.
MEDIUM ON EARLY MORNING CIGS...LOW ON POTENTIAL IFR DEVELOPMENT.
HIGH ON ALL OTHER ELEMENTS.

TDP

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          71  91  72  97 /  50  40  30  10
ATLANTA         72  88  73  94 /  60  40  30  10
BLAIRSVILLE     67  84  67  90 /  60  40  30  20
CARTERSVILLE    70  89  71  94 /  60  40  30  10
COLUMBUS        74  92  73  96 /  60  40  30  10
GAINESVILLE     71  89  71  94 /  60  40  30  10
MACON           73  92  72  97 /  60  40  30  10
ROME            71  89  71  95 /  60  40  30  20
PEACHTREE CITY  71  89  71  94 /  60  40  30  10
VIDALIA         75  95  74  97 /  40  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$




000
FXUS62 KFFC 182350 AAA
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
750 PM EDT MON AUG 18 2014

.PREV DISCUSSION... /ISSUED 320 PM EDT MON AUG 18 2014/

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

&&

.AVIATION...
00Z UPDATE...
AREA OF TSRA AFFECTING MOST TAF SITES THIS EVENING...THOUGH SHOULD
SEE A DIMINISHING TREND OVER THE NEXT FEW HOURS. EXPECT TO SEE
MVFR CIGS DEVELOP OVERNIGHT AND CANNOT RULE OUT BRIEF IFR CIGS.
CLEARING TOMORROW MORNING BUT HAVE INCLUDED PROB30 DURING THE
AFTERNOON TO COVER CHANCE OF CONVECTION. WINDS W THROUGH THE
PERIOD GENERALLY BETWEEN 5-10KT THOUGH VRB AND GUSTY IN TSRA THIS
EVENING...AND LOW END GUSTS TUESDAY.

//ATL CONFIDENCE...00Z UPDATE...
HIGH ON CONVECTION TONIGHT...MEDIUM ON TIMING OF CLEARING.
MEDIUM ON EARLY MORNING CIGS...LOW ON POTENTIAL IFR DEVELOPMENT.
HIGH ON ALL OTHER ELEMENTS.

TDP

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          71  91  72  97 /  50  40  30  10
ATLANTA         72  88  73  94 /  60  40  30  10
BLAIRSVILLE     67  84  67  90 /  60  40  30  20
CARTERSVILLE    70  89  71  94 /  60  40  30  10
COLUMBUS        74  92  73  96 /  60  40  30  10
GAINESVILLE     71  89  71  94 /  60  40  30  10
MACON           73  92  72  97 /  60  40  30  10
ROME            71  89  71  95 /  60  40  30  20
PEACHTREE CITY  71  89  71  94 /  60  40  30  10
VIDALIA         75  95  74  97 /  40  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$





000
FXUS62 KCAE 182341
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
741 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /TONIGHT/...
WIDELY SCATTERED/SCATTERED CONVECTION CONTINUES OVER THE AREA
EARLY THIS EVENING AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. LATEST
ATMOSPHERE IS STILL RATHER UNSTABLE SO WILL CONTINUE MENTION OF
LOW CHANCE POPS UNTIL AROUND MIDNIGHT. THE CONTINUED MODERATE
INSTABILITY SUPPORTS A POSSIBILITY OF DAMAGING WIND WITH A FEW OF
THE THUNDERSTORMS. SOME CLOUDINESS AND MIXING SHOULD HELP HOLD UP
TEMPERATURES. THE GUIDANCE WAS CLOSE WITH LOWS MAINLY IN THE
MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS TO CONTINUE DURING THE TAF PERIOD. SOME
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE REGION
THROUGH 03Z...BUT CONFIDENCE NOT HIGH ENOUGH TO PUT IN TAFS AT THIS
TIME.  THERE REMAINS ENOUGH MOISTURE OVERNIGHT IN THE MID-LEVELS TO
SUPPORT FEW/SCT CLOUDS.  THERE IS ALSO SOME LOW-LEVEL MOISTURE...BUT
AT THIS TIME DO NOT ANTICIPATE MUCH IN THE WAY OF FOG/STRATUS.  THIS
IS DUE TO THE MODELS SHOWING A STRONG LOW-LEVEL JET SETTING UP ACROSS
THE REGION...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE. AS FOR
TUESDAY...WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET
MIXES DOWN TO THE SURFACE. EXPECT GUSTS TO REMAIN THROUGH THE
AFTERNOON HOURS. THERE REMAINS A CHANCE FOR AFTERNOON
SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$














000
FXUS62 KCAE 182341
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
741 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /TONIGHT/...
WIDELY SCATTERED/SCATTERED CONVECTION CONTINUES OVER THE AREA
EARLY THIS EVENING AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. LATEST
ATMOSPHERE IS STILL RATHER UNSTABLE SO WILL CONTINUE MENTION OF
LOW CHANCE POPS UNTIL AROUND MIDNIGHT. THE CONTINUED MODERATE
INSTABILITY SUPPORTS A POSSIBILITY OF DAMAGING WIND WITH A FEW OF
THE THUNDERSTORMS. SOME CLOUDINESS AND MIXING SHOULD HELP HOLD UP
TEMPERATURES. THE GUIDANCE WAS CLOSE WITH LOWS MAINLY IN THE
MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS TO CONTINUE DURING THE TAF PERIOD. SOME
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE REGION
THROUGH 03Z...BUT CONFIDENCE NOT HIGH ENOUGH TO PUT IN TAFS AT THIS
TIME.  THERE REMAINS ENOUGH MOISTURE OVERNIGHT IN THE MID-LEVELS TO
SUPPORT FEW/SCT CLOUDS.  THERE IS ALSO SOME LOW-LEVEL MOISTURE...BUT
AT THIS TIME DO NOT ANTICIPATE MUCH IN THE WAY OF FOG/STRATUS.  THIS
IS DUE TO THE MODELS SHOWING A STRONG LOW-LEVEL JET SETTING UP ACROSS
THE REGION...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE. AS FOR
TUESDAY...WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET
MIXES DOWN TO THE SURFACE. EXPECT GUSTS TO REMAIN THROUGH THE
AFTERNOON HOURS. THERE REMAINS A CHANCE FOR AFTERNOON
SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$














000
FXUS62 KCAE 182341
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
741 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /TONIGHT/...
WIDELY SCATTERED/SCATTERED CONVECTION CONTINUES OVER THE AREA
EARLY THIS EVENING AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. LATEST
ATMOSPHERE IS STILL RATHER UNSTABLE SO WILL CONTINUE MENTION OF
LOW CHANCE POPS UNTIL AROUND MIDNIGHT. THE CONTINUED MODERATE
INSTABILITY SUPPORTS A POSSIBILITY OF DAMAGING WIND WITH A FEW OF
THE THUNDERSTORMS. SOME CLOUDINESS AND MIXING SHOULD HELP HOLD UP
TEMPERATURES. THE GUIDANCE WAS CLOSE WITH LOWS MAINLY IN THE
MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS TO CONTINUE DURING THE TAF PERIOD. SOME
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE REGION
THROUGH 03Z...BUT CONFIDENCE NOT HIGH ENOUGH TO PUT IN TAFS AT THIS
TIME.  THERE REMAINS ENOUGH MOISTURE OVERNIGHT IN THE MID-LEVELS TO
SUPPORT FEW/SCT CLOUDS.  THERE IS ALSO SOME LOW-LEVEL MOISTURE...BUT
AT THIS TIME DO NOT ANTICIPATE MUCH IN THE WAY OF FOG/STRATUS.  THIS
IS DUE TO THE MODELS SHOWING A STRONG LOW-LEVEL JET SETTING UP ACROSS
THE REGION...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE. AS FOR
TUESDAY...WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET
MIXES DOWN TO THE SURFACE. EXPECT GUSTS TO REMAIN THROUGH THE
AFTERNOON HOURS. THERE REMAINS A CHANCE FOR AFTERNOON
SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$














000
FXUS62 KCAE 182341
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
741 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /TONIGHT/...
WIDELY SCATTERED/SCATTERED CONVECTION CONTINUES OVER THE AREA
EARLY THIS EVENING AHEAD OF A MID-LEVEL SHORTWAVE TROUGH. LATEST
ATMOSPHERE IS STILL RATHER UNSTABLE SO WILL CONTINUE MENTION OF
LOW CHANCE POPS UNTIL AROUND MIDNIGHT. THE CONTINUED MODERATE
INSTABILITY SUPPORTS A POSSIBILITY OF DAMAGING WIND WITH A FEW OF
THE THUNDERSTORMS. SOME CLOUDINESS AND MIXING SHOULD HELP HOLD UP
TEMPERATURES. THE GUIDANCE WAS CLOSE WITH LOWS MAINLY IN THE
MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS TO CONTINUE DURING THE TAF PERIOD. SOME
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE REGION
THROUGH 03Z...BUT CONFIDENCE NOT HIGH ENOUGH TO PUT IN TAFS AT THIS
TIME.  THERE REMAINS ENOUGH MOISTURE OVERNIGHT IN THE MID-LEVELS TO
SUPPORT FEW/SCT CLOUDS.  THERE IS ALSO SOME LOW-LEVEL MOISTURE...BUT
AT THIS TIME DO NOT ANTICIPATE MUCH IN THE WAY OF FOG/STRATUS.  THIS
IS DUE TO THE MODELS SHOWING A STRONG LOW-LEVEL JET SETTING UP ACROSS
THE REGION...WHICH SHOULD HELP WITH MIXING OVERNIGHT. IF WINDS GO
LIGHT ENOUGH OVERNIGHT...LLWS MAY BECOME AN ISSUE. AS FOR
TUESDAY...WINDS SHOULD STRENGTHEN AS MIXING INCREASES AND JET
MIXES DOWN TO THE SURFACE. EXPECT GUSTS TO REMAIN THROUGH THE
AFTERNOON HOURS. THERE REMAINS A CHANCE FOR AFTERNOON
SHOWERS/STORMS ACROSS THE REGION TUESDAY.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. ISOLATED AFTERNOON
AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$














000
FXUS62 KCHS 182330
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
730 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2013

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...33/SPR
CLIMATE...
EQUIPMENT...






000
FXUS62 KCHS 182330
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
730 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 00Z TUESDAY. ONGOING THUNDERSTORM
ACTIVITY COULD IMPACT THE TERMINALS EARLY IN THE PERIOD...BEFORE
DIMINISHING WITH LOSS OF INSOLATION. WILL INCLUDE VCTS TO ADDRESS
THIS AND AMEND IF NEEDED BASED ON LATEST RADAR TRENDS.
SHOWERS/THUNDERSTORMS ARE EXPECTED TO REDEVELOP TUESDAY AFTERNOON.
REDUCED CIGS/VSBYS POSSIBLE WITHIN ANY THUNDERSTORM THAT DIRECTLY
AFFECTS THE TERMINALS.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2013

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...
MARINE...33/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 182146
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
546 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS INTO THIS EVENING. WILL
AMEND AS DICTATED BY NEAR TERM CONVECTIVE TRENDS. THUNDERSTORMS
WILL REDEVELOP TUESDAY...BUT MOST LIKELY NOT BEFORE 18Z.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2013

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...33/SPR
MARINE...33/SPR
CLIMATE...33
EQUIPMENT...






000
FXUS62 KCHS 182146
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
546 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY MONDAY EVENING...ADJUSTED POPS BASED ON RECENT/EXPECTED NEAR
TERM TRENDS.

INTO THIS EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED WITHIN
DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL OF
HIGH THETA-E AIR WILL CONTINUE TO SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS INTO THIS EVENING. WILL
AMEND AS DICTATED BY NEAR TERM CONVECTIVE TRENDS. THUNDERSTORMS
WILL REDEVELOP TUESDAY...BUT MOST LIKELY NOT BEFORE 18Z.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2013

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...33/SPR
MARINE...33/SPR
CLIMATE...33
EQUIPMENT...







000
FXUS62 KCAE 182052
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
452 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
LATE THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-
LEVEL SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE
INTO THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. LATEST
RADAR LOOP SHOWING CONVECTIVE COVERAGE HAS DIMINISHED CONSIDERABLY
OVER THE PAST HOUR OR SO BUT ATMOSPHERE IS STILL RATHER UNSTABLE
SO WILL CONTINUE MENTION OF LOW CHANCE POPS. THE STRONG
INSTABILITY SUPPORTS A POSSIBILITY OF DAMAGING WIND WITH A FEW OF
THE THUNDERSTORMS. EXPECT LATE AFTERNOON TEMPERATURES WILL PEAK
IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /21Z MONDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. EARLY AFTERNOON SURFACE-
BASED LI/S WERE -7 TO -8. THE STRONG INSTABILITY SUPPORTS STRONG
WINDS NEAR ANY THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 182052
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
452 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
LATE THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-
LEVEL SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE
INTO THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. LATEST
RADAR LOOP SHOWING CONVECTIVE COVERAGE HAS DIMINISHED CONSIDERABLY
OVER THE PAST HOUR OR SO BUT ATMOSPHERE IS STILL RATHER UNSTABLE
SO WILL CONTINUE MENTION OF LOW CHANCE POPS. THE STRONG
INSTABILITY SUPPORTS A POSSIBILITY OF DAMAGING WIND WITH A FEW OF
THE THUNDERSTORMS. EXPECT LATE AFTERNOON TEMPERATURES WILL PEAK
IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /21Z MONDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. EARLY AFTERNOON SURFACE-
BASED LI/S WERE -7 TO -8. THE STRONG INSTABILITY SUPPORTS STRONG
WINDS NEAR ANY THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCHS 182015
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
415 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THROUGH EARLY EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED
WITHIN DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL
OF ELEVATED THETA-E AIR WILL CONTINUE TO SUPPORT SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH. CAPPED POPS AT 35-50 PERCENT THROUGH EARLY EVENING...BUT
LOCAL ADJUSTMENTS WILL LIKELY BE REQUIRED WITHIN SUBSEQUENT NEAR
TERM FORECAST UPDATES.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.


&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON.
CONFIDENCE IS INCREASING FOR DIRECT IMPACTS AT KCHS BETWEEN 21Z
AND 24Z...THUS ADDED AN APPROPRIATE TEMPO GROUP. AT KSAV...THE
POTENTIAL FOR DIRECT IMPACTS REMAINS UNCLEAR....THUS MAINTAINED
A PERIOD OF CB/VCTS INTO EARLY EVENING. WILL AMEND AS DICTATED BY
NEAR TERM CONVECTIVE TRENDS. THUNDERSTORMS WILL REDEVELOP
TUESDAY...BUT MOST LIKELY NOT BEFORE 18Z.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2013

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...33/SPR
MARINE...33/SPR
CLIMATE...
EQUIPMENT...







000
FXUS62 KCHS 182015
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
415 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THROUGH EARLY EVENING...MULTIPLE MESOSCALE BOUNDARIES EMBEDDED
WITHIN DEEP LAYER WESTERLY FLOW AND A PERSISTENT LOW-LEVEL POOL
OF ELEVATED THETA-E AIR WILL CONTINUE TO SUPPORT SCATTERED
THUNDERSTORMS WHICH WILL GENERALLY MOVE TOWARD THE EAST AT 15-20
MPH. CAPPED POPS AT 35-50 PERCENT THROUGH EARLY EVENING...BUT
LOCAL ADJUSTMENTS WILL LIKELY BE REQUIRED WITHIN SUBSEQUENT NEAR
TERM FORECAST UPDATES.

850-500 MB WINDS 20-25 KT...MLCAPES 2500-3500 J/KG AND DCAPES
EXCEEDING 1000 J/KG SUGGEST THAT MULTICELL THUNDERSTORMS COULD
PRODUCE ISOLATED/DAMAGING WIND GUSTS. MAINTAINED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS WITHIN THE HAZARDOUS WEATHER
OUTLOOK.

AFTER DARK...DIURNAL STABILIZATION WILL TRANSLATE TO A GRADUAL
DECREASE IN THUNDERSTORMS COVERAGE/INTENSITY. AFTER MIDNIGHT...POPS
TAPER TO LESS THAN 15 PERCENT ALL AREAS. CLOUDS LEFT BEHIND BY
EVENING CONVECTION SHOULD THIN WITH TIME.

LOW TEMPS BY DAYBREAK WILL AVERAGE IN THE MID 70S MOST AREAS...
CLOSE TO 80F AT THE COAST AND PERHAPS ISOLATED LOWER 70S WHERE
RAIN FALLS FAR INLAND.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
TUESDAY...THE LARGE SCALE PATTERN SHOWS A SUB-TROPICAL RIDGE ALIGNED
EAST-WEST ACROSS THE SW ATLANTIC...FLORIDA AND INTO THE GULF OF
MEXICO. WE/RE SITUATED ON THE NORTHERN SIDE OF THIS FEATURE WITHIN A
FAIRLY ZONAL FLOW ALOFT. WHILE WE STILL DO HAVE SOME CAP IN PLACE
DURING THE MORNING...A FAIRLY WELL PRONOUNCED SHORT WAVE...LOCATED
IN THE WESTERN TN VALLEY THIS EVENING WILL ARRIVE DURING THE
AFTERNOON. IT/LL TAP INTO CONSIDERABLE PWATS GREATER THAN 2 INCHES
AND A MOISTURE PROFILE THAT EXTENDS THROUGH MUCH OF THE TROPOSPHERE.
CONVECTION WILL START DEVELOP ALONG THE RESULTANT SEA BREEZE DURING
THE EARLY AND MID AFTERNOON AS WE HIT OUR CONVECTIVE TEMPS. BUT
ADDITIONAL ACTIVITY WILL TRIGGER JUST UPSTREAM IN RESPONSE TO
DIFFERENTIAL HEATING BOUNDARIES AND DUE TO THE PROXIMITY TO THE
INLAND SURFACE TROUGH. SOME ORGANIZATION OF STORMS WILL LIKELY OCCUR
IN RESPONSE TO THE APPROACHING SHORT WAVE...WITH THE GREATEST
COVERAGE TO OCCUR ACROSS OUR CHARLESTON QUAD-COUNTY WHERE 50 POPS
HAVE BEEN INTRODUCED. FURTHER SOUTH/SW WE HAVE ALSO SHOWN CHANCE
POPS...BUT MAINLY IN THE 30-40 PERCENTILE. THERMODYNAMICS AREN/T
OVERLY IMPRESSIVE...BUT EVEN SO MLCAPES 2500-3500 J/KG AND DCAPES
AROUND 1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED AND BRIEF WET
MICROBURSTS.

IT/LL BE ANOTHER HOT AND HUMID DAY WITH 850 TEMPS RISING TO NEAR
19-20C AIDED BY DOWNSLOPE FETCH OFF THE APPALACHIANS WITHIN A DEEP
WESTERLY FLOW. BUT ACTUAL MAX TEMPS WILL BE DETERMINED BY THE ONSET
OF SHOWERS/T-STORMS AND THE THICKER/WIDESPREAD CLOUD COVER. FOR NOW
WE HAVE PLAYED A MORE CONSERVATIVE MID-UPPER 90S...WITH EVEN 90 OR
LOWER 90S AT THE COAST PRIOR TO THE SEA BREEZE FORMATION. DEW POINTS
WON/T BE ABLE TO MIX OUT MUCH WITH PLENTIFUL MOISTURE...AND WHEN
COMBINED WITH THESE TEMPS WILL SUPPORT A MAX HEAT INDEX OF
103-108...OR A LITTLE SHY OF THE HEAT ADVISORY CRITERIA. A FEW
COMMUNITIES NEAR THE COAST COULD BRIEFLY HIT A HEAT INDEX OF 110
DEGREES WITH POOLING OF DEW POINTS NEAR THE PASSAGE OF THE SEA
BREEZE. BUT THIS WOULD BE A SHORT-LIVED OCCURRENCE AND ENCOMPASS TOO
SMALL OF AN AREA TO REQUIRE ANY HEAT ADVISORY.

WEDNESDAY THROUGH THURSDAY...THE PATTERN ALOFT WILL AMPLIFY THROUGH
THE PERIOD AS A THE MID/UPPER LOW OVER THE GREAT LAKES WEDNESDAY
WILL HEAD TOWARD THE MASON-DIXON LINE THURSDAY. SIMULTANEOUSLY THE
SUB-TROPICAL ANTICYCLONE OVER THE GULF WILL EXPAND NORTHWARD. RISING
MID LEVEL HEIGHTS...850 MB TEMPS CLIMBING ANOTHER DEGREE OR SO AND
AN EXPANSION OF THE LOW LEVEL THICKNESS IMPLIES THAT THE HEAT WILL
BE CRANKED UP.

WITH NVA ACROSS THE REGION WEDNESDAY THERE IS LITTLE CHANCE OF
CONVECTION...AND AT BEST ONLY HINTS OF A WEAK SHORT WAVE WITHIN THE
NW FLOW THURSDAY. FOR NOW WE/LL GO WITH ONLY SLIGHT CHANCE POPS EACH
AFTERNOON/EVENING WITH THE WARM MID LEVELS AND ASSOCIATED SUBSIDENCE
CAP...WITH THE OPTION TO INCREASE POPS ON THURSDAY SHOULD A BETTER
DEFINED FEATURE INDEED ARRIVE.

GIVEN THE LIMITATION OF SHOWERS/T-STORMS WE LOOK FOR TEMPS TO CLIMB
ANOTHER DEGREE OR TWO EACH DAY...PERHAPS MAKING A RUN FOR RECORDS
AND MAYBE EVEN THE CENTURY MARK IN A COUPLE OF SPOTS /SEE THE
CLIMATE SECTION BELOW MORE ADDITIONAL INFORMATION/. THERE WILL BE
SOME MIXING OUT OF AFTERNOON DEW POINTS WITH THE DEEP OFFSHORE
TRAJECTORIES...BUT WE CERTAINLY COULD BE CLOSE TO OUR HEAT INDEX
CRITERIA OF 110 DEGREES BOTH AFTERNOONS...ESPECIALLY THURSDAY.


&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON.
CONFIDENCE IS INCREASING FOR DIRECT IMPACTS AT KCHS BETWEEN 21Z
AND 24Z...THUS ADDED AN APPROPRIATE TEMPO GROUP. AT KSAV...THE
POTENTIAL FOR DIRECT IMPACTS REMAINS UNCLEAR....THUS MAINTAINED
A PERIOD OF CB/VCTS INTO EARLY EVENING. WILL AMEND AS DICTATED BY
NEAR TERM CONVECTIVE TRENDS. THUNDERSTORMS WILL REDEVELOP
TUESDAY...BUT MOST LIKELY NOT BEFORE 18Z.

EXTENDED AVIATION OUTLOOK...DECENT SHOT AT FLIGHT RESTRICTIONS IN
SCATTERED SHRA/TSRA TUESDAY AFTERNOON/EVENING AS A DISTURBANCE MOVES
BY IN THE MID LEVELS OF THE ATMOSPHERE. THEN VFR MUCH OF THE TIME
THROUGH FRIDAY...WITH THE NEXT GOOD CHANCE OF SUB-VFR WEATHER TO
OCCUR SATURDAY AS A COLD FRONT MOVES IN WITH SCATTERED SHRA/TSRA.

&&

.MARINE...
ANY THUNDERSTORMS WHICH EMERGE FROM LAND COULD PRODUCE STRONG WIND
GUSTS THROUGH THIS EVENING.

OUTSIDE ANY THUNDERSTORMS...THE SEA BREEZE WILL GIVE WAY TO ANOTHER
ROUND OF ELEVATED SW WINDS TONIGHT. CAPPED WINDS AT 20 KT...BUT
ISOLATED GUSTS AS HIGH AS 25 KT CANNOT BE RULED OUT ESPECIALLY
WITHIN AMZ350 AND AMZ374. WINDS WILL THEN VEER TOWARD THE W/SW AND
WILL DIMINISH AS THE LAND BREEZE DEVELOPS LATER TONIGHT. SEAS WILL
RANGE FROM 2-4 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 4-5 FT
BEYOND 20 NM.

TUESDAY...WINDS WILL BE SOMEWHAT ELEVATED ACROSS THE MARINE
COMMUNITY FOR MID-LATE AUGUST...WITH A SOMEWHAT ENHANCED GRADIENT
BETWEEN THE SUB-TROPICAL ATLANTIC RIDGE TO THE SE AND SOUTH AND AN
INLAND TROUGH TO THE NW. GIVEN SOME BOOST FROM THE SEA BREEZE
CIRCULATIONS SW AND SOUTH WINDS WILL PEAK AS HIGH AS 15-20 KT. SEAS
WILL HOLD AT OR BELOW 4 FT. MARINERS ARE ADVISED THAT SOME STRONGER
STORMS WILL MOVE OFF THE COAST IN THE LATE AFTERNOON AND EARLY AT
NIGHT. SOME OF THESE WILL PRODUCE FREQUENT LIGHTNING STRIKES...HEAVY
RAINS AND POSSIBLE WIND GUSTS IN EXCESS OF 30-40 KT.

WEDNESDAY THROUGH THURSDAY...THE PATTERN TRENDS TOWARD MORE TRANQUIL
CONDITIONS AS THE GRADIENT GRADUALLY RELAXES BETWEEN THE INLAND
TROUGH AND THE RIDGING ACROSS FLORIDA. WEST AND SW WINDS WILL HOLD
UNDER 10 OR 15 KT AND SEA AT OR BELOW 3 FT.

FRIDAY THROUGH SATURDAY...AN UPSTREAM COLD FRONT WILL APPROACH
FRIDAY AND LOOKS TO SHIFTS THROUGH ON SATURDAY...AS WINDS CLOCK
AROUND TO THE NE. EVEN SO WE DON/T ANTICIPATE THE NEED FOR ANY SMALL
CRAFT ADVISORY HEADLINES.

&&

.CLIMATE...
RECORD MAX TEMPS...
TUE 8/19...
KCHS 98 SET IN 1983
KCXM 98 SET IN 1895
KSAV 99 SET IN 1900 AND PREVIOUS

WED 8/20...
KCHS 97 SET IN 2005 AND PREVIOUS
KCXM 99 SET IN 1902
KSAV 102 SET IN 1900

THU 8/21...
KCHS 100 SET IN 1983
KCXM 99 SET IN 1900
KSAV 101 SET IN 1902

FRI 8/22...
KCHS 100 SET IN 1983
KCXM 98 SET IN 1983
KSAV 100 SET IN 1983

LAST TIME 100 DEGREES OR HIGHER...
KCHS JUNE 21 2011
KCXM JUNE 20 2011
KSAV JULY 26 2013

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...33
LONG TERM...JRL
AVIATION...33/SPR
MARINE...33/SPR
CLIMATE...
EQUIPMENT...






000
FXUS62 KFFC 181920
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
320 PM EDT MON AUG 18 2014

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20


&&

.PREV DISCUSSION... /ISSUED 127 PM EDT MON AUG 18 2014/

AVIATION...
18Z UPDATE...
SCATTERED CONVECTION HAS DEVELOPED IN AREAS THAT HAVE RECEIVED
THE BETTER HEATING THIS MORNING. NO REAL FOCUSING MECHANISM AT THE
SURFACE OR ALOFT. POTENT SHORTWAVE ACROSS NORTHERN MS WILL MOVE
EAST ACROSS AL THIS AFTERNOON. MORE ORGANIZED PRECIP IS POSSIBLE
WITH THIS FEATURE...BUT THE HI-RES MODELS DON`T HAVE A GREAT
HANDLE ON THE SITUATION. WILL LEAVE OUT ANY TEMPO/PROB GROUPS AT
THIS TIME. MODELS ALSO HAVE SOME LOW CLOUDS DEVELOPING...BUT IT
MAY BE LATER DUE TO ANY PRECIP.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ALL ELEMENTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          73  91  72  97 /  50  40  30  10
ATLANTA         74  88  73  94 /  40  40  30  10
BLAIRSVILLE     67  84  67  90 /  50  40  30  20
CARTERSVILLE    72  89  71  94 /  50  40  30  10
COLUMBUS        75  92  73  96 /  60  40  30  10
GAINESVILLE     72  89  71  94 /  50  40  30  10
MACON           75  92  72  97 /  50  40  30  10
ROME            72  89  71  95 /  60  40  30  20
PEACHTREE CITY  73  89  71  94 /  50  40  30  10
VIDALIA         77  95  74  97 /  50  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...
LONG TERM....ATWELL
AVIATION...NLISTEMAA





000
FXUS62 KFFC 181920
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
320 PM EDT MON AUG 18 2014

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
STALLED FRONTAL BOUNDARY STRETCHES FROM THE TN VALLEY TO THE
SOUTHERN MID ATLANTIC STATES. A HIGH PRESSURE RIDGE IS SITUATED
ACROSS NORTHERN FL. 500MB ANALYSIS AND WV LOOP SHOWS A POTENT
SHORTWAVE MOVING EAST ACROSS NORTHERN MS. THIS FEATURE WILL BE THE
FOCUS FOR LATE AFTERNOON AND EVENING CONVECTION ACROSS THE CWFA.

THE 16Z HRRR HAS THE BEST HANDLE ON THE ONGOING CONVECTION THIS
AFTERNOON. HAVE TRIED TO ORIENT THE POPS ACCORDING TO CURRENT RADAR
TRENDS AND CLOSE TO THE HRRR SOLUTION. GOOD INSTABILITY DOES EXIST
AT THE SURFACE...BUT LAPSE RATES REMAIN POOR UNTIL THE COLD POOL
ALOFT MOVES OVERHEAD. BY THE TIME THE SHORTWAVE NEARS THE
CWFA...INSTABILITY HAS DECREASED WITH THE LOSS OF HEATING.
HOWEVER...WITH UNIDIRECTIONAL FLOW...STORMS MAY MOVE REPEATEDLY OVER
THE SAME AREAS...WITH LOCALLY HEAVY RAINFALL POSSIBLE. AREAS TO THE
NORTH RECEIVED ONE TO TWO INCHES OF RAINFALL OVERNIGHT/EARLY THIS
MORNING...SO ANY TRAINING STORMS OR HEAVY RAINFALL MAY CAUSE SOME
LOCALIZED FLOODING.

BY EARLY TUESDAY...THE POTENT EVENING/OVERNIGHT SHORTWAVE WILL HAVE
MOVED OFF TO THE EAST. MODELS ARE PROGGING ANOTHER...WEAKER...
SHORTWAVE TO MOVE EAST IN THE FLOW TOMORROW. CONFIDENCE IS LOW ON
EXACTLY WHERE CONVECTION WILL DEVELOP TOMORROW.

NLISTEMAA

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
LONG TERM FORECAST IS ON TRACK AND HAVE NOT MADE SIGNIFICANT
ADJUSTMENTS. ONE ADDITIONAL POINT TO NOTE IS THAT HEAT INDEX VALUES
ARE CREEPING ABOVE 100 DEGREES SOUTH OF AN ATLANTA TO ATHENS
LINE...WITH PORTIONS OF CENTRAL GEORGIA APPROACHING 105 DEGREES
DURING THE SECOND HALF OF THE WEEK. IF THIS TREND CONTINUES...MAY
NEED A HEAT ADVISORY FOR THESE 105-108 DEGREE VALUES ACROSS THE
SOUTHEAST PART OF THE CWA.

11/ATWELL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20


&&

.PREV DISCUSSION... /ISSUED 127 PM EDT MON AUG 18 2014/

AVIATION...
18Z UPDATE...
SCATTERED CONVECTION HAS DEVELOPED IN AREAS THAT HAVE RECEIVED
THE BETTER HEATING THIS MORNING. NO REAL FOCUSING MECHANISM AT THE
SURFACE OR ALOFT. POTENT SHORTWAVE ACROSS NORTHERN MS WILL MOVE
EAST ACROSS AL THIS AFTERNOON. MORE ORGANIZED PRECIP IS POSSIBLE
WITH THIS FEATURE...BUT THE HI-RES MODELS DON`T HAVE A GREAT
HANDLE ON THE SITUATION. WILL LEAVE OUT ANY TEMPO/PROB GROUPS AT
THIS TIME. MODELS ALSO HAVE SOME LOW CLOUDS DEVELOPING...BUT IT
MAY BE LATER DUE TO ANY PRECIP.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ALL ELEMENTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          73  91  72  97 /  50  40  30  10
ATLANTA         74  88  73  94 /  40  40  30  10
BLAIRSVILLE     67  84  67  90 /  50  40  30  20
CARTERSVILLE    72  89  71  94 /  50  40  30  10
COLUMBUS        75  92  73  96 /  60  40  30  10
GAINESVILLE     72  89  71  94 /  50  40  30  10
MACON           75  92  72  97 /  50  40  30  10
ROME            72  89  71  95 /  60  40  30  20
PEACHTREE CITY  73  89  71  94 /  50  40  30  10
VIDALIA         77  95  74  97 /  50  40  30  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...
LONG TERM....ATWELL
AVIATION...NLISTEMAA






000
FXUS62 KCHS 181739
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
139 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MONDAY AFTERNOON...INLAND RADAR TRENDS AND 850-500 MB WINDS
20-25 KT SUGGEST AN INCREASING CHANCE FOR MULTICELL THUNDERSTORMS
WITH AN ISOLATED THREAT FOR DAMAGING WIND GUSTS TO PUSH INTO
COUNTIES NORTH OF I-16 THIS MID TO LATE AFTERNOON...PERHAPS
ADVANCING TOWARD THE COAST INCLUDING THE CHARLESTON TRI-COUNTY
REGION LATE AFTERNOON INTO EARLY EVENING. BUMPED POPS INTO THE
35-50 PERCENT RANGE FOR NOW...AND LOCALLY HIGHER POPS COULD
EVENTUALLY BE REQUIRED. MLCAPES 2500-3500 J/KG AND DCAPES AROUND
1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED...BRIEF PULSE SEVERE
EPISODES WITH DAMAGING WET MICROBURSTS. ADDED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS TO THE HAZARDOUS WEATHER OUTLOOK.

ELSEWHERE...SUBTLE/ MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE
DEEP LAYER WEST WIND REGIME AND INTERACTING WITH A SSW-NNE
SURFACE-850 MB THETA-E AXIS SHOULD SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS ALONG/SOUTH OF I-16. ALSO...THE OFFSHORE FLOW WILL
PIN THE SEA BREEZE NEAR THE COAST...AND THE RESULTING CONVERGENCE
COULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS OVER COASTAL
COUNTIES AND ADJACENT NEARSHORE WATER THIS AFTERNOON. IN THESE
AREAS...INSTABILITY COULD SUPPORT AN ISOLATED/BRIEF DAMAGING WET
MICROBURST THREAT.

OTHERWISE...EXPECT ANOTHER HOT AFTERNOON WITH HIGHS IN THE
MID 90S MOST AREAS AWAY FROM THE BEACHES. MAX HEAT INDEX VALUES
WILL TOP OUT 100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS
NEAR THE COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS
DEWPOINTS SURGE NEAR THE SEA BREEZE...BUT POTENTIAL COVERAGE/
DURATION WILL NOT JUSTIFY A HEAT ADVISORY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /17Z MONDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON.
CONFIDENCE IS INCREASING FOR DIRECT IMPACTS AT KCHS BETWEEN 21Z
AND 24Z...THUS ADDED AN APPROPRIATE TEMPO GROUP. AT KSAV...THE
POTENTIAL FOR DIRECT IMPACTS REMAINS UNCLEAR....THUS MAINTAINED
A PERIOD OF CB/VCTS INTO EARLY EVENING. WILL AMEND AS DICTATED BY
NEAR TERM CONVECTIVE TRENDS. THUNDERSTORMS WILL REDEVELOP
TUESDAY...BUT MOST LIKELY NOT BEFORE 18Z.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...






000
FXUS62 KCHS 181739
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
139 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MONDAY AFTERNOON...INLAND RADAR TRENDS AND 850-500 MB WINDS
20-25 KT SUGGEST AN INCREASING CHANCE FOR MULTICELL THUNDERSTORMS
WITH AN ISOLATED THREAT FOR DAMAGING WIND GUSTS TO PUSH INTO
COUNTIES NORTH OF I-16 THIS MID TO LATE AFTERNOON...PERHAPS
ADVANCING TOWARD THE COAST INCLUDING THE CHARLESTON TRI-COUNTY
REGION LATE AFTERNOON INTO EARLY EVENING. BUMPED POPS INTO THE
35-50 PERCENT RANGE FOR NOW...AND LOCALLY HIGHER POPS COULD
EVENTUALLY BE REQUIRED. MLCAPES 2500-3500 J/KG AND DCAPES AROUND
1000 J/KG SUGGEST A POTENTIAL FOR ISOLATED...BRIEF PULSE SEVERE
EPISODES WITH DAMAGING WET MICROBURSTS. ADDED A MENTION OF
ISOLATED SEVERE THUNDERSTORMS TO THE HAZARDOUS WEATHER OUTLOOK.

ELSEWHERE...SUBTLE/ MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE
DEEP LAYER WEST WIND REGIME AND INTERACTING WITH A SSW-NNE
SURFACE-850 MB THETA-E AXIS SHOULD SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS ALONG/SOUTH OF I-16. ALSO...THE OFFSHORE FLOW WILL
PIN THE SEA BREEZE NEAR THE COAST...AND THE RESULTING CONVERGENCE
COULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS OVER COASTAL
COUNTIES AND ADJACENT NEARSHORE WATER THIS AFTERNOON. IN THESE
AREAS...INSTABILITY COULD SUPPORT AN ISOLATED/BRIEF DAMAGING WET
MICROBURST THREAT.

OTHERWISE...EXPECT ANOTHER HOT AFTERNOON WITH HIGHS IN THE
MID 90S MOST AREAS AWAY FROM THE BEACHES. MAX HEAT INDEX VALUES
WILL TOP OUT 100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS
NEAR THE COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS
DEWPOINTS SURGE NEAR THE SEA BREEZE...BUT POTENTIAL COVERAGE/
DURATION WILL NOT JUSTIFY A HEAT ADVISORY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /17Z MONDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON.
CONFIDENCE IS INCREASING FOR DIRECT IMPACTS AT KCHS BETWEEN 21Z
AND 24Z...THUS ADDED AN APPROPRIATE TEMPO GROUP. AT KSAV...THE
POTENTIAL FOR DIRECT IMPACTS REMAINS UNCLEAR....THUS MAINTAINED
A PERIOD OF CB/VCTS INTO EARLY EVENING. WILL AMEND AS DICTATED BY
NEAR TERM CONVECTIVE TRENDS. THUNDERSTORMS WILL REDEVELOP
TUESDAY...BUT MOST LIKELY NOT BEFORE 18Z.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...







000
FXUS62 KCAE 181728
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
128 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-LEVEL
SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE INTO
THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE AND THIS MAY BE
CORRECT BECAUSE THE SURFACE FEATURE IS WEAK AND THE STRONGER
UPPER-LEVEL LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH IS PASSING
NORTH OF THE FORECAST AREA. EARLY AFTERNOON SURFACE-BASED LI/S WERE
-7 TO -8. THE STRONG INSTABILITY SUPPORTS A POSSIBILITY OF
DAMAGING WIND WITH A FEW OF THE THUNDERSTORMS. EXPECT AFTERNOON
TEMPERATURES WILL PEAK IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. EARLY AFTERNOON SURFACE-
BASED LI/S WERE -7 TO -8. THE STRONG INSTABILITY SUPPORTS STRONG
WINDS NEAR ANY THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 181728
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
128 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-LEVEL
SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE INTO
THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE AND THIS MAY BE
CORRECT BECAUSE THE SURFACE FEATURE IS WEAK AND THE STRONGER
UPPER-LEVEL LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH IS PASSING
NORTH OF THE FORECAST AREA. EARLY AFTERNOON SURFACE-BASED LI/S WERE
-7 TO -8. THE STRONG INSTABILITY SUPPORTS A POSSIBILITY OF
DAMAGING WIND WITH A FEW OF THE THUNDERSTORMS. EXPECT AFTERNOON
TEMPERATURES WILL PEAK IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. EARLY AFTERNOON SURFACE-
BASED LI/S WERE -7 TO -8. THE STRONG INSTABILITY SUPPORTS STRONG
WINDS NEAR ANY THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KFFC 181727
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
127 PM EDT MON AUG 18 2014



.PREV DISCUSSION... /ISSUED 1032 AM EDT MON AUG 18 2014/

UPDATE...
500MB AND WV ANALYSIS SHOWS A POTENT SHORTWAVE MOVING ACROSS
SOUTHERN TN/N GA THIS MORNING. AN AREA OF SHOWERS AND A FEW
THUNDERSTORMS WILL CONTINUE ACROSS THE NORTHERN ZONES FOR THE NEXT
FEW HOURS. MAIN UPDATES WERE TO THE POPS...AND HOURLY DEWPOINT GRIDS.

PREV DISCUSSION... /ISSUED 718 AM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 403 AM EDT MON AUG 18 2014/

SHORT TERM /TODAY THROUGH TUESDAY/...
TAIL END OF A SHORT WAVE TROUGH SEEMS TO BE AFFECTING FAR N GA WITH
SOME SHOWERS AND ISOLATED THUNDERSTORMS AND THE MODELS SEEM TO
INDICATE THIS WILL PLAY A ROLE AS ANOTHER VORTICITY MAX MOVES ACROSS
THE AREA LATER TODAY. THIS WILL FAVOR N GA WITH THE HIGHEST POPS AND
AND A LITTLE LESS SO FOR CENTRAL GA.

INSTABILITY WILL BE SUFFICIENT THAT A FEW STORMS COULD BECOME STRONG
AND ISOLATED SEVERE STORMS CAN NOT BE RULED OUT...ESPECIALLY FROM
CSG-MCN AND N.

MODELS RATHER CONSISTENT WITH BRINGING ANOTHER SHORT WAVE TO THE
AREA LATE TONIGHT AND ACROSS THE AREA THE FIRST PART OF TUESDAY.
VERY UNSURE IF THE PASSAGE WILL SHUT DOWN SHOWER AND STORM
DEVELOPMENT OR JUST LESSEN IT FOR TUESDAY. INSTABILITY DIMINISHES
OVERNIGHT SO THUNDERSTORM CHANCES WILL BE LOWER BUT INSTABILITY
SHOULD INCREASE AGAIN FOR TUESDAY. HIGHEST POPS ON TUESDAY LOOK TO
BE OVER EAST CENTRAL GA.

TEMPERATURES A DIFFICULT FORECAST AS WELL. FORECAST HIGH
TEMPERATURES RUNNING NEAR TO SLIGHTLY ABOVE NORMAL TODAY AND NEAR TO
SLIGHTLY BELOW NORMAL FOR TUESDAY. FORECAST LOW TEMPERATURES RUNNING
3-5 DEGREES ABOVE NORMAL TONIGHT.

OVERALL CONFIDENCE IS LOW TO MEDIUM.

BDL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20



&&

.AVIATION...
18Z UPDATE...
SCATTERED CONVECTION HAS DEVELOPED IN AREAS THAT HAVE RECEIVED THE
BETTER HEATING THIS MORNING. NO REAL FOCUSING MECHANISM AT THE
SURFACE OR ALOFT. POTENT SHORTWAVE ACROSS NORTHERN MS WILL MOVE
EAST ACROSS AL THIS AFTERNOON. MORE ORGANIZED PRECIP IS POSSIBLE
WITH THIS FEATURE...BUT THE HI-RES MODELS DON`T HAVE A GREAT
HANDLE ON THE SITUATION. WILL LEAVE OUT ANY TEMPO/PROB GROUPS AT
THIS TIME. MODELS ALSO HAVE SOME LOW CLOUDS DEVELOPING...BUT IT
MAY BE LATER DUE TO ANY PRECIP.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ALL ELEMENTS.



&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          92  74  90  72 /  40  50  30  20
ATLANTA         88  74  87  73 /  40  50  30  20
BLAIRSVILLE     82  68  83  67 / 100  50  30  30
CARTERSVILLE    88  73  87  69 /  50  50  30  20
COLUMBUS        92  77  90  74 /  40  50  30  20
GAINESVILLE     88  73  85  72 /  40  50  30  20
MACON           92  75  90  72 /  30  50  40  20
ROME            86  74  88  69 /  60  50  30  20
PEACHTREE CITY  89  74  87  71 /  40  50  30  20
VIDALIA         95  78  94  75 /  30  50  50  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$







000
FXUS62 KFFC 181727
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
127 PM EDT MON AUG 18 2014



.PREV DISCUSSION... /ISSUED 1032 AM EDT MON AUG 18 2014/

UPDATE...
500MB AND WV ANALYSIS SHOWS A POTENT SHORTWAVE MOVING ACROSS
SOUTHERN TN/N GA THIS MORNING. AN AREA OF SHOWERS AND A FEW
THUNDERSTORMS WILL CONTINUE ACROSS THE NORTHERN ZONES FOR THE NEXT
FEW HOURS. MAIN UPDATES WERE TO THE POPS...AND HOURLY DEWPOINT GRIDS.

PREV DISCUSSION... /ISSUED 718 AM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 403 AM EDT MON AUG 18 2014/

SHORT TERM /TODAY THROUGH TUESDAY/...
TAIL END OF A SHORT WAVE TROUGH SEEMS TO BE AFFECTING FAR N GA WITH
SOME SHOWERS AND ISOLATED THUNDERSTORMS AND THE MODELS SEEM TO
INDICATE THIS WILL PLAY A ROLE AS ANOTHER VORTICITY MAX MOVES ACROSS
THE AREA LATER TODAY. THIS WILL FAVOR N GA WITH THE HIGHEST POPS AND
AND A LITTLE LESS SO FOR CENTRAL GA.

INSTABILITY WILL BE SUFFICIENT THAT A FEW STORMS COULD BECOME STRONG
AND ISOLATED SEVERE STORMS CAN NOT BE RULED OUT...ESPECIALLY FROM
CSG-MCN AND N.

MODELS RATHER CONSISTENT WITH BRINGING ANOTHER SHORT WAVE TO THE
AREA LATE TONIGHT AND ACROSS THE AREA THE FIRST PART OF TUESDAY.
VERY UNSURE IF THE PASSAGE WILL SHUT DOWN SHOWER AND STORM
DEVELOPMENT OR JUST LESSEN IT FOR TUESDAY. INSTABILITY DIMINISHES
OVERNIGHT SO THUNDERSTORM CHANCES WILL BE LOWER BUT INSTABILITY
SHOULD INCREASE AGAIN FOR TUESDAY. HIGHEST POPS ON TUESDAY LOOK TO
BE OVER EAST CENTRAL GA.

TEMPERATURES A DIFFICULT FORECAST AS WELL. FORECAST HIGH
TEMPERATURES RUNNING NEAR TO SLIGHTLY ABOVE NORMAL TODAY AND NEAR TO
SLIGHTLY BELOW NORMAL FOR TUESDAY. FORECAST LOW TEMPERATURES RUNNING
3-5 DEGREES ABOVE NORMAL TONIGHT.

OVERALL CONFIDENCE IS LOW TO MEDIUM.

BDL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20



&&

.AVIATION...
18Z UPDATE...
SCATTERED CONVECTION HAS DEVELOPED IN AREAS THAT HAVE RECEIVED THE
BETTER HEATING THIS MORNING. NO REAL FOCUSING MECHANISM AT THE
SURFACE OR ALOFT. POTENT SHORTWAVE ACROSS NORTHERN MS WILL MOVE
EAST ACROSS AL THIS AFTERNOON. MORE ORGANIZED PRECIP IS POSSIBLE
WITH THIS FEATURE...BUT THE HI-RES MODELS DON`T HAVE A GREAT
HANDLE ON THE SITUATION. WILL LEAVE OUT ANY TEMPO/PROB GROUPS AT
THIS TIME. MODELS ALSO HAVE SOME LOW CLOUDS DEVELOPING...BUT IT
MAY BE LATER DUE TO ANY PRECIP.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ALL ELEMENTS.



&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          92  74  90  72 /  40  50  30  20
ATLANTA         88  74  87  73 /  40  50  30  20
BLAIRSVILLE     82  68  83  67 / 100  50  30  30
CARTERSVILLE    88  73  87  69 /  50  50  30  20
COLUMBUS        92  77  90  74 /  40  50  30  20
GAINESVILLE     88  73  85  72 /  40  50  30  20
MACON           92  75  90  72 /  30  50  40  20
ROME            86  74  88  69 /  60  50  30  20
PEACHTREE CITY  89  74  87  71 /  40  50  30  20
VIDALIA         95  78  94  75 /  30  50  50  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








000
FXUS62 KCAE 181658
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1258 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-LEVEL
SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE INTO
THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE AND THIS MAY BE
CORRECT BECAUSE THE SURFACE FEATURE IS WEAK AND THE STRONGER
UPPER-LEVEL LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH IS PASSING
NORTH OF THE FORECAST AREA. INSTABILITY HAS BECOME MODERATE. LATE
MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES WILL
LIKELY BE -7 TO -8. THE MODERATE TO STRONG INSTABILITY SUPPORTS
A POSSIBILITY OF DAMAGING WIND WITH A FEW OF THE THUNDERSTORMS.
EXPECT AFTERNOON TEMPERATURES WILL PEAK IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. WE DID NOT INCLUDE
THUNDERSTORMS IN THE TERMINAL FORECASTS BECAUSE OF THIS COVERAGE
AND TIMING UNCERTAINTY. INSTABILITY WILL BE MODERATE TO STRONG.
LATE MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES
WILL LIKELY BE -7 TO -8. EXPECT VERY STRONG WINDS NEAR ANY
THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KCAE 181658
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1258 PM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH TUESDAY. SOME DRIER AIR AND A
BUILDING UPPER RIDGE JUST TO OUR WEST WILL REDUCE AFTERNOON
THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY...AND LEAD TO
INCREASING HIGH TEMPERATURES. AN APPROACHING BACKDOOR FRONT AND
INCREASING MOISTURE WILL LEAD TO GREATER THUNDERSTORM CHANCES OVER
THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-LEVEL
SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE INTO
THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE AND THIS MAY BE
CORRECT BECAUSE THE SURFACE FEATURE IS WEAK AND THE STRONGER
UPPER-LEVEL LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH IS PASSING
NORTH OF THE FORECAST AREA. INSTABILITY HAS BECOME MODERATE. LATE
MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES WILL
LIKELY BE -7 TO -8. THE MODERATE TO STRONG INSTABILITY SUPPORTS
A POSSIBILITY OF DAMAGING WIND WITH A FEW OF THE THUNDERSTORMS.
EXPECT AFTERNOON TEMPERATURES WILL PEAK IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
ANOTHER UPPER SHORT WAVE WILL TRACK EAST ACROSS OUR FA
TUESDAY...WITH CONTINUED INDICATIONS OF A SUFFICIENTLY MOIST AND
UNSTABLE ATMOSPHERE TO SUPPORT CHANCE OF THUNDERSTORMS.

UPPER RIDGE WILL BUILD JUST TO OUR WEST STARTING WED. WARMING 850MB
TEMPERATURES AND A LOW LEVEL DOWNSLOPE FLOW WILL RESULT IN MAX
TEMPERATURES PUSHING 100 DEGREES WED/THU. LATEST GUIDANCE
INDICATES DEWPOINTS MIXING DOWN INTO THE MID TO UPPER 60S N FA TO
NEAR 70 TO THE LOWER 70S SE FA WED/THU AFTN...WHICH KEEPS MAX HEAT
INDEX VALUES JUST BELOW OUR HEAT ADVISORY CRITERIA OF 110. WITH A
DRY BULB TEMP OF 100...A DEWPOINT OF 72 IS NEEDED TO REACH A HEAT
INDEX OF 110. THIS WILL HAVE TO BE MONITORED. SOME DRIER AIR WILL
ENTER OUR FA WEDNESDAY. EXPECT LOWER PRECIPITATION CHANCES ON
WED/THU GIVEN THE DRIER AIR AND BUILDING RIDGE ALOFT.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
UPPER RIDGE TO OUR WEST WITH UPPER TROUGH AND CLOSED LOW TO OUR
NE...PROVIDING A NW FLOW ALOFT FOR OUR FA. SOME TIMING
UNCERTAINTIES...BUT MODELS SUGGEST A BACK DOOR FRONT WILL MOVE DOWN
THE EAST COAST...REACHING OUR FA SOME TIME THIS WEEKEND. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER DURING THAT TIME.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. WE DID NOT INCLUDE
THUNDERSTORMS IN THE TERMINAL FORECASTS BECAUSE OF THIS COVERAGE
AND TIMING UNCERTAINTY. INSTABILITY WILL BE MODERATE TO STRONG.
LATE MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES
WILL LIKELY BE -7 TO -8. EXPECT VERY STRONG WINDS NEAR ANY
THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCHS 181651
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1251 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MONDAY AFTERNOON...SHIFTED HIGHEST POPS...STILL LIMITED TO
25-35 PERCENT...INTO INLAND COUNTIES AND SOUTH OF I-16.

THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS. MEANWHILE...
THE OFFSHORE FLOW WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE
RESULTING CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS OVER COASTAL COUNTIES AND ADJACENT NEARSHORE WATER
THIS AFTERNOON. MLCAPES 2500-3500 J/KG AND DCAPES AROUND 1000 J/KG
SUGGEST A POTENTIAL FOR ISOLATED...BRIEF PULSE SEVERE EPISODES
WITH DAMAGING WET MICROBURSTS. HOWEVER...THE RESIDUAL CAP COULD
LIMIT THE STRENGTH/PERSISTENCE OF DEEP MOIST UPDRAFTS AND THE
ASSOCIATED THREAT FOR SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT WILL CONTINUE TO SUPPORT
MULTICELL THUNDERSTORMS WITHIN A BAND OF 0-6 KM SHEAR 25-30 KT/
0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA/MAINLY SC COUNTIES LATER THIS AFTERNOON/EARLY THIS
EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD DEVELOP
FOR A FEW HOURS. HOWEVER...LATEST GUIDANCE SUGGESTS THAT STRONGEST
MULTICELL THUNDERSTORMS COULD PASS NORTH OF THE FORECAST AREA.
FORECAST CONFIDENCE REMAINS LESS THAN IDEAL...WILL CONTINUE TO
ASSESS.

OTHERWISE...EXPECT ANOTHER HOT AFTERNOON WITH HIGHS IN THE
MID 90S MOST AREAS AWAY FROM THE BEACHES. MAX HEAT INDEX VALUES
WILL TOP OUT 100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS
NEAR THE COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS
DEWPOINTS SURGE NEAR THE SEA BREEZE...BUT POTENTIAL COVERAGE/
DURATION WILL NOT JUSTIFY A HEAT ADVISORY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON BUT THE
POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY WINDS AND FLIGHT
RESTRICTIONS REMAINS UNCLEAR. 18Z TAFS WILL MAINTAIN A PERIOD OF
CB/VCTS INTO EARLY EVENING...AND WILL AMEND AS NEEDED.
THUNDERSTORMS WILL REDEVELOP TUESDAY...BUT MORE LIKELY AFTER 18Z.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...







000
FXUS62 KCHS 181651
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1251 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MONDAY AFTERNOON...SHIFTED HIGHEST POPS...STILL LIMITED TO
25-35 PERCENT...INTO INLAND COUNTIES AND SOUTH OF I-16.

THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS. MEANWHILE...
THE OFFSHORE FLOW WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE
RESULTING CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS OVER COASTAL COUNTIES AND ADJACENT NEARSHORE WATER
THIS AFTERNOON. MLCAPES 2500-3500 J/KG AND DCAPES AROUND 1000 J/KG
SUGGEST A POTENTIAL FOR ISOLATED...BRIEF PULSE SEVERE EPISODES
WITH DAMAGING WET MICROBURSTS. HOWEVER...THE RESIDUAL CAP COULD
LIMIT THE STRENGTH/PERSISTENCE OF DEEP MOIST UPDRAFTS AND THE
ASSOCIATED THREAT FOR SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT WILL CONTINUE TO SUPPORT
MULTICELL THUNDERSTORMS WITHIN A BAND OF 0-6 KM SHEAR 25-30 KT/
0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA/MAINLY SC COUNTIES LATER THIS AFTERNOON/EARLY THIS
EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD DEVELOP
FOR A FEW HOURS. HOWEVER...LATEST GUIDANCE SUGGESTS THAT STRONGEST
MULTICELL THUNDERSTORMS COULD PASS NORTH OF THE FORECAST AREA.
FORECAST CONFIDENCE REMAINS LESS THAN IDEAL...WILL CONTINUE TO
ASSESS.

OTHERWISE...EXPECT ANOTHER HOT AFTERNOON WITH HIGHS IN THE
MID 90S MOST AREAS AWAY FROM THE BEACHES. MAX HEAT INDEX VALUES
WILL TOP OUT 100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS
NEAR THE COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS
DEWPOINTS SURGE NEAR THE SEA BREEZE...BUT POTENTIAL COVERAGE/
DURATION WILL NOT JUSTIFY A HEAT ADVISORY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON BUT THE
POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY WINDS AND FLIGHT
RESTRICTIONS REMAINS UNCLEAR. 18Z TAFS WILL MAINTAIN A PERIOD OF
CB/VCTS INTO EARLY EVENING...AND WILL AMEND AS NEEDED.
THUNDERSTORMS WILL REDEVELOP TUESDAY...BUT MORE LIKELY AFTER 18Z.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...







000
FXUS62 KCHS 181651
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1251 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MONDAY AFTERNOON...SHIFTED HIGHEST POPS...STILL LIMITED TO
25-35 PERCENT...INTO INLAND COUNTIES AND SOUTH OF I-16.

THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS. MEANWHILE...
THE OFFSHORE FLOW WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE
RESULTING CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS OVER COASTAL COUNTIES AND ADJACENT NEARSHORE WATER
THIS AFTERNOON. MLCAPES 2500-3500 J/KG AND DCAPES AROUND 1000 J/KG
SUGGEST A POTENTIAL FOR ISOLATED...BRIEF PULSE SEVERE EPISODES
WITH DAMAGING WET MICROBURSTS. HOWEVER...THE RESIDUAL CAP COULD
LIMIT THE STRENGTH/PERSISTENCE OF DEEP MOIST UPDRAFTS AND THE
ASSOCIATED THREAT FOR SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT WILL CONTINUE TO SUPPORT
MULTICELL THUNDERSTORMS WITHIN A BAND OF 0-6 KM SHEAR 25-30 KT/
0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA/MAINLY SC COUNTIES LATER THIS AFTERNOON/EARLY THIS
EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD DEVELOP
FOR A FEW HOURS. HOWEVER...LATEST GUIDANCE SUGGESTS THAT STRONGEST
MULTICELL THUNDERSTORMS COULD PASS NORTH OF THE FORECAST AREA.
FORECAST CONFIDENCE REMAINS LESS THAN IDEAL...WILL CONTINUE TO
ASSESS.

OTHERWISE...EXPECT ANOTHER HOT AFTERNOON WITH HIGHS IN THE
MID 90S MOST AREAS AWAY FROM THE BEACHES. MAX HEAT INDEX VALUES
WILL TOP OUT 100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS
NEAR THE COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS
DEWPOINTS SURGE NEAR THE SEA BREEZE...BUT POTENTIAL COVERAGE/
DURATION WILL NOT JUSTIFY A HEAT ADVISORY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON BUT THE
POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY WINDS AND FLIGHT
RESTRICTIONS REMAINS UNCLEAR. 18Z TAFS WILL MAINTAIN A PERIOD OF
CB/VCTS INTO EARLY EVENING...AND WILL AMEND AS NEEDED.
THUNDERSTORMS WILL REDEVELOP TUESDAY...BUT MORE LIKELY AFTER 18Z.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...







000
FXUS62 KCHS 181651
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1251 PM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MONDAY AFTERNOON...SHIFTED HIGHEST POPS...STILL LIMITED TO
25-35 PERCENT...INTO INLAND COUNTIES AND SOUTH OF I-16.

THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS. MEANWHILE...
THE OFFSHORE FLOW WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE
RESULTING CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED
THUNDERSTORMS OVER COASTAL COUNTIES AND ADJACENT NEARSHORE WATER
THIS AFTERNOON. MLCAPES 2500-3500 J/KG AND DCAPES AROUND 1000 J/KG
SUGGEST A POTENTIAL FOR ISOLATED...BRIEF PULSE SEVERE EPISODES
WITH DAMAGING WET MICROBURSTS. HOWEVER...THE RESIDUAL CAP COULD
LIMIT THE STRENGTH/PERSISTENCE OF DEEP MOIST UPDRAFTS AND THE
ASSOCIATED THREAT FOR SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT WILL CONTINUE TO SUPPORT
MULTICELL THUNDERSTORMS WITHIN A BAND OF 0-6 KM SHEAR 25-30 KT/
0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA/MAINLY SC COUNTIES LATER THIS AFTERNOON/EARLY THIS
EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD DEVELOP
FOR A FEW HOURS. HOWEVER...LATEST GUIDANCE SUGGESTS THAT STRONGEST
MULTICELL THUNDERSTORMS COULD PASS NORTH OF THE FORECAST AREA.
FORECAST CONFIDENCE REMAINS LESS THAN IDEAL...WILL CONTINUE TO
ASSESS.

OTHERWISE...EXPECT ANOTHER HOT AFTERNOON WITH HIGHS IN THE
MID 90S MOST AREAS AWAY FROM THE BEACHES. MAX HEAT INDEX VALUES
WILL TOP OUT 100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS
NEAR THE COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS
DEWPOINTS SURGE NEAR THE SEA BREEZE...BUT POTENTIAL COVERAGE/
DURATION WILL NOT JUSTIFY A HEAT ADVISORY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH 18Z TUESDAY. THUNDERSTORMS SHOULD
DEVELOP IN THE VICINITY OF THE TERMINALS THIS AFTERNOON BUT THE
POTENTIAL FOR DIRECT IMPACTS INCLUDING GUSTY WINDS AND FLIGHT
RESTRICTIONS REMAINS UNCLEAR. 18Z TAFS WILL MAINTAIN A PERIOD OF
CB/VCTS INTO EARLY EVENING...AND WILL AMEND AS NEEDED.
THUNDERSTORMS WILL REDEVELOP TUESDAY...BUT MORE LIKELY AFTER 18Z.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...







000
FXUS62 KCAE 181550
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1150 AM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS THROUGH TUESDAY.
SOME DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL
REDUCE AFTERNOON THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY. AN
APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-LEVEL
SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE INTO
THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE AND THIS MAY BE
CORRECT BECAUSE THE SURFACE FEATURE IS WEAK AND THE STRONGER
UPPER-LEVEL LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH IS PASSING
NORTH OF THE FORECAST AREA. INSTABILITY HAS BECOME MODERATE. LATE
MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES WILL
LIKELY BE -7 TO -8. THE MODERATE TO STRONG INSTABILITY SUPPORTS
A POSSIBILITY OF DAMAGING WIND WITH A FEW OF THE THUNDERSTORMS.
EXPECT AFTERNOON TEMPERATURES WILL PEAK IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
YET ANOTHER SHORTWAVE TROUGH WILL APPROACH THE FORECAST AREA
TUESDAY AFTERNOON TO COMBINE WITH ABUNDANT MOISTURE IN PLACE AND
RESULT IN SCATTERED DIURNALLY BASED CONVECTION. WILL MAINTAIN THE
MID CHANCE POPS INHERITED FROM PREVIOUS FORECAST AS THERE IS NOT
REASON TO DEVIATE AT THIS TIME. EXPECT ABUNDANT CLOUD COVER ON
TUESDAY WITH SOME CONVECTIVE DEBRIS CLOUDS OVER THE AREA TUESDAY
MORNING AND CONVECTION DEVELOPING IN THE AFTERNOON WHICH SHOULD
HELP KEEP TEMPERATURES DOWN A BIT IN THE LOWER TO MID 90S.

UPPER HEIGHTS RISE ON WEDNESDAY AND THURSDAY DUE TO A BUILDING
UPPER RIDGE JUST WEST OF THE FORECAST AREA AND 850MB TEMPERATURES
WARM TO AROUND +21C TO +22C. THIS WILL RESULT IN MAX TEMPERATURES
PUSHING THROUGH THE MID AND UPPER 90S WITH SOME 100 DEGREE
READINGS VERY POSSIBLE. DEVELOPING NORTHWESTERLY DOWNSLOPING LOW
LEVEL FLOW WILL ALSO CONTRIBUTE TO ABOVE NORMAL TEMPERATURES MID
WEEK WHILE HELPING TO DRY OUT THE MID LEVELS. EXPECT LOWER
PRECIPITATION CHANCES ON WED/THU GIVEN THE DRIER AIR AND BUILDING
RIDGE ALOFT. OVERNIGHT LOWS LIKELY TO BE ABOVE NORMAL IN THE LOWER
TO MID 70S.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
LITTLE CHANGE MADE DURING THIS PERIOD.

WHILE THERE REMAINS SOME TIMING DIFFERENCES...BOTH GFS/ECMWF
SUGGEST BACK DOOR FRONT TO MOVE DOWN THE EAST COAST...REACHING OUR
AREA SOME TIME FRIDAY NIGHT INTO EARLY SATURDAY. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. DIFFICULT TO PINPOINT DETAILS RELATED TO THIS
BACKDOOR FRONT...BUT WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER OVER THE WEEKEND.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. WE DID NOT INCLUDE
THUNDERSTORMS IN THE TERMINAL FORECASTS BECAUSE OF THIS COVERAGE
AND TIMING UNCERTAINTY. INSTABILITY WILL BE MODERATE TO STRONG.
LATE MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES
WILL LIKELY BE -7 TO -8. EXPECT VERY STRONG WINDS NEAR ANY
THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$






000
FXUS62 KCAE 181550
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1150 AM EDT MON AUG 18 2014

.SYNOPSIS...
AN UPPER TROUGH AND INCREASING MOISTURE WILL BRING THE CHANCE FOR
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS THROUGH TUESDAY.
SOME DRIER AIR AND A BUILDING UPPER RIDGE JUST TO OUR WEST WILL
REDUCE AFTERNOON THUNDERSTORM CHANCES WEDNESDAY AND THURSDAY. AN
APPROACHING BACKDOOR FRONT AND INCREASING MOISTURE WILL LEAD TO
GREATER THUNDERSTORM CHANCES OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...MOISTURE HAS INCREASED AHEAD OF THE MID-LEVEL
SHORTWAVE TROUGH. THIS MOISTURE PLUS HEATING AND CONVERGENCE INTO
THE LEE-SIDE TROUGH SHOULD HELP SUPPORT THUNDERSTORMS. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE AND THIS MAY BE
CORRECT BECAUSE THE SURFACE FEATURE IS WEAK AND THE STRONGER
UPPER-LEVEL LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH IS PASSING
NORTH OF THE FORECAST AREA. INSTABILITY HAS BECOME MODERATE. LATE
MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES WILL
LIKELY BE -7 TO -8. THE MODERATE TO STRONG INSTABILITY SUPPORTS
A POSSIBILITY OF DAMAGING WIND WITH A FEW OF THE THUNDERSTORMS.
EXPECT AFTERNOON TEMPERATURES WILL PEAK IN THE MIDDLE 90S.

TONIGHT...MOST OF THE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE
TROUGH SHOULD BE NORTHEAST OF THE FORECAST AREA THIS EVENING. THE
NAM INDICATES THE NEXT TROUGH NEARING THE AREA DURING THE EARLY
MORNING HOURS. THE MODELS MAINTAIN WEAK SURFACE TROUGHING. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS WITH THE GREATER CHANCE IN
THE EVENING CLOSER TO THE TIME OF MAXIMUM HEATING. SOME CLOUDINESS
AND MIXING SHOULD HELP HOLD UP TEMPERATURES. THE GUIDANCE WAS
CLOSE WITH LOWS MAINLY IN THE MIDDLE 70S.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
YET ANOTHER SHORTWAVE TROUGH WILL APPROACH THE FORECAST AREA
TUESDAY AFTERNOON TO COMBINE WITH ABUNDANT MOISTURE IN PLACE AND
RESULT IN SCATTERED DIURNALLY BASED CONVECTION. WILL MAINTAIN THE
MID CHANCE POPS INHERITED FROM PREVIOUS FORECAST AS THERE IS NOT
REASON TO DEVIATE AT THIS TIME. EXPECT ABUNDANT CLOUD COVER ON
TUESDAY WITH SOME CONVECTIVE DEBRIS CLOUDS OVER THE AREA TUESDAY
MORNING AND CONVECTION DEVELOPING IN THE AFTERNOON WHICH SHOULD
HELP KEEP TEMPERATURES DOWN A BIT IN THE LOWER TO MID 90S.

UPPER HEIGHTS RISE ON WEDNESDAY AND THURSDAY DUE TO A BUILDING
UPPER RIDGE JUST WEST OF THE FORECAST AREA AND 850MB TEMPERATURES
WARM TO AROUND +21C TO +22C. THIS WILL RESULT IN MAX TEMPERATURES
PUSHING THROUGH THE MID AND UPPER 90S WITH SOME 100 DEGREE
READINGS VERY POSSIBLE. DEVELOPING NORTHWESTERLY DOWNSLOPING LOW
LEVEL FLOW WILL ALSO CONTRIBUTE TO ABOVE NORMAL TEMPERATURES MID
WEEK WHILE HELPING TO DRY OUT THE MID LEVELS. EXPECT LOWER
PRECIPITATION CHANCES ON WED/THU GIVEN THE DRIER AIR AND BUILDING
RIDGE ALOFT. OVERNIGHT LOWS LIKELY TO BE ABOVE NORMAL IN THE LOWER
TO MID 70S.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
LITTLE CHANGE MADE DURING THIS PERIOD.

WHILE THERE REMAINS SOME TIMING DIFFERENCES...BOTH GFS/ECMWF
SUGGEST BACK DOOR FRONT TO MOVE DOWN THE EAST COAST...REACHING OUR
AREA SOME TIME FRIDAY NIGHT INTO EARLY SATURDAY. THIS WOULD
INCREASE POPS ALONG AND SOUTH OF THE BOUNDARY...AND LEAD TO COOLER
TEMPS NORTH OF IT. DIFFICULT TO PINPOINT DETAILS RELATED TO THIS
BACKDOOR FRONT...BUT WILL MAINTAIN TREND IN THE ONGOING FORECAST OF
POPS TRENDING HIGHER AND TEMPS TRENDING LOWER OVER THE WEEKEND.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. MOISTURE AND
INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH...
HEATING...AND CONVERGENCE INTO A LEE-SIDE SURFACE TROUGH SHOULD
HELP SUPPORT THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. MUCH
OF THE LIFT ASSOCIATED WITH THE UPPER-LEVEL FEATURE IS PASSING
NORTH OF THE FORECAST AREA. THE SURFACE TROUGH IS WEAK.
THEREFORE...EXPECT LIMITED THUNDERSTORM COVERAGE. THE HIGH-
RESOLUTION MODELS DISPLAY SCATTERED COVERAGE. WE DID NOT INCLUDE
THUNDERSTORMS IN THE TERMINAL FORECASTS BECAUSE OF THIS COVERAGE
AND TIMING UNCERTAINTY. INSTABILITY WILL BE MODERATE TO STRONG.
LATE MORNING SURFACE-BASED LI/S WERE NEAR -6. AFTERNOON VALUES
WILL LIKELY BE -7 TO -8. EXPECT VERY STRONG WINDS NEAR ANY
THUNDERSTORMS.

THERE MAY BE STRATUS AND FOG DURING THE EARLY MORNING HOURS.
HOWEVER...HIGHER CLOUDINESS SHOULD LIMIT NET RADIATIONAL COOLING
AND EXPECT SOME MIXING WILL CONTINUE. MOST OF THE NAM AND GFS MOS
MAINTAINED VFR CONDITIONS AND THE SREF PROBABILITIES OF
RESTRICTIVE CEILINGS OR FOG WERE LESS THAN 20 PERCENT.

EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS POSSIBLE IN LATE
NIGHT AND EARLY MORNING FOG THROUGH THE PERIOD. SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS MAY ALSO BRING RESTRICTIONS.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







000
FXUS62 KFFC 181432
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1032 AM EDT MON AUG 18 2014



.UPDATE...
500MB AND WV ANALYSIS SHOWS A POTENT SHORTWAVE MOVING ACROSS
SOUTHERN TN/N GA THIS MORNING. AN AREA OF SHOWERS AND A FEW
THUNDERSTORMS WILL CONTINUE ACROSS THE NORTHERN ZONES FOR THE NEXT
FEW HOURS. MAIN UPDATES WERE TO THE POPS...AND HOURLY DEWPOINT GRIDS.

&&



.PREV DISCUSSION... /ISSUED 718 AM EDT MON AUG 18 2014/

PREV DISCUSSION... /ISSUED 403 AM EDT MON AUG 18 2014/

SHORT TERM /TODAY THROUGH TUESDAY/...
TAIL END OF A SHORT WAVE TROUGH SEEMS TO BE AFFECTING FAR N GA WITH
SOME SHOWERS AND ISOLATED THUNDERSTORMS AND THE MODELS SEEM TO
INDICATE THIS WILL PLAY A ROLE AS ANOTHER VORTICITY MAX MOVES ACROSS
THE AREA LATER TODAY. THIS WILL FAVOR N GA WITH THE HIGHEST POPS AND
AND A LITTLE LESS SO FOR CENTRAL GA.

INSTABILITY WILL BE SUFFICIENT THAT A FEW STORMS COULD BECOME STRONG
AND ISOLATED SEVERE STORMS CAN NOT BE RULED OUT...ESPECIALLY FROM
CSG-MCN AND N.

MODELS RATHER CONSISTENT WITH BRINGING ANOTHER SHORT WAVE TO THE
AREA LATE TONIGHT AND ACROSS THE AREA THE FIRST PART OF TUESDAY.
VERY UNSURE IF THE PASSAGE WILL SHUT DOWN SHOWER AND STORM
DEVELOPMENT OR JUST LESSEN IT FOR TUESDAY. INSTABILITY DIMINISHES
OVERNIGHT SO THUNDERSTORM CHANCES WILL BE LOWER BUT INSTABILITY
SHOULD INCREASE AGAIN FOR TUESDAY. HIGHEST POPS ON TUESDAY LOOK TO
BE OVER EAST CENTRAL GA.

TEMPERATURES A DIFFICULT FORECAST AS WELL. FORECAST HIGH
TEMPERATURES RUNNING NEAR TO SLIGHTLY ABOVE NORMAL TODAY AND NEAR TO
SLIGHTLY BELOW NORMAL FOR TUESDAY. FORECAST LOW TEMPERATURES RUNNING
3-5 DEGREES ABOVE NORMAL TONIGHT.

OVERALL CONFIDENCE IS LOW TO MEDIUM.

BDL

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GFS AND ECMWF ARE IN UNCOMMONLY GOOD AGREEMENT THROUGH THE
EXTENDED FORECAST PERIOD AND CONTINUE THE RECENT TREND OF BUILDING
UPPER-LEVEL HIGH PRESSURE INTO THE CENTRAL GULF COAST REGION AND
LOWER MISSISSIPPI VALLEY FROM MID-WEEK THROUGH NEXT WEEKEND. BY THE
WEEKEND THE UPPER RIDGE IS QUITE STRONG...BUT GEORGIA REMAINS ON THE
EASTERN PERIPHERY. THIS SHOULD ALLOW VERY WARM TEMPERATURES AND
INHIBIT DIURNAL CONVECTION SOMEWHAT...BUT I DO NOT BELIEVE THE
FORECAST AREA IS CLOSE ENOUGH TO THE CENTER OF THE RIDGE TO
ELIMINATE POPS ALTOGETHER.

20

AVIATION...
12Z UPDATE...
IFR CEILINGS EXPECTED TO IMPROVE TO VFR LATER THIS MORNING.
ONGOING STORMS TO THE NORTH EXPECTED TO STAY MAINLY NORTH BUT
COULD ENHANCE A FLAIR UP OF STORMS LATER TODAY. GENERALLY LOW
CONFIDENCE TO IMPACTS TO THE TAF SITES. SURFACE WINDS INCREASING
10-15 KTS WITH SOME GUSTS 20+ KTS.

//ATL CONFIDENCE...12Z UPDATE...
LOW CONFIDENCE FOR CEILINGS/VSBYS/IMPACTS FROM THUNDERSTORMS.
MEDIUM CONFIDENCE FOR WIND SPEED
HIGH CONFIDENCE FOR WIND DIRECTION.

BDL

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          92  74  90  72 /  30  50  30  20
ATLANTA         88  74  87  73 /  40  50  30  20
BLAIRSVILLE     82  68  83  67 / 100  50  30  30
CARTERSVILLE    88  73  87  69 /  50  50  30  20
COLUMBUS        92  77  90  74 /  40  50  30  20
GAINESVILLE     88  73  85  72 /  40  50  30  20
MACON           92  75  90  72 /  30  50  40  20
ROME            86  74  88  69 /  60  50  30  20
PEACHTREE CITY  89  74  87  71 /  40  50  30  20
VIDALIA         95  78  94  75 /  30  50  50  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$







000
FXUS62 KCHS 181414
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1014 AM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS ACROSS
INLAND COUNTIES...ESPECIALLY ACROSS SE GA...WHERE MAX AFTERNOON
POPS REMAIN IN THE 25-30 PERCENT RANGE. MEANWHILE...THE OFFSHORE
WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE RESULTING
CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS OVER
COASTAL COUNTIES AND ADJACENT NEARSHORE WATER THIS AFTERNOON.
IN THESE AREAS...DESPITE MLCAPES 2000-3000 J/KG THE RESIDUAL CAP
COULD INHIBIT DEEP MOIST UPDRAFTS AND THE ASSOCIATED THREAT FOR
SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT SUPPORTED CLUSTERS OF
THUNDERSTORMS LATE MONDAY MORNING. ADDITIONAL MULTICELL
THUNDERSTORMS SHOULD DEVELOP WITHIN A BAND OF 0-6 KM SHEAR 25-30
KT/0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA...MAINLY SC COUNTIES...LATER THIS AFTERNOON/EARLY
THIS EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD
DEVELOP FOR A FEW HOURS. HOWEVER...GUIDANCE DIFFERS REGARDING THE
SOUTHWARD EXTENT OF MULTICELL THUNDERSTORMS...SO FORECAST
CONFIDENCE REMAINS LESS THAN IDEAL.

OTHERWISE...EXPECT ANOTHER HOT DAY WITH HIGHS IN THE MID/UPPER 90S
SWAY FROM THE BEACHES...EVEN AROUND 90F UNTIL THE SEA BREEZE
DEVELOP ON THE BEACHES. MAX HEAT INDEX VALUES WILL TOP OUT
100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS NEAR THE
COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS DEWPOINTS SURGE
NEAR THE SEA BREEZE...BUT COVERAGE/DURATION WILL NOT JUSTIFY A
HEAT ADVISORY.



&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL THROUGH 12Z TUESDAY. ISOLATED TO SCATTERED
CONVECTION IS POSSIBLE AFTER MID AFTERNOON AT BOTH TERMINALS AND
CHANCES ARE DECENT THAT THUNDER WILL BE AROUND THE VICINITY THIS
AFTERNOON. A STRONG RESULTANT SEA BREEZE WILL BE GENERALLY PINNED
TO THE COAST WITH INCREASING MOISTURE AND INSTABILITY EXPECTED
WITH TIME. GOOD LOW LEVEL WIND FIELDS TONIGHT SHOULD PRECLUDE ANY
CONCERNS FOR LATE NIGHT VSBY RESTRICTIONS FROM FOG/MIST.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...






000
FXUS62 KCHS 181414
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1014 AM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS ACROSS
INLAND COUNTIES...ESPECIALLY ACROSS SE GA...WHERE MAX AFTERNOON
POPS REMAIN IN THE 25-30 PERCENT RANGE. MEANWHILE...THE OFFSHORE
WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE RESULTING
CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS OVER
COASTAL COUNTIES AND ADJACENT NEARSHORE WATER THIS AFTERNOON.
IN THESE AREAS...DESPITE MLCAPES 2000-3000 J/KG THE RESIDUAL CAP
COULD INHIBIT DEEP MOIST UPDRAFTS AND THE ASSOCIATED THREAT FOR
SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT SUPPORTED CLUSTERS OF
THUNDERSTORMS LATE MONDAY MORNING. ADDITIONAL MULTICELL
THUNDERSTORMS SHOULD DEVELOP WITHIN A BAND OF 0-6 KM SHEAR 25-30
KT/0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA...MAINLY SC COUNTIES...LATER THIS AFTERNOON/EARLY
THIS EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD
DEVELOP FOR A FEW HOURS. HOWEVER...GUIDANCE DIFFERS REGARDING THE
SOUTHWARD EXTENT OF MULTICELL THUNDERSTORMS...SO FORECAST
CONFIDENCE REMAINS LESS THAN IDEAL.

OTHERWISE...EXPECT ANOTHER HOT DAY WITH HIGHS IN THE MID/UPPER 90S
SWAY FROM THE BEACHES...EVEN AROUND 90F UNTIL THE SEA BREEZE
DEVELOP ON THE BEACHES. MAX HEAT INDEX VALUES WILL TOP OUT
100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS NEAR THE
COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS DEWPOINTS SURGE
NEAR THE SEA BREEZE...BUT COVERAGE/DURATION WILL NOT JUSTIFY A
HEAT ADVISORY.



&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL THROUGH 12Z TUESDAY. ISOLATED TO SCATTERED
CONVECTION IS POSSIBLE AFTER MID AFTERNOON AT BOTH TERMINALS AND
CHANCES ARE DECENT THAT THUNDER WILL BE AROUND THE VICINITY THIS
AFTERNOON. A STRONG RESULTANT SEA BREEZE WILL BE GENERALLY PINNED
TO THE COAST WITH INCREASING MOISTURE AND INSTABILITY EXPECTED
WITH TIME. GOOD LOW LEVEL WIND FIELDS TONIGHT SHOULD PRECLUDE ANY
CONCERNS FOR LATE NIGHT VSBY RESTRICTIONS FROM FOG/MIST.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...






000
FXUS62 KCHS 181414
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1014 AM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS ACROSS
INLAND COUNTIES...ESPECIALLY ACROSS SE GA...WHERE MAX AFTERNOON
POPS REMAIN IN THE 25-30 PERCENT RANGE. MEANWHILE...THE OFFSHORE
WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE RESULTING
CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS OVER
COASTAL COUNTIES AND ADJACENT NEARSHORE WATER THIS AFTERNOON.
IN THESE AREAS...DESPITE MLCAPES 2000-3000 J/KG THE RESIDUAL CAP
COULD INHIBIT DEEP MOIST UPDRAFTS AND THE ASSOCIATED THREAT FOR
SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT SUPPORTED CLUSTERS OF
THUNDERSTORMS LATE MONDAY MORNING. ADDITIONAL MULTICELL
THUNDERSTORMS SHOULD DEVELOP WITHIN A BAND OF 0-6 KM SHEAR 25-30
KT/0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA...MAINLY SC COUNTIES...LATER THIS AFTERNOON/EARLY
THIS EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD
DEVELOP FOR A FEW HOURS. HOWEVER...GUIDANCE DIFFERS REGARDING THE
SOUTHWARD EXTENT OF MULTICELL THUNDERSTORMS...SO FORECAST
CONFIDENCE REMAINS LESS THAN IDEAL.

OTHERWISE...EXPECT ANOTHER HOT DAY WITH HIGHS IN THE MID/UPPER 90S
SWAY FROM THE BEACHES...EVEN AROUND 90F UNTIL THE SEA BREEZE
DEVELOP ON THE BEACHES. MAX HEAT INDEX VALUES WILL TOP OUT
100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS NEAR THE
COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS DEWPOINTS SURGE
NEAR THE SEA BREEZE...BUT COVERAGE/DURATION WILL NOT JUSTIFY A
HEAT ADVISORY.



&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL THROUGH 12Z TUESDAY. ISOLATED TO SCATTERED
CONVECTION IS POSSIBLE AFTER MID AFTERNOON AT BOTH TERMINALS AND
CHANCES ARE DECENT THAT THUNDER WILL BE AROUND THE VICINITY THIS
AFTERNOON. A STRONG RESULTANT SEA BREEZE WILL BE GENERALLY PINNED
TO THE COAST WITH INCREASING MOISTURE AND INSTABILITY EXPECTED
WITH TIME. GOOD LOW LEVEL WIND FIELDS TONIGHT SHOULD PRECLUDE ANY
CONCERNS FOR LATE NIGHT VSBY RESTRICTIONS FROM FOG/MIST.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...






000
FXUS62 KCHS 181414
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1014 AM EDT MON AUG 18 2014

.SYNOPSIS...
THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL REMAIN SOUTHEAST
OF THE REGION AND A TROUGH OF LOW PRESSURE WILL PREVAIL INLAND.
A COLD FRONT WILL ADVANCE THROUGH THE AREA THIS WEEKEND...THEN
HIGH PRESSURE WILL BUILD FROM THE NORTH INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE 12Z KCHS SOUNDING REVEALED DEEPER MOISTURE/SOMEWHAT WEAKER
CAPPING AS COMPARED WITH THE SUNDAY MORNING SOUNDING...AN
ENVIRONMENT MORE CONDUCIVE FOR SHOWERS/THUNDERSTORMS. SUBTLE/
MESOSCALE PERTURBATIONS EMBEDDED WITHIN THE DEEP LAYER WEST WIND
REGIME SHOULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS ACROSS
INLAND COUNTIES...ESPECIALLY ACROSS SE GA...WHERE MAX AFTERNOON
POPS REMAIN IN THE 25-30 PERCENT RANGE. MEANWHILE...THE OFFSHORE
WILL PIN THE SEA BREEZE NEAR THE COAST...AND THE RESULTING
CONVERGENCE COULD SUPPORT ISOLATED/SCATTERED THUNDERSTORMS OVER
COASTAL COUNTIES AND ADJACENT NEARSHORE WATER THIS AFTERNOON.
IN THESE AREAS...DESPITE MLCAPES 2000-3000 J/KG THE RESIDUAL CAP
COULD INHIBIT DEEP MOIST UPDRAFTS AND THE ASSOCIATED THREAT FOR
SEVERE WEATHER.

UPSTREAM...A SHORTWAVE TROUGH ALOFT SUPPORTED CLUSTERS OF
THUNDERSTORMS LATE MONDAY MORNING. ADDITIONAL MULTICELL
THUNDERSTORMS SHOULD DEVELOP WITHIN A BAND OF 0-6 KM SHEAR 25-30
KT/0-1 KM SHEAR 15-20 KT N/NW OF THE FORECAST AREA. IF ORGANIZED
THUNDERSTORMS DEVELOP SUFFICIENTLY FAR S/SW AND PUSH INTO THE
FORECAST AREA...MAINLY SC COUNTIES...LATER THIS AFTERNOON/EARLY
THIS EVENING AN ENHANCED THREAT FOR DAMAGING WIND GUSTS COULD
DEVELOP FOR A FEW HOURS. HOWEVER...GUIDANCE DIFFERS REGARDING THE
SOUTHWARD EXTENT OF MULTICELL THUNDERSTORMS...SO FORECAST
CONFIDENCE REMAINS LESS THAN IDEAL.

OTHERWISE...EXPECT ANOTHER HOT DAY WITH HIGHS IN THE MID/UPPER 90S
SWAY FROM THE BEACHES...EVEN AROUND 90F UNTIL THE SEA BREEZE
DEVELOP ON THE BEACHES. MAX HEAT INDEX VALUES WILL TOP OUT
100-106F AT MOST LOCATIONS. AT ISOLATED LOCATIONS NEAR THE
COAST...THE HEAT INDEX COULD BRIEFLY TOUCH 110F AS DEWPOINTS SURGE
NEAR THE SEA BREEZE...BUT COVERAGE/DURATION WILL NOT JUSTIFY A
HEAT ADVISORY.



&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
CONVECTION SHOULD DIMINISH OR MOVE OFFSHORE OF SOUTH CAROLINA COAST
AFTER MID EVENING WITH PARTLY CLOUDY SKIES ALL AREAS OVERNIGHT
ALONG WITH A LIGHT SW BREEZE. POPS SILENT AFTER MIDNIGHT WITH LOWS
73-77 DEGREES.

TUESDAY...A POTENT SHORTWAVE WILL PASS THROUGH SC DURING THE
EARLY TO MID AFTERNOON. A JUICY AIRMASS WILL BE IN PLACE WITH
PWATS ABOVE 2 INCHES. ALTHOUGH THE TIMING ON THE INCREASING SKY
COVER AND PRECIP COULD AFFECT HIGH TEMPS...STRONG WESTERLY FLOW IN
ADVANCE OF THE VORT MAX SUPPORT HIGH TEMPS REACHING THE MIDDLE 90S
MOST AREAS. CLUSTERS OF SHOWERS AND TSTMS EXPECTED TO DEVELOP
UPSTREAM AND EXPAND INTO THE AREA DURING THE AFTERNOON. ALTHOUGH
THE THERMODYNAMIC PROFILES ARE NOT GOING TO BE TOO TERRIBLY
IMPRESSIVE...GIVEN THE FORCING AND TIME OF YEAR WE CANNOT RULE OUT
A FEW SEVERE STORMS.

THE 500 MB RIDGE WILL GRADUALLY BUILD ACROSS THE AREA WEDNESDAY AND
THURSDAY WITH INCREASING UPPER HEIGHTS AND DEEP WNW FLOW. ASIDE FROM
SOME CIRRUS...SKIES SHOULD BE SUNNY BOTH DAYS WITH LATE AFTERNOON
SEA BREEZE CIRCULATIONS ALONG THE COAST. THICKNESSES SUPPORT HIGH
TEMPS IN THE UPPER 90S BOTH DAYS WITH TEMPS REACHING THE LOWER TO
MIDDLE 90S NEAR THE IMMEDIATE COAST. ON THURSDAY WE COULD EASILY SEE
SOME READINGS AT THE CENTURY MARK ACROSS INLAND GA. FAIRLY WARM MID
LEVELS AND LACK OF APPRECIABLE FORCING WILL ONLY SUPPORT ISOLATED
SHOWERS AND TSTMS BOTH DAYS. THE HEAT INDICES ARE THE MAIN CONCERN.
THE EXACT DEWPOINTS AT THE TIME OF MAX TEMP ARE CRITICAL TO
DETERMINING THE HEAT ADVISORY POTENTIAL. HOWEVER IT IS VERY
DIFFICULT TO PIN DOWN THE DEWPOINTS THIS FAR IN ADVANCE. OUR CURRENT
FORECAST SHOWS HEAT INDICES TOPPING OUT AT 106-109 ON WEDNESDAY AND
105-110 ON THURSDAY. WE CANNOT RULE OUT A HEAT ADVISORY FOR PORTIONS
OF THE AREA EITHER DAY...THOUGH THURSDAY IS LOOKING LIKE THE WORST
OF THE TWO DAYS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE UPPER RIDGE AXIS TO OUR WEST WILL BECOME MORE AMPLIFIED WHILE A
TROUGH CARVES OUT ACROSS THE MID-ATLANTIC REGION. MEDIUM RANGE
GUIDANCE IS IN GOOD AGREEMENT THAT A BACKDOOR COLD FRONT WILL DROP
TOWARD THE AREA ON FRIDAY...PUSHING THROUGH ON SATURDAY.
COMPRESSIONAL HEATING ON FRIDAY AHEAD OF THE FRONT WILL YIELD HIGHS
IN THE MID TO UPPER 90S. SOMEWHAT COOLER CANADIAN HIGH PRESSURE
BUILDS IN FROM THE NORTH SUNDAY INTO MONDAY WITH INCREASING RAIN
CHANCES AS BETTER CONVERGENCE DEVELOPS.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL THROUGH 12Z TUESDAY. ISOLATED TO SCATTERED
CONVECTION IS POSSIBLE AFTER MID AFTERNOON AT BOTH TERMINALS AND
CHANCES ARE DECENT THAT THUNDER WILL BE AROUND THE VICINITY THIS
AFTERNOON. A STRONG RESULTANT SEA BREEZE WILL BE GENERALLY PINNED
TO THE COAST WITH INCREASING MOISTURE AND INSTABILITY EXPECTED
WITH TIME. GOOD LOW LEVEL WIND FIELDS TONIGHT SHOULD PRECLUDE ANY
CONCERNS FOR LATE NIGHT VSBY RESTRICTIONS FROM FOG/MIST.

EXTENDED AVIATION OUTLOOK...ISOLATED TO SCATTERED AFTERNOON
SHRA/TSRA EXPECTED THROUGH FRIDAY WITH VERY BRIEF FLIGHT
RESTRICTIONS POSSIBLE.

&&

.MARINE...
THE COASTAL WATERS ARE BETWEEN A LOW PRES AREA OVER THE SOUTHERN
MID ATLC REGION AND HIGH PRES LODGED IN TO THE SOUTH. AN ENHANCED
PRES GRADIENT WILL SUPPORT SW FLOW 10 TO 15 KT WITH LATE DAY
ENHANCEMENTS. NOCTURNAL SURGING TONIGHT WILL RESULT IN A MORE
SOLID 15 KT ACROSS NEAR SHORE WATERS WITHIN 10 MILES AND UP
TO 20 KT ONCE AGAIN BEYOND THE PILOT BUOYS...ESPECIALLY FROM
GRAYS REEF SEAWARD. SEAS 2 TO 3 FT ON AVERAGE NEAR SHORE TODAY
AND 3 TO 4 FT TONIGHT. A PERIOD OF 5 FT WAVES ARE POSSIBLE IN
OUTER GEORGIA WATERS.

ATLANTIC HIGH PRESSURE TO THE SOUTHEAST AND AN INLAND TROUGH WILL
MAINTAIN AN ENHANCED SW WIND FLOW TUESDAY AND TUESDAY NIGHT WITH
WIND SPEEDS UPWARDS OF 15-20 KT. A RELAXING GRADIENT WEDNESDAY
THROUGH SATURDAY WILL DROP WINDS TO 15 KT OR LESS. OVER THE WEEKEND
A FRONT WILL DROP THROUGH THE WATERS WITH WINDS SWINGING AROUND TO
NE.

&&

.EQUIPMENT...
THE CHARLESTON SC WSR-88D /KCLX/ REMAINS OUT OF SERVICE DUE TO A
SIGNIFICANT MECHANICAL FAILURE. REPAIR WORK CONTINUES AND THE
RADAR COULD BECOME OPERATIONAL AS EARLY AS AUGUST 20TH OR 21ST.
UNTIL THE CHARLESTON SC RADAR RETURNS TO SERVICE...FOR DOPPLER
RADAR COVERAGE OF SOUTHEAST GEORGIA AND SOUTH COASTAL SOUTH
CAROLINA UTILIZE SURROUNDING RADARS INCLUDING KJAX...KJGX...
KVAX...KCAE AND KLTX.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...SPR
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...SPR
MARINE...JRL/SPR
EQUIPMENT...






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