[top]
000
FXUS61 KRLX 220537
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
109 AM EDT TUE MAY 22 2012
.SYNOPSIS...
WEAK COLD FRONT SLOWLY PUSHES EASTWARD OVERNIGHT. UPPER AIR SYSTEM
SLOWLY DRIFTS BY...JUST TO OUR SOUTH PROVIDING SLOW MOVING CONVECTION
THROUGH WEDNESDAY. WARMER AND DRIER AIR FOR THE END OF WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1030 PM UPDATE...TRIMMED POPS BACK OVERNIGHT AND INTO THE EARLY
MORNING HOURS AS IT APPEARS THAT MUCH OF THE SHOWER/THUNDERSTORM
ACTIVITY WILL WANE WITH THE LOSS OF DAYTIME INSTABILITY...NEARLY
MOIST ADIABATIC TEMP PROFILES...AND NO REAL DEEP LAYER MOISTURE
PRESENT. COVERAGE OF PRECIP IN FACT ALREADY BEGINNING TO DISSIPATE
OVERALL FROM EARLIER THIS EVENING...THOUGH SOME SHOWER AND
THUNDERSTORM ACTIVITY CONTINUES TO FORM OUT TO THE WEST OF THE
FORECAST AREA AND ALONG AN OUTFLOW BOUNDARY LOCATED JUST TO THE
EAST OF CRW DOWN TOWARDS BKW. ALSO REDUCED THREAT OF THUNDER AFTER
06Z OVERNIGHT FOR SAME REASONS MENTIONED.
PREVIOUS DISCUSSION...LATEST SURFACE MAP SHOWS A WEAK COLD FRONT WAS
LOCATED JUST TO OUR WEST. A WEAK AREA OF LOW PRESSURE WAS ALSO TO
OUR EAST. THIS FEATURE WAS RESPONSIBLE FOR CLOUDS AND SPRINKLES
ACROSS PORTIONS OF THE EASTERN WV PANHANDLE AS WELL AS PORTIONS OF
NORTH- CENTRAL WV.
OTHER STORMS HAD DEVELOPED ACROSS PORTIONS OF EASTERN KENTUCKY AND
THE WV MOUNTAIN COUNTIES.
THE COLD FRONT SHOULD EAST INTO THE REGION TONIGHT. MODELS
INDICATE AN UPPER LEVEL TROF WILL DEEPEN JUST TO OUR WEST TONIGHT
WITH MOST OF THE MODELS INDICATING AN UPPER LOW WILL DEVELOP. THE
NAM IS THE QUICKEST DEVELOPING A CLOSED LOW TO OUR SOUTHWEST AS
EARLY AS 12 UTC TUESDAY.
EXPECT SHOWER AND STORM CHANCES WILL INCREASE ACROSS THE
MOUNTAINS AND ACROSS PORTIONS OF SOUTHEAST OHIO...NORTHEAST
KENTUCKY AND THE SOUTHERN COALFIELDS THRU THE LATE EVENING HOURS.
IN RESPONSE TO THE COLD FRONT AND THE UPPER TROF...PRECIPITATION
CHANCES SHOULD THEN DEVELOP ACROSS MUCH OF THE REGION TONIGHT.
AS UPPER LEVEL TROF/LOW DRIFTS EAST ON TUESDAY...ALL OF THE MODELS
AS WELL AS HPC 6-HR QPF PRODUCT INDICATE MEASURABLE RAIN WILL BE A
GOOD BET ACROSS THE MOUNTAIN COUNTIES AND THE ADJACENT COUNTIES BY
TUESDAY AFTERNOON.
USED A BLEND OF MET/MAV GUIDANCE FOR LOWS TONIGHT. TEMP GUIDANCE
IS QUITE DIFFERENT FOR HIGHS ON TUESDAY...WITH THE DISCREPANCY A
DIFFERENCE OF 9 DEGREES AT KCRW. BECAUSE OF CLOUDS AND PRECIP...
WENT CLOSER TO THE COOLER MET NUMBERS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
EVEN THOUGH WE ARE NOT 70 DEW POINT AIR /SURFACE DEW POINTS INTO THE
LOWER 60S/ THE PRECIPITABLE WATER DOES GET OVER 1.25 INCHES. AM
CONCERNED ABOUT THE SLOW MOVEMENT ON ANY SHOWERS DURING THIS ENTIRE
TIME FRAME. THE MID LEVEL STEERING CURRENTS ARE MOSTLY UNDER 10
KNOTS. CERTAINLY NO DEFINITE BOUNDARIES TO FINE TUNE THE POPS...BUT
STILL THINKING MORE TOWARD THE MOUNTAINOUS COUNTIES FROM SOUTHWEST
VIRGINIA. WILL INCLUDE A HAZARD FOR WATER...JUST IN CASE THERE ARE
REPETITIVE SHOWERS OVER THE SAME BASIN.
HAVE THE HIGHER POPS TUESDAY NIGHT IN THE 60 TO 70 PERCENT RANGE
TUESDAY NIGHT...BUT STILL TRYING TO HOLD ONTO SOME LIKELY 60 POPS
OVER THE WV MOUNTAINOUS COUNTIES ON WEDNESDAY.
ALSO TRIED TO KEEP MOUNTAIN MAXIMUM TEMPERATURES ON THE LOW SIDE OF
GUIDANCE WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
LAST OF THE WEAKENING AND SLOW MOVING MID LEVEL TROF INCHING TO OUR
NE ON THURSDAY. A BIT CONCERNED THERE WAS STILL SOME SE COMPONENT
TO THE LOW LEVEL WINDS EARLY ON THURSDAY. SO LEAVING SOME 20 TO 30
POPS IN WV AND SW VA.
AIR CONTINUES TO WARM UP AND DRY OUT...BUT HAVE NO PROBLEMS LEAVING
SOME SLIGHT CHANCE POPS INTO SATURDAY OVER THE MOUNTAINOUS
COUNTIES.
OUR ATTENTION WILL GRADUALLY SWITCH FROM THE EAST TO THE NORTH.
WITH 500 MB RIDGE BUILDING TO OUR WEST...SOME GREAT LAKE CONVECTION
MAY KEEP DOWN SE AROUND THAT RIDGE OVER SATURDAY THROUGH SUNDAY
PERIOD. TRIED TO KEEP THAT CONVECTION TO OUR NORTH ON
SATURDAY...BUT WITH SOME 20/30 POPS BACK IN WV BY SUNDAY.
500 MB RIDGE MAY BE WEAKENING BY MONDAY MEMORIAL DAY. BUT NO
ORGANIZED FRONT EXPECTED TO BE NEAR. SO ONLY SLIGHT CHANCE POPS IN
THE HEAT OF THE DAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
THE ATMOSPHERE IS SATURATED WITH MOISTURE AT MOST LEVELS. THIS WILL
ALLOW FOR SOME CONTINUED CONVECTION THROUGH THE PERIOD...WITH BEST
COVERAGE DURING THE AFTERNOON AND EVENING HOURS. AREAS RECEIVING
RAINFALL COULD FORM SOME NOCTURNAL FOG BOTH EARLY THIS MORNING AND
TUESDAY NIGHT. OUTSIDE OF THE FOG AND CONVECTION...VFR CONDITIONS
WILL GENERALLY PREVAIL.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF SHOWERS/STORMS COULD VARY. WITH THE
ATMOSPHERE SATURATED AT MOST LEVELS...CLOUD DECKS COULD FORM AT
UNEXPECTED LEVELS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE TUE 05/22/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H L L H H H M H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H M H
AFTER 06Z WEDNESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/KTB
NEAR TERM...JSH/50
SHORT TERM...KTB
LONG TERM...KTB
AVIATION...RPY
000
FXUS61 KRLX 220237
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1037 PM EDT MON MAY 21 2012
.SYNOPSIS...
COLD FRONT ARRIVES TONIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS BY...JUST TO OUR SOUTH. SLOW MOVING CONVECTION THROUGH
WEDNESDAY. WARMER AIR TRIES TO DRY OUT ENVIRONMENT END OF WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
1030 PM UPDATE...TRIMMED POPS BACK OVERNIGHT AND INTO THE EARLY
MORNING HOURS AS IT APPEARS THAT MUCH OF THE SHOWER/THUNDERSTORM
ACTIVITY WILL WANE WITH THE LOSS OF DAYTIME INSTABILITY...NEARLY
MOIST ADIABATIC TEMP PROFILES...AND NO REAL DEEP LAYER MOISTURE
PRESENT. COVERAGE OF PRECIP IN FACT ALREADY BEGINNING TO DISSIPATE
OVERALL FROM EARLIER THIS EVENING...THOUGH SOME SHOWER AND
THUNDERSTORM ACTIVITY CONTINUES TO FORM OUT TO THE WEST OF THE
FORECAST AREA AND ALONG AN OUTFLOW BOUNDARY LOCATED JUST TO THE
EAST OF CRW DOWN TOWARDS BKW. ALSO REDUCED THREAT OF THUNDER AFTER
06Z OVERNIGHT FOR SAME REASONS MENTIONED.
PREVIOUS DISCUSSION...LATEST SURFACE MAP SHOWS A WEAK COLD FRONT WAS
LOCATED JUST TO OUR WEST. A WEAK AREA OF LOW PRESSURE WAS ALSO TO
OUR EAST. THIS FEATURE WAS RESPONSIBLE FOR CLOUDS AND SPRINKLES
ACROSS PORTIONS OF THE EASTERN WV PANHANDLE AS WELL AS PORTIONS OF
NORTH- CENTRAL WV.
OTHER STORMS HAD DEVELOPED ACROSS PORTIONS OF EASTERN KENTUCKY AND
THE WV MOUNTAIN COUNTIES.
THE COLD FRONT SHOULD EAST INTO THE REGION TONIGHT. MODELS
INDICATE AN UPPER LEVEL TROF WILL DEEPEN JUST TO OUR WEST TONIGHT
WITH MOST OF THE MODELS INDICATING AN UPPER LOW WILL DEVELOP. THE
NAM IS THE QUICKEST DEVELOPING A CLOSED LOW TO OUR SOUTHWEST AS
EARLY AS 12 UTC TUESDAY.
EXPECT SHOWER AND STORM CHANCES WILL INCREASE ACROSS THE
MOUNTAINS AND ACROSS PORTIONS OF SOUTHEAST OHIO...NORTHEAST
KENTUCKY AND THE SOUTHERN COALFIELDS THRU THE LATE EVENING HOURS.
IN RESPONSE TO THE COLD FRONT AND THE UPPER TROF...PRECIPITATION
CHANCES SHOULD THEN DEVELOP ACROSS MUCH OF THE REGION TONIGHT.
AS UPPER LEVEL TROF/LOW DRIFTS EAST ON TUESDAY...ALL OF THE MODELS
AS WELL AS HPC 6-HR QPF PRODUCT INDICATE MEASURABLE RAIN WILL BE A
GOOD BET ACROSS THE MOUNTAIN COUNTIES AND THE ADJACENT COUNTIES BY
TUESDAY AFTERNOON.
USED A BLEND OF MET/MAV GUIDANCE FOR LOWS TONIGHT. TEMP GUIDANCE
IS QUITE DIFFERENT FOR HIGHS ON TUESDAY...WITH THE DISCREPANCY A
DIFFERENCE OF 9 DEGREES AT KCRW. BECAUSE OF CLOUDS AND PRECIP...
WENT CLOSER TO THE COOLER MET NUMBERS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
EVEN THOUGH WE ARE NOT 70 DEW POINT AIR /SURFACE DEW POINTS INTO THE
LOWER 60S/ THE PRECIPITABLE WATER DOES GET OVER 1.25 INCHES. AM
CONCERNED ABOUT THE SLOW MOVEMENT ON ANY SHOWERS DURING THIS ENTIRE
TIME FRAME. THE MID LEVEL STEERING CURRENTS ARE MOSTLY UNDER 10
KNOTS. CERTAINLY NO DEFINITE BOUNDARIES TO FINETUNE THE POPS...BUT
STILL THINKING MORE TOWARD THE MOUNTAINOUS COUNTIES FROM SOUTHWEST
VIRGINIA. WILL INCLUDE A HAZARD FOR WATER...JUST IN CASE THERE ARE
REPETITIVE SHOWERS OVER THE SAME BASIN.
HAVE THE HIGHER POPS TUESDAY NIGHT IN THE 60 TO 70 PERCENT RANGE
TUESDAY NIGHT...BUT STILL TRYING TO HOLD ONTO SOME LIKELY 60 POPS
OVER THE WV MOUNTAINOUS COUNTIES ON WEDNESDAY.
ALSO TRIED TO KEEP MOUNTAIN MAXIMUM TEMPERATURES ON THE LOW SIDE OF
GUIDANCE WEDNESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
LAST OF THE WEAKENING AND SLOW MOVING MID LEVEL TROF INCHING TO OUR
NE ON THURSDAY. A BIT CONCERNED THERE WAS STILL SOME SE COMPONENT
TO THE LOW LEVEL WINDS EARLY ON THURSDAY. SO LEAVING SOME 20 TO 30
POPS IN WV AND SW VA.
AIR CONTINUES TO WARM UP AND DRY OUT...BUT HAVE NO PROBLEMS LEAVING
SOME SLIGHT CHANCE POPS INTO SATURDAY OVER THE MOUNTAINOUS
COUNTIES.
OUR ATTENTION WILL GRADUALLY SWITCH FROM THE EAST TO THE NORTH.
WITH 500 MB RIDGE BUILDING TO OUR WEST...SOME GREAT LAKE CONVECTION
MAY KEEP DOWN SE AROUND THAT RIDGE OVER SATURDAY THROUGH SUNDAY
PERIOD. TRIED TO KEEP THAT CONVECTION TO OUR NORTH ON
SATURDAY...BUT WITH SOME 20/30 POPS BACK IN WV BY SUNDAY.
500 MB RIDGE MAY BE WEAKENING BY MONDAY MEMORIAL DAY. BUT NO
ORGANIZED FRONT EXPECTED TO BE NEAR. SO ONLY SLIGHT CHANCE POPS IN
THE HEAT OF THE DAY.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THIS EVENING AND INTO THE
OVERNIGHT HOURS. SHORT TERM POINT SOUNDINGS INDICATE A LOW IFR
DECK DEVELOPING DURING THE EARLY MORNING HOURS ACROSS MAINLY SOUTHERN
PARTS OF THE AREA. THINKING THIS MAY BE OVERDONE A BIT WITH ANTICIPATED
OVERNIGHT RAINS NOT AS LIKELY AS PREVIOUSLY BELEIVED. NONETHELESS...FOR
NOW WILL GO AHEAD AND INCLUDE IFR CIGS BY MORNING. ONCE FORMED THEY
WILL BE HARD TO SCATTER BUT SHOULD AT LEAST RISE TO LOW MVFR WITH
DAYTIME WARMING. SHOWER AND THUNDERSTORM ACTIVITY WILL INCREASE ONCE
AGAIN DURING THE MORNING HOURS AND BECOME LIKELY ACROSS EASTERN PARTS
OF THE AREA DURING THE AFTERNOON HOURS. AS ALWAYS...INTERMITTENT
IFR CONDITIONS WILL BE POSSIBLE WITH ANY STRONGER STORMS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z WEDNESDAY...
FORECAST CONFIDENCE: HIGH THROUGH 03Z TUESDAY...THEN MEDIUM 03Z
THRU 18Z.
ALTERNATE SCENARIOS: TIMING OF SHOWERS/STORMS AND SUBSEQUENT
FLIGHT CONDITIONS THROUGH TUESDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE TUE 05/22/12
UTC 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
EDT 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09
CRW CONSISTENCY H H H H H H L L L L L L
HTS CONSISTENCY H H H H M M M M H H H H
BKW CONSISTENCY H H H H H H H H H H L M
EKN CONSISTENCY H H H H H H H L L L L L
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z WEDNESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS INTO WEDNESDAY...ESPECIALLY IN
THE MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/KTB
NEAR TERM...JSH/50
SHORT TERM...KTB
LONG TERM...KTB
AVIATION...50
000
FXUS61 KRLX 220000
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
800 PM EDT MON MAY 21 2012
.SYNOPSIS...
COLD FRONT ARRIVES TONIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS BY...JUST TO OUR SOUTH. SLOW MOVING CONVECTION THROUGH
WEDNESDAY. WARMER AIR TRIES TO DRY OUT ENVIRONMENT END OF WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
730 PM UPDATE...TRIMMED BACK POPS ACROSS CENTRAL AND WESTERN PARTS
OF THE FORECAST AREA THIS EVENING AS CONVECTIVE LINE OF SHOWERS
AND THUNDERSTORMS NOT MAKING MUCH HEADWAY EAST. WILL ALSO BE
TAKING A CLOSER LOOK AT OVERNIGHT/EARLY MORNING POPS FOR NEXT
UPDATE...POSSIBLY LOWERING A BIT.
PREVIOUS DISCUSSION...LATEST SURFACE MAP SHOWS A WEAK COLD FRONT WAS
LOCATED JUST TO OUR WEST. A WEAK AREA OF LOW PRESSURE WAS ALSO TO
OUR EAST. THIS FEATURE WAS RESPONSIBLE FOR CLOUDS AND SPRINKLES
ACROSS PORTIONS OF THE EASTERN WV PANHANDLE AS WELL AS PORTIONS OF
NORTH- CENTRAL WV.
OTHER STORMS HAD DEVELOPED ACROSS PORTIONS OF EASTERN KENTUCKY AND
THE WV MOUNTAIN COUNTIES.
THE COLD FRONT SHOULD EAST INTO THE REGION TONIGHT. MODELS
INDICATE AN UPPER LEVEL TROF WILL DEEPEN JUST TO OUR WEST TONIGHT
WITH MOST OF THE MODELS INDICATING AN UPPER LOW WILL DEVELOP. THE
NAM IS THE QUICKEST DEVELOPING A CLOSED LOW TO OUR SOUTHWEST AS
EARLY AS 12 UTC TUESDAY.
EXPECT SHOWER AND STORM CHANCES WILL INCREASE ACROSS THE
MOUNTAINS AND ACROSS PORTIONS OF SOUTHEAST OHIO...NORTHEAST
KENTUCKY AND THE SOUTHERN COALFIELDS THRU THE LATE EVENING HOURS.
IN RESPONSE TO THE COLD FRONT AND THE UPPER TROF...PRECIPITATION
CHANCES SHOULD THEN DEVELOP ACROSS MUCH OF THE REGION TONIGHT.
AS UPPER LEVEL TROF/LOW DRIFTS EAST ON TUESDAY...ALL OF THE MODELS
AS WELL AS HPC 6-HR QPF PRODUCT INDICATE MEASURABLE RAIN WILL BE A
GOOD BET ACROSS THE MOUNTAIN COUNTIES AND THE ADJACENT COUNTIES BY
TUESDAY AFTERNOON.
USED A BLEND OF MET/MAV GUIDANCE FOR LOWS TONIGHT. TEMP GUIDANCE
IS QUITE DIFFERENT FOR HIGHS ON TUESDAY...WITH THE DISCREPANCY A
DIFFERENCE OF 9 DEGREES AT KCRW. BECAUSE OF CLOUDS AND PRECIP...
WENT CLOSER TO THE COOLER MET NUMBERS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
EVEN THOUGH WE ARE NOT 70 DEW POINT AIR /SURFACE DEW POINTS INTO THE
LOWER 60S/ THE PRECIPITABLE WATER DOES GET OVER 1.25 INCHES. AM
CONCERNED ABOUT THE SLOW MOVEMENT ON ANY SHOWERS DURING THIS ENTIRE
TIME FRAME. THE MID LEVEL STEERING CURRENTS ARE MOSTLY UNDER 10
KNOTS. CERTAINLY NO DEFINITE BOUNDARIES TO FINETUNE THE POPS...BUT
STILL THINKING MORE TOWARD THE MOUNTAINOUS COUNTIES FROM SOUTHWEST
VIRGINIA. WILL INCLUDE A HAZARD FOR WATER...JUST IN CASE THERE ARE
REPETITIVE SHOWERS OVER THE SAME BASIN.
HAVE THE HIGHER POPS TUESDAY NIGHT IN THE 60 TO 70 PERCENT RANGE
TUESDAY NIGHT...BUT STILL TRYING TO HOLD ONTO SOME LIKELY 60 POPS
OVER THE WV MOUNTAINOUS COUNTIES ON WEDNESDAY.
ALSO TRIED TO KEEP MOUNTAIN MAXIMUM TEMPERATURES ON THE LOW SIDE OF
GUIDANCE WEDNESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
LAST OF THE WEAKENING AND SLOW MOVING MID LEVEL TROF INCHING TO OUR
NE ON THURSDAY. A BIT CONCERNED THERE WAS STILL SOME SE COMPONENT
TO THE LOW LEVEL WINDS EARLY ON THURSDAY. SO LEAVING SOME 20 TO 30
POPS IN WV AND SW VA.
AIR CONTINUES TO WARM UP AND DRY OUT...BUT HAVE NO PROBLEMS LEAVING
SOME SLIGHT CHANCE POPS INTO SATURDAY OVER THE MOUNTAINOUS
COUNTIES.
OUR ATTENTION WILL GRADUALLY SWITCH FROM THE EAST TO THE NORTH.
WITH 500 MB RIDGE BUILDING TO OUR WEST...SOME GREAT LAKE CONVECTION
MAY KEEP DOWN SE AROUND THAT RIDGE OVER SATURDAY THROUGH SUNDAY
PERIOD. TRIED TO KEEP THAT CONVECTION TO OUR NORTH ON
SATURDAY...BUT WITH SOME 20/30 POPS BACK IN WV BY SUNDAY.
500 MB RIDGE MAY BE WEAKENING BY MONDAY MEMORIAL DAY. BUT NO
ORGANIZED FRONT EXPECTED TO BE NEAR. SO ONLY SLIGHT CHANCE POPS IN
THE HEAT OF THE DAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THIS EVENING AND INTO THE
OVERNIGHT HOURS. SHORT TERM POINT SOUNDINGS INDICATE A LOW IFR
DECK DEVELOPING DURING THE EARLY MORNING HOURS ACROSS MAINLY SOUTHERN
PARTS OF THE AREA. THINKING THIS MAY BE OVERDONE A BIT WITH ANTICIPATED
OVERNIGHT RAINS NOT AS LIKELY AS PREVIOUSLY BELEIVED. NONETHELESS...FOR
NOW WILL GO AHEAD AND INCLUDE IFR CIGS BY MORNING. ONCE FORMED THEY
WILL BE HARD TO SCATTER BUT SHOULD AT LEAST RISE TO LOW MVFR WITH
DAYTIME WARMING. SHOWER AND THUNDERSTORM ACTIVITY WILL INCREASE ONCE
AGAIN DURING THE MORNING HOURS AND BECOME LIKELY ACROSS EASTERN PARTS
OF THE AREA DURING THE AFTERNOON HOURS. AS ALWAYS...INTERMITTENT
IFR CONDITIONS WILL BE POSSIBLE WITH ANY STRONGER STORMS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z WEDNESDAY...
FORECAST CONFIDENCE: HIGH THROUGH 03Z TUESDAY...THEN MEDIUM 03Z
THRU 18Z.
ALTERNATE SCENARIOS: TIMING OF SHOWERS/STORMS AND SUBSEQUENT
FLIGHT CONDITIONS THROUGH TUESDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE TUE 05/22/12
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H L L L
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z WEDNESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS INTO WEDNESDAY...ESPECIALLY IN
THE MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/KTB
NEAR TERM...JSH
SHORT TERM...KTB
LONG TERM...KTB
AVIATION...50
000
FXUS61 KRLX 211858
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
250 PM EDT MON MAY 21 2012
.SYNOPSIS...
COLD FRONT ARRIVES TONIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS BY...JUST TO OUR SOUTH. SLOW MOVING CONVECTION THROUGH
WEDNESDAY. WARMER AIR TRIES TO DRY OUT ENVIRONMENT END OF WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
LATEST SURFACE MAP SHOWS A WEAK COLD FRONT WAS LOCATED JUST TO OUR
WEST. A WEAK AREA OF LOW PRESSURE WAS ALSO TO OUR EAST. THIS
FEATURE WAS RESPONSIBLE FOR CLOUDS AND SPRINKLES ACROSS PORTIONS
OF THE EASTERN WV PANHANDLE AS WELL AS PORTIONS OF NORTH-CENTRAL WV.
OTHER STORMS HAD DEVELOPED ACROSS PORTIONS OF EASTERN KENTUCKY AND
THE WV MOUNTAIN COUNTIES.
THE COLD FRONT SHOULD EAST INTO THE REGION TONIGHT. MODELS
INDICATE AN UPPER LEVEL TROF WILL DEEPEN JUST TO OUR WEST TONIGHT
WITH MOST OF THE MODELS INDICATING AN UPPER LOW WILL DEVELOP. THE
NAM IS THE QUICKEST DEVELOPING A CLOSED LOW TO OUR SOUTHWEST AS
EARLY AS 12 UTC TUESDAY.
EXPECT SHOWER AND STORM CHANCES WILL INCREASE ACROSS THE
MOUNTAINS AND ACROSS PORTIONS OF SOUTHEAST OHIO...NORTHEAST
KENTUCKY AND THE SOUTHERN COALFIELDS THRU THE LATE EVENING HOURS.
IN RESPONSE TO THE COLD FRONT AND THE UPPER TROF...PRECIPITATION
CHANCES SHOULD THEN DEVELOP ACROSS MUCH OF THE REGION TONIGHT.
AS UPPER LEVEL TROF/LOW DRIFTS EAST ON TUESDAY...ALL OF THE MODELS
AS WELL AS HPC 6-HR QPF PRODUCT INDICATE MEASURABLE RAIN WILL BE A
GOOD BET ACROSS THE MOUNTAIN COUNTIES AND THE ADJACENT COUNTIES BY
TUESDAY AFTERNOON.
USED A BLEND OF MET/MAV GUIDANCE FOR LOWS TONIGHT. TEMP GUIDANCE
IS QUITE DIFFERENT FOR HIGHS ON TUESDAY...WITH THE DISCREPANCY A
DIFFERENCE OF 9 DEGREES AT KCRW. BECAUSE OF CLOUDS AND PRECIP...
WENT CLOSER TO THE COOLER MET NUMBERS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
EVEN THOUGH WE ARE NOT 70 DEW POINT AIR /SURFACE DEW POINTS INTO THE
LOWER 60S/ THE PRECIPITABLE WATER DOES GET OVER 1.25 INCHES. AM
CONCERNED ABOUT THE SLOW MOVEMENT ON ANY SHOWERS DURING THIS ENTIRE
TIME FRAME. THE MID LEVEL STEERING CURRENTS ARE MOSTLY UNDER 10
KNOTS. CERTAINLY NO DEFINITE BOUNDARIES TO FINETUNE THE POPS...BUT
STILL THINKING MORE TOWARD THE MOUNTAINOUS COUNTIES FROM SOUTHWEST
VIRGINIA. WILL INCLUDE A HAZARD FOR WATER...JUST IN CASE THERE ARE
REPETITIVE SHOWERS OVER THE SAME BASIN.
HAVE THE HIGHER POPS TUESDAY NIGHT IN THE 60 TO 70 PERCENT RANGE
TUESDAY NIGHT...BUT STILL TRYING TO HOLD ONTO SOME LIKELY 60 POPS
OVER THE WV MOUNTAINOUS COUNTIES ON WEDNESDAY.
ALSO TRIED TO KEEP MOUNTAIN MAXIMUM TEMPERATURES ON THE LOW SIDE OF
GUIDANCE WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
LAST OF THE WEAKENING AND SLOW MOVING MID LEVEL TROF INCHING TO OUR
NE ON THURSDAY. A BIT CONCERNED THERE WAS STILL SOME SE COMPONENT
TO THE LOW LEVEL WINDS EARLY ON THURSDAY. SO LEAVING SOME 20 TO 30
POPS IN WV AND SW VA.
AIR CONTINUES TO WARM UP AND DRY OUT...BUT HAVE NO PROBLEMS LEAVING
SOME SLIGHT CHANCE POPS INTO SATURDAY OVER THE MOUNTAINOUS
COUNTIES.
OUR ATTENTION WILL GRADUALLY SWITCH FROM THE EAST TO THE NORTH.
WITH 500 MB RIDGE BUILDING TO OUR WEST...SOME GREAT LAKE CONVECTION
MAY KEEP DOWN SE AROUND THAT RIDGE OVER SATURDAY THROUGH SUNDAY
PERIOD. TRIED TO KEEP THAT CONVECTION TO OUR NORTH ON
SATURDAY...BUT WITH SOME 20/30 POPS BACK IN WV BY SUNDAY.
500 MB RIDGE MAY BE WEAKENING BY MONDAY MEMORIAL DAY. BUT NO
ORGANIZED FRONT EXPECTED TO BE NEAR. SO ONLY SLIGHT CHANCE POPS IN
THE HEAT OF THE DAY.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
VFR CONDITIONS CAN BE EXPECTED AT MOST LOCATIONS THRU 03Z. THE
EXCEPTIONS WILL BE IN SHOWERS AND THUNDERSTORMS...WHERE IFR
CONDITIONS ARE POSSIBLE IN HEAVIER RAIN.
A COLD FRONT AND A DEVELOPING UPPER LEVEL FEATURE WILL AID IN THE
DEVELOPMENT OF CONVECTION LATE IN THE DAY...AND ENABLE THE
CONVECTION TO CONTINUE THROUGH 12Z. AREAS THAT RECEIVE RAINFALL
THIS AFTERNOON AND EVENING MAY HAVE FOG TONIGHT.
PRECIPITATION CHANCES WILL INCREASE BETWEEN 12Z AND 18Z ON TUESDAY
AS THE UPPER LEVEL FEATURE BEGINS TO DRIFT EAST. THE BEST CHANCES
FOR SHOWERS AND THUNDERSTORMS WILL BE ACROSS THE MOUNTAINS AND
ADJACENT COUNTIES...WHERE MVFR CONDITIONS ARE EXPECTED. ISOLATED
IFR CONDITIONS ARE POSSIBLE IN THE HEAVIER STORMS. ACROSS THE
REMAINDER OF THE REGION...VFR CONDITIONS ARE ANTICIPATED.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH 03Z TUESDAY...THEN MEDIUM 03Z
THRU 18Z.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND STORMS THROUGH TUESDAY
MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS INTO WEDNESDAY...ESPECIALLY IN
THE MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/KTB
NEAR TERM...JSH
SHORT TERM...KTB
LONG TERM...KTB
AVIATION...JSH
000
FXUS61 KRLX 211729
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
127 PM EDT MON MAY 21 2012
.SYNOPSIS...
COLD FRONT ARRIVES TONIGHT AND THEN WASHES OUT...AS AN UPPER
LEVEL SYSTEM DRIFTS BY...JUST TO OUR SOUTH. HIGH PRESSURE WILL
THEN RESULT IN VERY WARM WEATHER FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
LATEST SURFACE MAP SHOWS A WEAK COLD FRONT WAS LOCATED JUST TO OUR
WEST. A WEAK AREA OF LOW PRESSURE WAS ALSO TO OUR EAST. THIS
FEATURE WAS RESPONSIBLE FOR CLOUDS AND SPRINKLES ACROSS PORTIONS
OF THE EASTERN WV PANHANDLE AS WELL AS PORTIONS OF NORTH-CENTRAL WV.
OTHER STORMS HAD DEVELOPED ACROSS PORTIONS OF EASTERN KENTUCKY AND
THE WV MOUNTAIN COUNTIES.
THE COLD FRONT SHOULD EAST INTO THE REGION TONIGHT. MODELS
INDICATE AN UPPER LEVEL TROF WILL DEEPEN JUST TO OUR WEST TONIGHT
WITH MOST OF THE MODELS INDICATING AN UPPER LOW WILL DEVELOP. THE
NAM IS THE QUICKEST DEVELOPING A CLOSED LOW TO OUR SOUTHWEST AS
EARLY AS 12 UTC TUESDAY.
EXPECT SHOWER AND STORM CHANCES WILL INCREASE ACROSS THE
MOUNTAINS AND ACROSS PORTIONS OF SOUTHEAST OHIO...NORTHEAST
KENTUCKY AND THE SOUTHERN COALFIELDS THRU THE LATE EVENING HOURS.
IN RESPONSE TO THE COLD FRONT AND THE UPPER TROF...PRECIPITATION
CHANCES SHOULD THEN DEVELOP ACROSS MUCH OF THE REGION TONIGHT.
AS UPPER LEVEL TROF/LOW DRIFTS EAST ON TUESDAY...ALL OF THE MODELS
AS WELL AS HPC 6-HR QPF PRODUCT INDICATE MEASURABLE RAIN WILL BE A
GOOD BET ACROSS THE MOUNTAIN COUNTIES AND THE ADJACENT COUNTIES BY
TUESDAY AFTERNOON.
USED A BLEND OF MET/MAV GUIDANCE FOR LOWS TONIGHT. TEMP GUIDANCE
IS QUITE DIFFERENT FOR HIGHS ON TUESDAY...WITH THE DISCREPANCY A
DIFFERENCE OF 9 DEGREES AT KCRW. BECAUSE OF CLOUDS AND PRECIP...
WENT CLOSER TO THE COOLER MET NUMBERS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH S/W TROF
PROGRESSION AND PLACEMENT OF SUBSEQUENT CLOSING OFF OF H5 LOW
HEADING INTO MIDWEEK. GENERAL CONSENSUS PLACES UPR LOW OVER SOUTHERN
APPALACHIANS TUES NIGHT...REMAINING QUASI STATIONARY OVER THE AREA
AS IT BECOMES DETACHED FROM WESTERLIES. CLOSER TO SFC...WILL FOLLOW
BAROCLINIC ZONE AS IT STALLS OUT OVER THE AREA TUES AND QUICKLY
BECOMES RATHER DIFFUSE IN NATURE...LEAVING A SFC TROF IN ITS PLACE. THIS
IN COMBINATION WITH S/W TROF/UPR LOW WILL SERVE AS THE FOCUS FOR
SHRA/TSRA AT LEAST EARLY ON. TRIED TO ALLOW FOR A DIURNAL NATURE TO
THE POPS...ESPECIALLY FOR WED AND THU. ALLOWED FOR LKLY POPS TUES
AFTN AND AGAIN WED AFTN ACROSS THE MTNS ALBEIT WITH MARGINAL
INSOLATION TO BOOST...WITH HIGH CHC REMAINDER OF WV ZONES. APPEARS
SE OH/NE KY WILL STAY ON WESTERN FRINGE OF AFFECTS OF UPR LOW ONCE
INTO WED...WITH JUST SCHC POPS. UPR RIDGING BEGINS TO TAKE HOLD
THU WITH UPR LOW WEAKENING AND FILLING IN AS IT TRIES TO HEAD OFF
TO NE. STILL CARRIED SOME LOW CHC POPS WITH AFTN HEATING ON THU
ACROSS WV/SW VA. SHRA/TSRA THAT FORM WILL BE SLOW MOVERS TUES AND
WED. INTERESTING TO SEE RATHER LOW QPF AMNTS OFF MODELS
CONSIDERING VERY WEAK FLOW THRU H5 AND RATHER SATURATED SOUNDINGS.
MODELS MAY BE KEYING ON LACK OF OVERALL H85 MOISTURE TRANSPORT
WITH NO LLVL JET SUPPORT AMID TRANSPORT VECTORS GENERALLY FROM
NW...WITH PW STAYING MANAGEABLE. WILL KEEP WATER HIGHLIGHT IN RWS
FOR NOW THOUGH. ABUNDANCE OF CLDS WILL HOLD TEMPS DOWN TUE
EVERYWHERE...WITH SE OH/NE KY DOING BETTER WED THAN FURTHER EAST.
EVERYONE RECOVERS NICELY ON THU WITH MID 80S COMMON PLACE OUTSIDE
OF MTNS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
VFR CONDITIONS CAN BE EXPECTED AT MOST LOCATIONS THRU 03Z. THE
EXCEPTIONS WILL BE IN SHOWERS AND THUNDERSTORMS...WHERE IFR
CONDITIONS ARE POSSIBLE IN HEAVIER RAIN.
A COLD FRONT AND A DEVELOPING UPPER LEVEL FEATURE WILL AID IN THE
DEVELOPMENT OF CONVECTION LATE IN THE DAY...AND ENABLE THE
CONVECTION TO CONTINUE THROUGH 12Z. AREAS THAT RECEIVE RAINFALL
THIS AFTERNOON AND EVENING MAY HAVE FOG TONIGHT.
PRECIPITATION CHANCES WILL INCREASE BETWEEN 12Z AND 18Z ON TUESDAY
AS THE UPPER LEVEL FEATURE BEGINS TO DRIFT EAST. THE BEST CHANCES
FOR SHOWERS AND THUNDERSTORMS WILL BE ACROSS THE MOUNTAINS AND
ADJACENT COUNTIES...WHERE MVFR CONDITIONS ARE EXPECTED. ISOLATED
IFR CONDITIONS ARE POSSIBLE IN THE HEAVIER STORMS. ACROSS THE
REMAINDER OF THE REGION...VFR CONDITIONS ARE ANTICIPATED.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH 03Z TUESDAY...THEN MEDIUM 03Z
THRU 18Z.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND STORMS THROUGH TUESDAY
MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS INTO WEDNESDAY...ESPECIALLY IN
THE MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/KTB
NEAR TERM...JSH
SHORT TERM...30
LONG TERM...TRM
AVIATION...JSH
000
FXUS61 KRLX 211727
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
127 PM EDT MON MAY 21 2012
.SYNOPSIS...
COLD FRONT ARRIVES TONIGHT AND THEN WASHES OUT...AS AN UPPER
LEVEL SYSTEM DRIFTS BY...JUST TO OUR SOUTH. HIGH PRESSURE WILL
THEN RESULT IN VERY WARM WEATHER FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
LATEST SURFACE MAP SHOWS A WEAK COLD FRONT WAS LOCATED JUST TO OUR
WEST. A WEAK AREA OF LOW PRESSURE WAS ALSO TO OUR EAST. THIS
FEATURE WAS RESPONSIBLE FOR CLOUDS AND SPRINKLES ACROSS PORTIONS
OF THE EASTERN WV PANHANDLE AS WELL AS PORTIONS OF NORTH-CENTRAL WV.
OTHER STORMS HAD DEVELOPED ACROSS PORTIONS OF EASTERN KENTUCKY AND
THE WV MOUNTAIN COUNTIES.
THE COLD FRONT SHOULD EAST INTO THE REGION TONIGHT. MODELS
INDICATE AN UPPER LEVEL TROF WILL DEEPEN JUST TO OUR WEST TONIGHT
WITH MOST OF THE MODELS INDICATING AN UPPER LOW WILL DEVELOP. THE
NAM IS THE QUICKEST DEVELOPING A CLOSED LOW TO OUR SOUTHWEST AS
EARLY AS 12 UTC TUESDAY.
EXPECT SHOWER AND STORM CHANCES WILL INCREASE ACROSS THE
MOUNTAINS AND ACROSS PORTIONS OF SOUTHEAST OHIO...NORTHEAST
KENTUCKY AND THE SOUTHERN COALFIELDS THRU THE LATE EVENING HOURS.
IN RESPONSE TO THE COLD FRONT AND THE UPPER TROF...PRECIPITATION
CHANCES SHOULD THEN DEVELOP ACROSS MUCH OF THE REGION TONIGHT.
AS UPPER LEVEL TROF/LOW DRIFTS EAST ON TUESDAY...ALL OF THE MODELS
AS WELL AS HPC 6-HR QPF PRODUCT INDICATE MEASURABLE RAIN WILL BE A
GOOD BET ACROSS THE MOUNTAIN COUNTIES AND THE ADJACENT COUNTIES BY
TUESDAY AFTERNOON.
USED A BLEND OF MET/MAV GUIDANCE FOR LOWS TONIGHT. TEMP GUIDANCE
IS QUITE DIFFERENT FOR HIGHS ON TUESDAY...WITH THE DISCREPANCY A
DIFFERENCE OF 9 DEGREES AT KCRW. BECAUSE OF CLOUDS AND PRECIP...
WENT CLOSER TO THE COOLER MET NUMBERS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH S/W TROF
PROGRESSION AND PLACEMENT OF SUBSEQUENT CLOSING OFF OF H5 LOW
HEADING INTO MIDWEEK. GENERAL CONSENSUS PLACES UPR LOW OVER SOUTHERN
APPALACHIANS TUES NIGHT...REMAINING QUASI STATIONARY OVER THE AREA
AS IT BECOMES DETACHED FROM WESTERLIES. CLOSER TO SFC...WILL FOLLOW
BAROCLINIC ZONE AS IT STALLS OUT OVER THE AREA TUES AND QUICKLY
BECOMES RATHER DIFFUSE IN NATURE...LEAVING A SFC TROF IN ITS PLACE. THIS
IN COMBINATION WITH S/W TROF/UPR LOW WILL SERVE AS THE FOCUS FOR
SHRA/TSRA AT LEAST EARLY ON. TRIED TO ALLOW FOR A DIURNAL NATURE TO
THE POPS...ESPECIALLY FOR WED AND THU. ALLOWED FOR LKLY POPS TUES
AFTN AND AGAIN WED AFTN ACROSS THE MTNS ALBEIT WITH MARGINAL
INSOLATION TO BOOST...WITH HIGH CHC REMAINDER OF WV ZONES. APPEARS
SE OH/NE KY WILL STAY ON WESTERN FRINGE OF AFFECTS OF UPR LOW ONCE
INTO WED...WITH JUST SCHC POPS. UPR RIDGING BEGINS TO TAKE HOLD
THU WITH UPR LOW WEAKENING AND FILLING IN AS IT TRIES TO HEAD OFF
TO NE. STILL CARRIED SOME LOW CHC POPS WITH AFTN HEATING ON THU
ACROSS WV/SW VA. SHRA/TSRA THAT FORM WILL BE SLOW MOVERS TUES AND
WED. INTERESTING TO SEE RATHER LOW QPF AMNTS OFF MODELS
CONSIDERING VERY WEAK FLOW THRU H5 AND RATHER SATURATED SOUNDINGS.
MODELS MAY BE KEYING ON LACK OF OVERALL H85 MOISTURE TRANSPORT
WITH NO LLVL JET SUPPORT AMID TRANSPORT VECTORS GENERALLY FROM
NW...WITH PW STAYING MANAGEABLE. WILL KEEP WATER HIGHLIGHT IN RWS
FOR NOW THOUGH. ABUNDANCE OF CLDS WILL HOLD TEMPS DOWN TUE
EVERYWHERE...WITH SE OH/NE KY DOING BETTER WED THAN FURTHER EAST.
EVERYONE RECOVERS NICELY ON THU WITH MID 80S COMMON PLACE OUTSIDE
OF MTNS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
VFR CONDITIONS CAN BE EXPECTED AT MOST LOCATIONS THRU 03Z. THE
EXCEPTIONS WILL BE IN SHOWERS AND THUNDERSTORMS...WHERE IFR
CONDITIONS ARE POSSIBLE IN HEAVIER RAIN.
A COLD FRONT AND A DEVELOPING UPPER LEVEL FEATURE WILL AID IN THE
DEVELOPMENT OF CONVECTION LATE IN THE DAY...AND ENABLE THE
CONVECTION TO CONTINUE THROUGH 12Z. AREAS THAT RECEIVE RAINFALL
THIS AFTERNOON AND EVENING MAY HAVE FOG TONIGHT.
PRECIPITATION CHANCES WILL INCREASE BETWEEN 12Z AND 18Z ON TUESDAY
AS THE UPPER LEVEL FEATURE BEGINS TO DRIFT EAST. THE BEST CHANCES
FOR SHOWERS AND THUNDERSTORMS WILL BE ACROSS THE MOUNTAINS AND
ADJACENT COUNTIES...WHERE MVFR CONDITIONS ARE EXPECTED. ISOLATED
IFR CONDITIONS ARE POSSIBLE IN THE HEAVIER STORMS. ACROSS THE
REMAINDER OF THE REGION...VFR CONDITIONS ARE ANTICIPATED.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH 03Z TUESDAY...THEN MEDIUM 03Z
THRU 18Z.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND STORMS THROUGH TUESDAY
MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS INTO WEDNESDAY...ESPECIALLY IN
THE MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/KTB
NEAR TERM...JSH
SHORT TERM...30
LONG TERM...TRM
AVIATION...JSH
000
FXUS61 KRLX 211507
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1107 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST TODAY. COLD FRONT ARRIVES
TONIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL SYSTEM DRIFTS
SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
FORECAST IS GENERALLY ON TRACK. ONLY MADE TWEAKS TO SKY AS WELL
AS HOURLY TEMPS AND DEWPOINT TEMPS. OTHERWISE...LOOKS GOOD.
PREVIOUS DISCUSSION...
MODELS ARE FAIRLY CONSISTENT FOR TODAY AND TONIGHT. AREA IS IN A
SQUEEZE PLAY BETWEEN AN ATLANTIC SYSTEM AND AN APPROACHING COLD
FRONT WITH AN ASSOCIATED UPPER LOW TO THE WEST. WILL JUST MAKE
SOME MINOR TWEAKS TO THE CURRENT PACKAGE FOR TODAY...INCLUDING
TIGHTENING UP SOME POP GRADIENTS.
MODELS HAVE NOW TRANSITIONED MORE TOWARD PREVIOUS ECMWF SOLUTIONS
FOR MONDAY NIGHT. THIS PROVIDES FOR SLOWER MOVEMENT OF THE COLD
FRONT AND UPPER LOW ACROSS THE REGION. WILL SLOW THE POPS DOWN
ACCORDINGLY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH S/W TROF
PROGRESSION AND PLACEMENT OF SUBSEQUENT CLOSING OFF OF H5 LOW
HEADING INTO MIDWEEK. GENERAL CONSENSUS PLACES UPR LOW OVER SOUTHERN
APPALACHIANS TUES NIGHT...REMAINING QUASI STATIONARY OVER THE AREA
AS IT BECOMES DETACHED FROM WESTERLIES. CLOSER TO SFC...WILL FOLLOW
BAROCLINIC ZONE AS IT STALLS OUT OVER THE AREA TUES AND QUICKLY
BECOMES RATHER DIFFUSE IN NATURE...LEAVING A SFC TROF IN ITS PLACE. THIS
IN COMBINATION WITH S/W TROF/UPR LOW WILL SERVE AS THE FOCUS FOR
SHRA/TSRA AT LEAST EARLY ON. TRIED TO ALLOW FOR A DIURNAL NATURE TO
THE POPS...ESPECIALLY FOR WED AND THU. ALLOWED FOR LKLY POPS TUES
AFTN AND AGAIN WED AFTN ACROSS THE MTNS ALBEIT WITH MARGINAL
INSOLATION TO BOOST...WITH HIGH CHC REMAINDER OF WV ZONES. APPEARS
SE OH/NE KY WILL STAY ON WESTERN FRINGE OF AFFECTS OF UPR LOW ONCE
INTO WED...WITH JUST SCHC POPS. UPR RIDGING BEGINS TO TAKE HOLD
THU WITH UPR LOW WEAKENING AND FILLING IN AS IT TRIES TO HEAD OFF
TO NE. STILL CARRIED SOME LOW CHC POPS WITH AFTN HEATING ON THU
ACROSS WV/SW VA. SHRA/TSRA THAT FORM WILL BE SLOW MOVERS TUES AND
WED. INTERESTING TO SEE RATHER LOW QPF AMNTS OFF MODELS
CONSIDERING VERY WEAK FLOW THRU H5 AND RATHER SATURATED SOUNDINGS.
MODELS MAY BE KEYING ON LACK OF OVERALL H85 MOISTURE TRANSPORT
WITH NO LLVL JET SUPPORT AMID TRANSPORT VECTORS GENERALLY FROM
NW...WITH PW STAYING MANAGEABLE. WILL KEEP WATER HIGHLIGHT IN RWS
FOR NOW THOUGH. ABUNDANCE OF CLDS WILL HOLD TEMPS DOWN TUE
EVERYWHERE...WITH SE OH/NE KY DOING BETTER WED THAN FURTHER EAST.
EVERYONE RECOVERS NICELY ON THU WITH MID 80S COMMON PLACE OUTSIDE
OF MTNS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS CAN BE EXPECTED TODAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID AFTERNOON MONDAY...MEDIUM LATE
MONDAY AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND STORMS THIS AND TONIGHT
MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY L L L L L L H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...JSH/RPY
SHORT TERM...30
LONG TERM...TRM
AVIATION...
000
FXUS61 KRLX 211017
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
609 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST MONDAY. COLD FRONT ARRIVES
MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL SYSTEM DRIFTS
SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MODELS ARE FAIRLY CONSISTENT FOR TODAY AND TONIGHT. AREA IS IN A
SQUEEZE PLAY BETWEEN AN ATLANTIC SYSTEM AND AN APPROACHING COLD
FRONT WITH AN ASSOCIATED UPPER LOW TO THE WEST. WILL JUST MAKE SOME
MINOR TWEAKS TO THE CURRENT PACKAGE FOR TODAY...INCLUDING TIGHTENING
UP SOME POP GRADIENTS.
MODELS HAVE NOW TRANSITIONED MORE TOWARD PREVIOUS ECMWF SOLUTIONS
FOR MONDAY NIGHT. THIS PROVIDES FOR SLOWER MOVEMENT OF THE COLD
FRONT AND UPPER LOW ACROSS THE REGION. WILL SLOW THE POPS DOWN
ACCORDINGLY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH S/W TROF
PROGRESSION AND PLACEMENT OF SUBSEQUENT CLOSING OFF OF H5 LOW
HEADING INTO MIDWEEK. GENERAL CONSENSUS PLACES UPR LOW OVER SOUTHERN
APPALACHIANS TUES NIGHT...REMAINING QUASI STATIONARY OVER THE AREA
AS IT BECOMES DETACHED FROM WESTERLIES. CLOSER TO SFC...WILL FOLLOW
BAROCLINIC ZONE AS IT STALLS OUT OVER THE AREA TUES AND QUICKLY
BECOMES RATHER DIFFUSE IN NATURE...LEAVING A SFC TROF IN ITS PLACE. THIS
IN COMBINATION WITH S/W TROF/UPR LOW WILL SERVE AS THE FOCUS FOR
SHRA/TSRA AT LEAST EARLY ON. TRIED TO ALLOW FOR A DIURNAL NATURE TO
THE POPS...ESPECIALLY FOR WED AND THU. ALLOWED FOR LKLY POPS TUES
AFTN AND AGAIN WED AFTN ACROSS THE MTNS ALBEIT WITH MARGINAL
INSOLATION TO BOOST...WITH HIGH CHC REMAINDER OF WV ZONES. APPEARS
SE OH/NE KY WILL STAY ON WESTERN FRINGE OF AFFECTS OF UPR LOW ONCE
INTO WED...WITH JUST SCHC POPS. UPR RIDGING BEGINS TO TAKE HOLD
THU WITH UPR LOW WEAKENING AND FILLING IN AS IT TRIES TO HEAD OFF
TO NE. STILL CARRIED SOME LOW CHC POPS WITH AFTN HEATING ON THU
ACROSS WV/SW VA. SHRA/TSRA THAT FORM WILL BE SLOW MOVERS TUES AND
WED. INTERESTING TO SEE RATHER LOW QPF AMNTS OFF MODELS
CONSIDERING VERY WEAK FLOW THRU H5 AND RATHER SATURATED SOUNDINGS.
MODELS MAY BE KEYING ON LACK OF OVERALL H85 MOISTURE TRANSPORT
WITH NO LLVL JET SUPPORT AMID TRANSPORT VECTORS GENERALLY FROM
NW...WITH PW STAYING MANAGEABLE. WILL KEEP WATER HIGHLIGHT IN RWS
FOR NOW THOUGH. ABUNDANCE OF CLDS WILL HOLD TEMPS DOWN TUE
EVERYWHERE...WITH SE OH/NE KY DOING BETTER WED THAN FURTHER EAST.
EVERYONE RECOVERS NICELY ON THU WITH MID 80S COMMON PLACE OUTSIDE
OF MTNS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS CAN BE EXPECTED TODAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID AFTERNOON MONDAY...MEDIUM LATE
MONDAY AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND STORMS THIS AND TONIGHT
MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY M H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H L L L L L L L H H H
PKB CONSISTENCY M H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...RPY
SHORT TERM...30
LONG TERM...TRM
AVIATION...RPY
000
FXUS61 KRLX 210724
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
324 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST MONDAY. COLD FRONT ARRIVES
MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL SYSTEM DRIFTS
SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MODELS ARE FAIRLY CONSISTENT FOR TODAY AND TONIGHT. AREA IS IN A
SQUEEZE PLAY BETWEEN AN ATLANTIC SYSTEM AND AN APPROACHING COLD
FRONT WITH AN ASSOCIATED UPPER LOW TO THE WEST. WILL JUST MAKE SOME
MINOR TWEAKS TO THE CURRENT PACKAGE FOR TODAY...INCLUDING TIGHTENING
UP SOME POP GRADIENTS.
MODELS HAVE NOW TRANSITIONED MORE TOWARD PREVIOUS ECMWF SOLUTIONS
FOR MONDAY NIGHT. THIS PROVIDES FOR SLOWER MOVEMENT OF THE COLD
FRONT AND UPPER LOW ACROSS THE REGION. WILL SLOW THE POPS DOWN
ACCORDINGLY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH S/W TROF
PROGRESSION AND PLACEMENT OF SUBSEQUENT CLOSING OFF OF H5 LOW
HEADING INTO MIDWEEK. GENERAL CONSENSUS PLACES UPR LOW OVER SOUTHERN
APPALACHIANS TUES NIGHT...REMAINING QUASI STATIONARY OVER THE AREA
AS IT BECOMES DETACHED FROM WESTERLIES. CLOSER TO SFC...WILL FOLLOW
BAROCLINIC ZONE AS IT STALLS OUT OVER THE AREA TUES AND QUICKLY
BECOMES RATHER DIFFUSE IN NATURE...LEAVING A SFC TROF IN ITS PLACE. THIS
IN COMBINATION WITH S/W TROF/UPR LOW WILL SERVE AS THE FOCUS FOR
SHRA/TSRA AT LEAST EARLY ON. TRIED TO ALLOW FOR A DIURNAL NATURE TO
THE POPS...ESPECIALLY FOR WED AND THU. ALLOWED FOR LKLY POPS TUES
AFTN AND AGAIN WED AFTN ACROSS THE MTNS ALBEIT WITH MARGINAL
INSOLATION TO BOOST...WITH HIGH CHC REMAINDER OF WV ZONES. APPEARS
SE OH/NE KY WILL STAY ON WESTERN FRINGE OF AFFECTS OF UPR LOW ONCE
INTO WED...WITH JUST SCHC POPS. UPR RIDGING BEGINS TO TAKE HOLD
THU WITH UPR LOW WEAKENING AND FILLING IN AS IT TRIES TO HEAD OFF
TO NE. STILL CARRIED SOME LOW CHC POPS WITH AFTN HEATING ON THU
ACROSS WV/SW VA. SHRA/TSRA THAT FORM WILL BE SLOW MOVERS TUES AND
WED. INTERESTING TO SEE RATHER LOW QPF AMNTS OFF MODELS
CONSIDERING VERY WEAK FLOW THRU H5 AND RATHER SATURATED SOUNDINGS.
MODELS MAY BE KEYING ON LACK OF OVERALL H85 MOISTURE TRANSPORT
WITH NO LLVL JET SUPPORT AMID TRANSPORT VECTORS GENERALLY FROM
NW...WITH PW STAYING MANAGABLE. WILL KEEP WATER HIGHLIGHT IN RWS
FOR NOW THOUGH. ABUNDANCE OF CLDS WILL HOLD TEMPS DOWN TUE
EVERYWHERE...WITH SE OH/NE KY DOING BETTER WED THAN FURTHER EAST.
EVERYONE RECOVERS NICELY ON THU WITH MID 80S COMMON PLACE OUTSIDE
OF MTNS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
SOME MVFR FOG IS POSSIBLE IN RIVER VALLEYS EARLY THIS
MORNING...ESPECIALLY IN THE SOUTHERN AND WESTERN COUNTIES. VFR
CONDITIONS CAN BE EXPECTED MONDAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG MONDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID DAY MONDAY...MEDIUM MONDAY
AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG MAY VARY. TIMING OF
SHOWERS AND STORMS ON MONDAY AFTERNOON AND MONDAY NIGHT MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY H H M H H H H H H H H H
HTS CONSISTENCY H H H H L H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H M M M H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...RPY
SHORT TERM...30
LONG TERM...TRM
AVIATION...RPY
000
FXUS61 KRLX 210645
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
238 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST MONDAY. COLD FRONT ARRIVES
MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL SYSTEM DRIFTS
SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MODELS ARE FAIRLY CONSISTENT FOR TODAY AND TONIGHT. AREA IS IN A
SQUEEZE PLAY BETWEEN AN ATLANTIC SYSTEM AND AN APPROACHING COLD
FRONT WITH AN ASSOCIATED UPPER LOW TO THE WEST. WILL JUST MAKE SOME
MINOR TWEAKS TO THE CURRENT PACKAGE FOR TODAY...INCLUDING TIGHTENING
UP SOME POP GRADIENTS.
MODELS HAVE NOW TRANSITIONED MORE TOWARD PREVIOUS ECMWF SOLUTIONS
FOR MONDAY NIGHT. THIS PROVIDES FOR SLOWER MOVEMENT OF THE COLD
FRONT AND UPPER LOW ACROSS THE REGION. WILL SLOW THE POPS DOWN
ACCORDINGLY.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
SOME MVFR FOG IS POSSIBLE IN RIVER VALLEYS EARLY THIS
MORNING...ESPECIALLY IN THE SOUTHERN AND WESTERN COUNTIES. VFR
CONDITIONS CAN BE EXPECTED MONDAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG MONDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID DAY MONDAY...MEDIUM MONDAY
AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG MAY VARY. TIMING OF
SHOWERS AND STORMS ON MONDAY AFTERNOON AND MONDAY NIGHT MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H M H H H H H H H
HTS CONSISTENCY H H H M M M H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY
NEAR TERM...RPY
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...RPY
000
FXUS61 KRLX 210536
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
121 AM EDT MON MAY 21 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
1030 PM UPDATE...NO SIGNIFICANT CHANGES MADE TO CURRENT FORECAST.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SOME MVFR FOG IS POSSIBLE IN RIVER VALLEYS EARLY THIS
MORNING...ESPECIALLY IN THE SOUTHERN AND WESTERN COUNTIES. VFR
CONDITIONS CAN BE EXPECTED MONDAY...WITH THE EXCEPTION OF ANY
CONVECTION THAT DEVELOPS. A COLD FRONT APPROACHING FROM THE WEST
WILL AID CONVECTION LATE IN THE DAY...AND ENABLE THE CONVECTION TO
CONTINUE MONDAY NIGHT. AREAS THAT RECEIVE RAINFALL THIS AFTERNOON
AND EVENING MAY HAVE FOG MONDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH MID DAY MONDAY...MEDIUM MONDAY
AFTERNOON AND MONDAY NIGHT.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG MAY VARY. TIMING OF
SHOWERS AND STORMS ON MONDAY AFTERNOON AND MONDAY NIGHT MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H M H H H H H H H
HTS CONSISTENCY H H H M M M H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS LATE MONDAY NIGHT THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...RPY
000
FXUS61 KRLX 210233
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1033 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
1030 PM UPDATE...NO SIGNIFICANT CHANGES MADE TO CURRENT FORECAST.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE VALID
PERIOD...WITH THE EXCEPTION OF POSSIBLE RIVER VALLEY FOG FOR A FEW
HOURS IN THE MORNING WHICH MAY RESULT IN MVFR VIS RESTRICTIONS
ROUGHLY BETWEEN 09Z-12Z. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP MAINLY AFTER 18Z MON AS AN UPPER LEVEL LOW RETROGRADES
TOWARDS THE AREA FROM THE EAST WHILE A SURFACE COLD FRONT APPROACHES
THE AREA FROM THE WEST.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. TIMING OF SHOWERS AND STORMS ON MONDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
EDT 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09
CRW CONSISTENCY H H H H H H H H M H H H
HTS CONSISTENCY H H H H H H H M M M H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H M M M H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY EVENING THROUGH TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...50
000
FXUS61 KRLX 202325 CCA
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
724 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
715 PM UPDATE...NO MAJOR CHANGES MADE TO ONGOING FORECAST. A COUPLE
OF SHOWERS WHICH HAVE FORMED OVER THE CENTRAL HIGH TERRAIN SHOULD
DISSIPATE OVER THE COURSE OF THE NEXT HOUR OR SO WITH THE LOSS OF
DAYTIME HEATING.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE VALID
PERIOD...WITH THE EXCEPTION OF POSSIBLE RIVER VALLEY FOG FOR A FEW
HOURS IN THE MORNING WHICH MAY RESULT IN MVFR VIS RESTRICTIONS
ROUGHLY BETWEEN 09Z-12Z. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP MAINLY AFTER 18Z MON AS AN UPPER LEVEL LOW RETROGRADES
TOWARDS THE AREA FROM THE EAST WHILE A SURFACE COLD FRONT APPROACHES
THE AREA FROM THE WEST.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. TIMING OF SHOWERS AND STORMS ON MONDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H H H H H H H H H M H
HTS CONSISTENCY H H H H H H H H H M M M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY EVENING THROUGH TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...50
000
FXUS61 KRLX 202324
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
724 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
715 PM UPDATE...NO MAJOR CHANGES MADE TO ONGOING FORECAST. A COUPLE
OF SHOWERS WHICH HAVE FORMED OVER THE CENTRAL HIGH TERRAIN SHOULD
DISSIPATE OVER THE COURSE OF THE NEXT HOUR OR SO WITH THE LOSS OF
DAYTIME HEATING.
PREVIOUS DISCUSSION...KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST
OVER THE CENTRAL MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED
HEAT SOURCE EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE VALID
PERIOD...WITH THE EXCEPTION OF POSSIBLE RIVER VALLEY FOG FOR A FEW
HOURS IN THE MORNING WHICH MAY RESULT IN MVFR VIS RESTRICTIONS
ROUGHLY BETWEEN 09Z-12Z. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP MAINLY AFTER 18Z MON AS AN UPPER LEVEL LOW RETROGRADES
TOWARDS THE AREA FROM THE EAST WHILE A SURFACE COLD FRONT APPROACHES
THE AREA FROM THE WEST.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. TIMING OF SHOWERS AND STORMS ON MONDAY MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 05/21/12
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H H H H H H H H H M H
HTS CONSISTENCY H H H H H H H H H M M M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z TUESDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY EVENING THROUGH TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...50/SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...50
000
FXUS61 KRLX 202030
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
430 PM EDT SUN MAY 20 2012
.SYNOPSIS...
LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT AND MONDAY. COLD
FRONT ARRIVES MONDAY NIGHT AND THEN WASHES OUT...AS AN UPPER LEVEL
SYSTEM DRIFTS SOUTH OF THE AREA. VERY WARM FOR THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST OVER THE CENTRAL
MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED HEAT SOURCE
EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL S/W TROF MOVES INTO THE AREA MON NT. IT THEN SPLITS UP
TUE...THE NORTHERN STREAM COMPONENT LIFTS NE INTO EASTERN CANADA
AND THEN MINORS OUT...WHILE THE SOUTHERN STREAM COMPONENT CLOSES
OFF OVER THE WESTERN CAROLINAS BY WED MORNING. ASSOCIATED COLD
FRONT ENTERING THE AREA MON EVE WASHES OUT OVER THE AREA AS THE
SYSTEM SPLITS UP...PRECLUDING MUCH OF A DEW POINT DROP. THERE IS
MUCH BETTER MODEL AGREEMENT ON THIS SCENARIO COMPARED WITH THE PAST
COUPLE OF DAYS.
MOIST UNSTABLE AXIS ARRIVING FROM THE W MON EVE...ALONG WITH SURFACE
TROUGH RIGHT OVER THE AREA...SPELLS GOOD CHANCE FOR THUNDERSTORMS.
CAPE VALUES CLOSE TO 2 KJ / KG IN THE AXIS EARLY ON DROP
OVERNIGHT...BUT PW VALUES REMAIN AROUND A BUCK AND A THIRD WITH MEAN
FLOW AROUND TEN KNOTS. AS THE SYSTEM SPLITS LATE MON NT AND
TUE...FORCING BECOMES LESS FOCUSED IF NOT DISORGANIZED...SO HARD TO
DETERMINE PLACEMENT AND MOVEMENT OF CLUSTERS IN WHAT BECOMES KING OF
A COL AREA BETWEEN THE SPLITTING SYSTEMS RIGHT ON THRU WED NT. SLOW
MOVEMENT COULD BE A CONCERN ESPECIALLY IF PW VALUES WIND UP HIGHER
THAN CURRENTLY FCST...BUT VALUES SHOULD ACTUALLY WANE A BIT THROUGH
WED NT.
USED MET OR BIAS CORRECTED MET ON LOWS EARLY ON AND BIAS CORRECTED
MOS TO ADJUST TEMPERATURES...MOSTLY SHRINKING DIURNAL RANGES A BIT
WITH APPRECIABLE CLOUD COVER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
MODELS HAVE COME IN MUCH BETTER AGREEMENT IN LIFTING UPPER LEVEL
SYSTEM OUT OF THE AREA THU THRU FRI. THIS DECREASES POPS AND ALLOWS
FOR RISING TEMPERATURES. HOWEVER...HIGH PRESSURE ALOFT IS FCST TO
BUILD TO THE SW OF THE AREA RATHER THAN OVERTOP. GIVEN AMPLIFIED
PATTERN AND TELECONNECTIONS...HPC KEEPS FRONT ASSOCIATED WITH NEW
S/W ENERGY DROPPING DOWN E SIDE OF RIDGE OVER NE UNITED STATES JUST
N OF THE AREA. HOWEVER...THE FRONT MAY BE CLOSE ENOUGH FOR THE
THUNDERSTORM POSSIBILITY NEXT WEEKEND...MAINLY SUN. PRECIPITATION
THROUGHOUT THE PERIOD WILL BE DIURNALLY DRIVEN TO A SIGNIFICANT
EXTENT.
BLENDED IN HPC FOR MOST TEMPERATURES THOUGH CONCERNED ABOUT LOWER
MEX NUMBERS...ESPECIALLY ON HIGHS...GIVEN UPPER HIGH NOT RIGHT OVER
THE AREA...AT LEAST FOR LONG.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS EXPECTED FOR THE PERIOD...OUTSIDE OF SOME
PATCHY MVFR RIVER VALLEY FOG DEVELOPING AFTER 09Z. ANY FOG THAT
DEVELOPS WILL BURN OFF BY 13Z FOR A RETURN OF VFR CONDITIONS AREA
WIDE. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER 18Z
MONDAY AS A COLD FRONT APPROACHES FROM THE WEST...AND AN UPPER LOW
APPROACHES FROM THE EAST. EXPECT GRADUALLY LOWERING/THICKENING OF
CIGS AFTER 12Z MONDAY AS THESE TWO SYSTEMS APPROACH...ALTHOUGH
CIGS WILL REMAIN ABOVE VFR.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. SHOWERS/STORMS ON MONDAY MAY DEVELOP QUICKER THAN
FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...SL
000
FXUS61 KRLX 201802
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
202 PM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
KEPT THE SLIGHT CHANCE OF SHOWERS IN THE FORECAST OVER THE CENTRAL
MOUNTAINS THIS AFTERNOON DUE TO UPSLOPE FLOW/ELEVATED HEAT SOURCE
EFFECTS.
OVERALL...MODELS ARE IN DECENT AGREEMENT IN THE NEAR TERM. UPPER
LOW ALONG VIRGINIA COAST WILL GRADUALLY ROTATE TOWARDS THE REGION
ON MONDAY...SPREADING PRECIPITATION INTO THE AREA FROM THE EAST.
IN ADDITION...A COLD FRONT WILL APPROACH AND MOVE INTO THE AREA
FROM THE WEST ON MONDAY...ALSO BRINGING A CHANCE OF SHOWERS AND
THUNDERSTORMS TO THE FORECAST MONDAY AFTERNOON AND NIGHT. OVERALL
TREND OF THE MODELS HAS BEEN TO SLOW THE PROGRESSION OF THE
FEATURES AND ASSOCIATED PRECIP INTO THE REGION...AND CONTINUED
THAT TREND. MAY EVEN BE A BIT OF A DELAY IN START OF PRECIP ANYWAY
AS MODELS CONTINUING TO INDICATE PLENTY OF DRY AIR IN PLACE MONDAY
AFTERNOON.
USED A BLEND OF MET/MAV FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS EXPECTED FOR THE PERIOD...OUTSIDE OF SOME
PATCHY MVFR RIVER VALLEY FOG DEVELOPING AFTER 09Z. ANY FOG THAT
DEVELOPS WILL BURN OFF BY 13Z FOR A RETURN OF VFR CONDITIONS AREA
WIDE. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER 18Z
MONDAY AS A COLD FRONT APPROACHES FROM THE WEST...AND AN UPPER LOW
APPROACHES FROM THE EAST. EXPECT GRADUALLY LOWERING/THICKENING OF
CIGS AFTER 12Z MONDAY AS THESE TWO SYSTEMS APPROACH...ALTHOUGH
CIGS WILL REMAIN ABOVE VFR.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY. SHOWERS/STORMS ON MONDAY MAY DEVELOP QUICKER THAN
FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...SL
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...SL
000
FXUS61 KRLX 201403
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1003 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE... NO SIGNIFICANT CHANGES AT THIS TIME.
PREVIOUS DISCUSSION BELOW...
LOOKS LIKE MUCH OF THE AREA WILL SQUEEZE ONE MORE GOOD WX
DAY. WITH AN ABUNDANCE OF DRY AIR WORKING INTO AREA ALOFT...THINK
MOST OF CU DEVELOPMENT WILL BE CONFINED TO MTNS WHERE AS IN PAST
COUPLE DAYS HAVE SOME SCHC POPS IN FOR AFTN ISO SHRA WITH WEAK ESE
UPSLOPE SFC FLOW AMID ELEVATED HEAT SOURCE. TEMPS SIMILAR TO
YESTERDAY...MAYBE A DEGREE IMPROVEMENT. SHOULD SEE SOMEWHAT LWR
DWPTS IN AFTN THAN PAST FEW DAYS...WITH WHAT MIXING THERE IS DRAGGING
DOWN EXTREMELY DRY AIR ALOFT.
WILL SEE LLVL MOISTURE BEGIN TO ADVECT W THRU VA PIEDMONT ON THE
OUTER PERIPHERAL OF UPR LOW/TS ALBERTO TONIGHT. EVENT THOUGH E FLOW
STRENGTHENS KEPT POPS OUT OF MTNS ONCE SUN GOES DOWN GIVEN AN
ABUNDANCE OF DRY AIR IN FRONT OF THIS. DID BRING IN LOW CHC POPS
ACROSS CENTRAL/NORTHERN MTNS BY 12Z WITH LLVL MOISTURE FINALLY
GETTING INTO MTNS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
RVR FG QUICKLY DISSIPATES BY 13Z FOR A RETURN TO VFR CONDITIONS.
ISO SHRA ACROSS CENTRAL MTNS 18-22Z WITH LOCALIZED MVFR VSBY IN
ANY SHRA. MOSTLY JUST CIRRUS TDY WITH CU DEVELOPMENT STAYING
MAINLY IN MTNS.
LLVL MOISTURE ADVECTS W INTO CENTRAL/NORTHERN MTNS FROM OUTER
PERIPHERAL OF UPR LOW/TS ALBERTO LATE TONIGHT AFTER 09Z. CIGS WILL
LWR INTO MVFR ACROSS EASTERN SLOPES OF MAINLY NORTHERN MTNS WITH
CHCS FOR SHRA INCREASING BY 12Z. ELSEWHERE...PATCHY MVFR RVR FG
AGAIN TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY L H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...SL/30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
000
FXUS61 KRLX 201023
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
623 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
600AM UPDATE...
NO CHANGES AT THIS TIME.
PREVIOUS DISCUSSION BELOW...
LOOKS LIKE MUCH OF THE AREA WILL SQUEEZE ONE MORE GOOD WX
DAY. WITH AN ABUNDANCE OF DRY AIR WORKING INTO AREA ALOFT...THINK
MOST OF CU DEVELOPMENT WILL BE CONFINED TO MTNS WHERE AS IN PAST
COUPLE DAYS HAVE SOME SCHC POPS IN FOR AFTN ISO SHRA WITH WEAK ESE
UPSLOPE SFC FLOW AMID ELEVATED HEAT SOURCE. TEMPS SIMILAR TO
YESTERDAY...MAYBE A DEGREE IMPROVEMENT. SHOULD SEE SOMEWHAT LWR
DWPTS IN AFTN THAN PAST FEW DAYS...WITH WHAT MIXING THERE IS DRAGGING
DOWN EXTREMELY DRY AIR ALOFT.
WILL SEE LLVL MOISTURE BEGIN TO ADVECT W THRU VA PIEDMONT ON THE
OUTER PERIPHERAL OF UPR LOW/TS ALBERTO TONIGHT. EVENT THOUGH E FLOW
STRENGTHENS KEPT POPS OUT OF MTNS ONCE SUN GOES DOWN GIVEN AN
ABUNDANCE OF DRY AIR IN FRONT OF THIS. DID BRING IN LOW CHC POPS
ACROSS CENTRAL/NORTHERN MTNS BY 12Z WITH LLVL MOISTURE FINALLY
GETTING INTO MTNS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
RVR FG QUICKLY DISSIPATES BY 13Z FOR A RETURN TO VFR CONDITIONS.
ISO SHRA ACROSS CENTRAL MTNS 18-22Z WITH LOCALIZED MVFR VSBY IN
ANY SHRA. MOSTLY JUST CIRRUS TDY WITH CU DEVELOPMENT STAYING
MAINLY IN MTNS.
LLVL MOISTURE ADVECTS W INTO CENTRAL/NORTHERN MTNS FROM OUTER
PERIPHERAL OF UPR LOW/TS ALBERTO LATE TONIGHT AFTER 09Z. CIGS WILL
LWR INTO MVFR ACROSS EASTERN SLOPES OF MAINLY NORTHERN MTNS WITH
CHCS FOR SHRA INCREASING BY 12Z. ELSEWHERE...PATCHY MVFR RVR FG
AGAIN TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY M L L H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY M H H H H H H H H H H H
PKB CONSISTENCY M H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
000
FXUS61 KRLX 200742
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
333 AM EDT SUN MAY 20 2012
.SYNOPSIS...
HIGH PRESSURE TODAY. LOW PRESSURE CLOSE BY TO THE EAST LATE TONIGHT
AND MONDAY. COLD FRONT MONDAY NIGHT AND TUESDAY. VERY WARM FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
LOOKS LIKE MUCH OF THE AREA WILL SQUEEZE ONE MORE GOOD WX
DAY. WITH AN ABUNDANCE OF DRY AIR WORKING INTO AREA ALOFT...THINK
MOST OF CU DEVELOPMENT WILL BE CONFINED TO MTNS WHERE AS IN PAST
COUPLE DAYS HAVE SOME SCHC POPS IN FOR AFTN ISO SHRA WITH WEAK ESE
UPSLOPE SFC FLOW AMID ELEVATED HEAT SOURCE. TEMPS SIMILAR TO
YESTERDAY...MAYBE A DEGREE IMPROVEMENT. SHOULD SEE SOMEWHAT LWR
DWPTS IN AFTN THAN PAST FEW DAYS...WITH WHAT MIXING THERE IS DRAGGING
DOWN EXTREMELY DRY AIR ALOFT.
WILL SEE LLVL MOISTURE BEGIN TO ADVECT W THRU VA PIEDMONT ON THE
OUTER PERIPHERAL OF UPR LOW/TS ALBERTO TONIGHT. EVENT THOUGH E FLOW
STRENGTHENS KEPT POPS OUT OF MTNS ONCE SUN GOES DOWN GIVEN AN
ABUNDANCE OF DRY AIR IN FRONT OF THIS. DID BRING IN LOW CHC POPS
ACROSS CENTRAL/NORTHERN MTNS BY 12Z WITH LLVL MOISTURE FINALLY
GETTING INTO MTNS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODELS ARE IN FAIRLY GOOD AGREEMENT ON MONDAY...WITH BEST CHANCES OF
SHOWERS OR THUNDERSTORMS IN THE MOUNTAINS. NAM/GFS AND CANADIAN THEN
PUSH A COLD FRONT THROUGH MONDAY NIGHT AND TUESDAY. ECMWF THROWS A
WRENCH INTO THE EQUATION BY CUTTING OFF THE 500 MB LOW OVER THE
REGION AND THEREFORE STALLING THE COLD FRONT OVER THE REGION. WILL
GO PREDOMINATELY WITH THE NAM/GFS AND CANADIAN...BUT WILL LEAVE SOME
SMALL POPS OVER THE REGION WITH RESPECT FOR THE ECMWF...AS IT HAS
BEEN VERY CONSISTENT WITH THE 500 MB LOW.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
FCST PROBLEM THIS PERIOD LIES IN DIFFERENCES IN WHETHER AN UPPER
LEVEL S/W TROUGH EXITS WED / GFS / OR REPLACES THE OLD UPPER LEVEL
LOW OVER THE MID ATLANTIC / ECMWF /. THE LATTER SOLN WOULD REQUIRE
CHANCE THUNDERSTORMS WITH A DIURNAL SIGNATURE THROUGH THE PD. HPC
LEANED TOWARD THE ECMWF / EC ENS MEAN EARLY ON...AND THEN ALLOWS THE
UPPER LEVEL LOW TO DRIFT E AS THE WEEKEND ARRIVES. THIS DRIES OUT
THE POPS LATE FRI AND STARTS THE WEEKEND DRY.
HIGHS WERE CLOSE TO HPC AND BETWEEN THE WARM / PROGRESSIVE / AND
COLD / UPPER LEVEL LOW / SOLUTIONS SO NO SIGNIFICANT CHANGE THERE. HPC
ACTUALLY WENT HIGHER THAN THE MEX FOR DAY 7...STAYED CLOSER TO THE
MEX. GUIDANCE WAS A BIT BETTER CONVERGED ON LOWS...NO MAJOR CHANGES
WITH FCST CLOSE TO HPC. DID BLEND IN HPC TO RAISE LOWS SAT
MORNING. OVERALL HAVE A WARMING TREND THROUGH THE PERIOD WITH A
GRADUAL DECREASE IN THE INFLUENCE OF THE UPPER LEVEL LOW.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
OVERALL VFR CONDITIONS THROUGH THE
PERIOD...WITH THE EXCEPTION OF SOME MVFR FOG AFTER 06Z IN TYPICAL
RIVER VALLEY LOCATIONS...IE KCRW...KHTS...KPKB. HAVE SOME IFR
TYGART VALLEY BY 10Z TO INCLUDE KEKN.
RVR FG QUICKLY DISSIPATES BY 13Z FOR A RETURN TO VFR CONDITIONS.
ISO SHRA ACROSS CENTRAL MTNS 18-22Z WITH LOCALIZED MVFR VSBY IN
ANY SHRA. MOSTLY JUST CIRRUS TDY WITH CU DEVELOPMENT STAYING
MAINLY IN MTNS.
LLVL MOISTURE ADVECTS W INTO CENTRAL/NORTHERN MTNS FROM OUTER
PERIPHERAL OF UPR LOW/TS ALBERTO LATE TONIGHT AFTER 09Z. CIGS WILL
LWR INTO MVFR ACROSS EASTERN SLOPES OF MAINLY NORTHERN MTNS WITH
CHCS FOR SHRA INCREASING BY 12Z. ELSEWHERE...PATCHY MVFR RVR FG
AGAIN TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF CATEGORY REDUCTIONS DUE
TO FOG MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 05/20/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H M H H H H H H
HTS CONSISTENCY H M M M M M H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H M L M H H H H H H
PKB CONSISTENCY H M M M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z MONDAY...
BRIEF IFR POSSIBLE IN THUNDERSTORMS MONDAY AFTERNOON THROUGH
TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...30
| 
