000
FXUS64 KJAN 200912
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
410 AM CDT MON MAY 20 2013
.SHORT TERM...TODAY THROUGH WEDNESDAY...SURFACE ANALYSIS HAS A RIDGE
NOSING WEST ALONG THE GULF COAST STATES AND A LOW CENTERED OVER THE
SOUTHERN PLAINS. THE PRESSURE GRADIENT BETWEEN THE TWO WAS
MAINTAINING A SOUTH TO SOUTHEAST WIND THAT WAS HELPING TO SPREAD A
LAYER OF STRATUS NORTHWARD AGAIN THIS EARLY MORNING AS SEEN ON
SATELLITE IMAGERY. TEMPERATURES WERE IN THE LOW TO MID 70S AND
ADDITIONAL COOLING WILL BE LIMITED BY THE STRATUS DECK. THUS...WL
START OFF WARMER THAN NORMAL THIS MORNING AND TOP OUT WARMER THAN
NORMAL THIS AFTERNOON. MODEL SOUNDINGS SUGGEST THE STRATUS WILL
DISSIPATE BY MID MORNING. WATER VAPOR IMAGERY/RUC ANALYSIS INDICATES
MID LEVEL RIDGING FROM THE WESTERN GULF ACROSS OUR CWA TO THE OHIO
VALLEY. RIDGING SURFACE AND ALOFT SHOULD HELP LIMIT CONVECTION
POTENTIAL TODAY AND THE EXPECTED INSOLATION SHOULD HELP TEMPS TOP
OUT NEAR 90 AT MANY LOCATIONS. THE RIDGING SURFACE AND ALOFT WILL
WEAKEN OVER OUR CWA TONIGHT BUT ANOTHER WARM AND HUMID NIGHT WITH
EARLY MORNING STRATUS IS EXPECTED.
COME TUESDAY MORNING A SHORTWAVE WILL BE TRACKING EAST ACROSS THE
SOUTHERN PLAINS...ROUNDING THE BASE OF AN UPPER TROUGH ASSOCIATED
WITH A NEARLY STACKED LOW OVER THE NORTHERN PLAINS. THE GFS AND
ECMWF ARE IN GOOD AGREEMENT WITH THE FORCING NOT ARRIVING UNTIL
AFTER MIDNIGHT TUESDAY NIGHT AND SHIFTING EAST OF OUR CWA BY
WEDNESDAY AFTERNOON. HOWEVER...BY TUESDAY AFTERNOON LOWER 70 DEGREE
DEW POINTS AND PWS ABOVE AN INCH AND A HALF WILL BE OVER THE
NORTHWEST HALF OF OUR CWA. TEMPERATURES IN THE UPPER 80S WILL
CONTRIBUTE TO MLCAPES AROUND 2500J/KG. DEEP LAYER SHEAR IS EXPECTED
TO BE LESS THAN 30KTS BUT MID LEVEL LAPSE RATES OF 7.5C/KM...LI OF
-10 AND VERTICAL TOTALS OF 29 WILL BE SUPPORTIVE OF LARGE HAIL WITH
THE STORMS THAT DEVELOP. WL CONTINUE MENTION OF SEVERE STORMS NW OF
THE NATCHEZ TRACE TUESDAY AFTERNOON AND EVENING IN THE HWO.
ADDITIONAL SEVERE STORM POTENTIAL WILL EXIST OVERNIGHT IN THE WEST
AND SHIFT TO THE EAST WEDNESDAY AS THE TROUGH AXIS SWINGS ACROSS THE
AREA. OVERALL...THE GREATEST CHANCE FOR SEVERE STORMS THROUGH THE
SHORT TERM IS EXPECTED OVER THE NORTHWEST HALF OF THE CWA TUESDAY
NIGHT. /22/
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...A WEAK FRONTAL
BOUNDARY WILL CONTINUE TO MOVE ACROSS THE ARKLAMISS ON WEDNESDAY
NIGHT AND THURSDAY. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL CONTINUE TO BE POSSIBLE...ESPECIALLY THURSDAY AFTERNOON. AS THE
UPPER TROUGH CONTINUES TO SHIFT EAST OF THE AREA A STRONGER BACKDOOR
COLD FRONT WILL DROP SOUTH ACROSS THE AREA EARLY ON FRIDAY AND THIS
MAY KICK OFF SOME ISOLATED THUNDERSTORM ACTIVITY ONCE AGAIN FRIDAY
AFTERNOON BEFORE MUCH DRIER AIR BUILDS IN FROM THE NORTHEAST FRIDAY
NIGHT INTO SATURDAY.
THE WEEKEND LOOKS MAINLY DRY ON SATURDAY AND SUNDAY AS HIGH PRESSURE
RIDGING BUILDS IN FROM A SURFACE HIGH OVER THE OHIO VALLEY AND PWATS
FALL WELL BE LOW AN INCH. THE DRIER AIR WILL RESULT IN LOWER RH`S ON
SATURDAY...BUT WILL STILL BE VERY WARM WITH HIGHS UP INTO THE MID
80S. THE SURFACE HIGH WILL SHIFT EAST AND THIS WILL ALLOW THE WINDS
TO BECOME MORE EASTERLY THAN SOUTHEASTERLY...BUT HIGH PRESSURE
RIDGING AND MAINLY DRY CONDITIONS LOOKS LIKE IT WILL CONTINUE
THROUGH MONDAY./15/
&&
.AVIATION...WIDESPREAD MVFR CEILINGS WERE BEING REPORTED AT 08Z AND
A BRIEF LOWERING TO IFR CATEGORY IS POSSIBLE 11Z-14Z...ESPECIALLY
ACROSS THE CENTRAL AND SOUTH. SOUNDINGS INDICATE THE STRATUS WILL
LIFT AND DISSIPATE BY 17Z. VFR CONDITIONS ARE THEN EXPECTED TO
PREVAIL THROUGH THIS EVENING. SE-S WINDS 10-14KTS WITH HIGHER GUSTS
CAN BE EXPECTED BY 17Z WITH STRONGEST WINDS OVER THE NW. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 90 68 89 68 / 2 5 25 30
MERIDIAN 90 65 90 65 / 2 3 17 14
VICKSBURG 90 71 88 69 / 3 9 30 40
HATTIESBURG 90 68 91 66 / 3 3 11 10
NATCHEZ 88 70 88 69 / 5 5 16 29
GREENVILLE 89 71 88 70 / 3 14 41 60
GREENWOOD 90 69 89 69 / 3 12 33 49
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
22/15/22
000
FXUS64 KJAN 200217 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
917 PM CDT SUN MAY 19 2013
.UPDATE...
OVERALL QUIET NIGHT TONIGHT AS SHORTWAVE RIDGING AND HIGH PRESSURE
WILL KEEP THE REGION DRY TONIGHT. THE STRONG UPPER TROUGH OVER THE
CENTRAL PLAINS WILL GRADUALLY PROPAGATE TO THE EAST AND SOME OF THE
CONVECTIVE HIGH CLOUDS WILL MOVE IN THE NORTHWESTERN AREAS OVERNIGHT
TONIGHT. HAD TO MODIFY SKY GRIDS AS MOST OF THE REGION HAS CLEARED
FROM CLOUDS FROM EARLIER AS SHORTWAVE RIDGE AXIS MOVES THROUGH THE
REGION. THERE WILL BE THE POTENTIAL FOR SOME LOW STRATUS/PATCHY FOG
DUE TO CAPPED LOW LEVEL MOISTURE...CLEAR SKIES AND LIGHT WINDS.
HOWEVER...LOW LEVEL FLOW PER MODEL SOUNDINGS LOOK STRONG ENOUGH TO
LIMIT FOG POTENTIAL AND FAVOR MORE STRATUS DEVELOPMENT. SREF PROBS
WERE REALLY HIGHLIGHTING AREAS ALONG AND SOUTH OF I-20 CORRIDOR FOR
LOW CLOUDS/PATCHY FOG. TEMPS OVERNIGHT LOOK GOOD. REST OF THE
FORECAST IS ON TRACK. /DC/
&&
.AVIATION...THE PRIMARY AVIATION CONCERN FOR LATER TONIGHT INTO
MONDAY MORNING WILL BE AN EPISODE OF MVFR/IFR CATEGORY STRATUS...AND
PERHAPS SOME FOG...IMPACTING MOST TAF SITES IN SOUTHERLY LOW-LEVEL
FLOW. EXPECT CEILINGS AND ANY FOG TO LIFT AND BREAK UP BY MID TO
LATE MONDAY MORNING WITH VFR CONDITIONS THEN PREVAILING THROUGH
MONDAY EVENING. /EC/
&&
.PREV DISCUSSION... /ISSUED 325 PM CDT SUN MAY 19 2013/
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT...
THE PRIMARY CONCERNS WILL BE THE POTENTIAL FOR A FEW STRONG TO
SEVERE STORMS FOR TUESDAY AFTERNOON AND NIGHT WITH THE RISK OF
QUARTER SIZED HAIL...LOCALLY HEAVY RAINFALL AND SOME GUSTY WINDS. ALSO AN
ISOLATED STORM IN THE SOUTH HALF FOR THE REST OF THE AFTERNOON ALONG
WITH POPS AND TEMPS.
LATEST SATELLITE IMAGERY SHOWED THE REGION UNDER THE INFLUENCE OF A
SHORTWAVE RIDGE WITH WEAK MOISTURE CONVERGENCE...WHICH WAS BEING
FLANKED BY A STRONG UPPER TROUGH OVER THE PLAINS AND SHORT WAVE
TROUGHING OVER THE SOUTHEAST US. SKIES WERE PARTLY CLOUDY OVER THE REGION
FOR THIS AFTERNOON WITH HIGH DEBRIS CLOUDS COMING FROM THE PLAINS
STORM SYSTEM. SO FAR THE RADAR HAS BEEN CLEAR...BUT THERE IS STILL
THE SLIM CHANCE OF AN ISOLATED POSSIBLY STRONG STORM ACROSS THE
SOUTH HALF FOR THE REST OF THE AFTERNOON WITH INSTABILITY AND SOME
MOISTURE TRANSPORT IN PLACE.
FOR TONIGHT...THE UPPER PLAINS SYSTEM WILL CREEP SLOWLY TOWARD THE REGION
AS UPPER SHORT WAVE RIDGING AXIS MOVES EAST OF THE REGION BY EARLY
MONDAY. ONCE AGAIN LOW LEVEL BOUNDARY LAYER MOISTURE WILL INCREASE WITH
SOUTHERLY FLOW. THIS WILL ALLOW ANOTHER ROUND OF STRATUS ALONG WITH SOME
PATCHY SHALLOW FOG TO DEVELOP AFTER MIDNIGHT. BELIEVE THAT THE LOW
LEVEL FLOW WILL HINDER ANY SIGNIFICANT FOG DEVELOPMENT...DESPITE MODELS
FAVORING SOME FOG POTENTIAL. IT WILL BE ANOTHER MUGGY NIGHT WITH
LOWS FROM THE MID 60S TO AROUND 70. MOS AND MAV GUIDANCE LOOKED A
LITTLE COOL WITH THE LOW LEVEL BOUNDARY MOISTURE IN PLACE. SO WENT
WITH MILDER GFS GUIDANCE.
FOR MONDAY AND MONDAY NIGHT...THE STRATUS WILL LIFT BY LATE MORNING.
THE AXIS OF THE SOUTHERN PLAINS TROUGH WILL PUSH DOWN INTO THE
SOUTHERN PLAINS AS LOW LEVEL INFLOW INCREASES ACROSS THE REGION. THE
SPC WRF TRIES TO SHOW SOME CONVECTION ACROSS THE DELTA WHILE ALL THE
OTHER MODELS AND WRF GUIDANCE WERE GENERALLY CLEAR. THINK THAT THE
CAP WILL HINDER ANY DEVELOPMENT DURING THE DAY. PUT THE BEST LOW DRY
POPS IN THE WEST. FOR MONDAY NIGHT 500 MB HEIGHTS WILL START TO
GRADUALLY LOWER FROM THE NORTHWEST. PUT IN SLIGHT TEEN POPS FOR
CONVECTION IN THE NORTHWEST AFTER MIDNIGHT. JUST IN CASE THERE WOULD
BE AN OUTFLOW BOUNDARY COMING FROM THE STORMS TO THE NORTHWEST.
EXPECT ANOTHER ROUND OF STRATUS...BUT ONCE AGAIN THE LOW LEVEL FLOW
WILL HINDER ANY SIGNIFICANT FOG DEVELOPMENT AFTER MIDNIGHT...DESPITE
MODEL PROGS. HIGHS ON MONDAY WILL BE FROM THE UPPER 80S TO AROUND
90. LOWS WILL BE FROM THE MID 60S TO THE LOWER 70S. WENT WITH GMOS
GUIDANCE ON HIGHS AND ONCE AGAIN MILDER GFS GUIDANCE ON LOWS.
FOR TUESDAY AND TUESDAY NIGHT...500 MB HEIGHTS WILL DROP FROM THE
NORTHWEST DURING THE PERIOD AS THE UPPER TROUGH AXIS PUSHES TOWARD
THE LOWER MISSISSIPPI VALLEY REGION. OUR CHANCES OF CONVECTION WILL
GRADUALLY INCREASE ACROSS THE REGION DURING THE PERIOD. THERE WILL
BE ENOUGH INSTABILITY AND LIMITED JET DYNAMICS FOR A FEW STRONG TO
SEVERE STORMS FOR TUESDAY AFTERNOON AND NIGHT. PWATS WILL INCREASE
TO AROUND 1.7 INCHES(LOCALLY HEAVY RAINFALL). THE BULK SHEAR WILL
NOT BE IMPRESSIVE WITH THIS SYSTEM THROUGH MOST OF TUESDAY NIGHT. A
MIDLEVEL JET OF AROUND 50 KNOTS WILL MOVE ACROSS THE DELTA REGION
FOR TUESDAY NIGHT. CAPES WILL BE FROM 1500 TO 3500 J/KG...SHOWALTERS
-3 TO -7. AN MCS WILL MOVE ACROSS THE REGION DURING THE PERIOD FROM
THE NORTHWEST TUESDAY AFTERNOON AND NIGHT. SO AS FAR AS TEMPS ARE
CONCERN HIGHS WILL BE FROM THE MID TO UPPER 80S. LOWS WILL BE FROM
THE MID 60S TO AROUND 70S. WENT CLOSE TO GMOS GUIDANCE ON HIGHS AND
MILDER GFS GUIDANCE ON LOWS. FOR POPS WENT CLOSE TO MAV GUIDANCE./17/
/PREVIOUS DISCUSSION...
LONG TERM...WEDNESDAY THROUGH SUNDAY...THE WEAKENING UPPER LEVEL
TROUGH WILL SWING ACROSS OUR CWA WEDNESDAY BUT MODELS HAVE BACKED
OFF ON ANY FROPA IN OUR CWA AS THE FRONT FIZZLES NORTH OF OUR AREA.
OVERALL...THERMODYNAMIC PARAMETERS LOOK LESS FAVORABLE FOR SEVERE
WEATHER WEDNESDAY INTO THURSDAY BUT WL STILL HAVE A WARM MOIST
AIRMASS IN PLACE WITH RATHER STEEP MID LEVEL LAPSE RATES SO A FEW
STRONG STORMS WILL BE HARD TO RULE OUT. THE UPPER TROUGH AXIS WILL
BE EAST OF OUR CWA THURSDAY BUT NORTHWEST FLOW ALOFT WILL CONTINUE
OVER OUR CWA THROUGH SATURDAY. ALTHOUGH MOST OF THE CONVECTION WILL
SHOULD SHOW A DISTINCT DIURNAL TREND...MODELS INDICATE DISTURBANCES
ALOFT IN THE NW FLOW MAY SET OFF SOME CONVECTION OVER NIGHT THURSDAY
AND FRIDAY NIGHTS. IN ADDITION...BOTH GFS AND ECMWF SHOW A SURFACE
HIGH DROPPING OVER THE GREAT LAKES REGION FRIDAY NIGHT THAT MAY PUSH
A WEAK BACKDOOR COLD FRONT INTO OUR CWA SATURDAY. RIDGING SURFACE
AND ALOFT IS EXPECTED TO BUILD OVER OUR REGION SUNDAY RESULTING IN
DRY WEATHER. /22/17/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 68 90 67 89 / 5 10 7 10
MERIDIAN 67 92 66 90 / 5 8 6 8
VICKSBURG 70 89 71 89 / 5 11 8 15
HATTIESBURG 69 91 67 90 / 8 8 7 8
NATCHEZ 70 89 71 88 / 7 11 10 18
GREENVILLE 69 89 71 88 / 4 11 17 29
GREENWOOD 69 91 68 88 / 4 10 13 19
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/EC/17/22
000
FXUS64 KJAN 192031
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
325 PM CDT SUN MAY 19 2013
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT...
THE PRIMARY CONCERNS WILL BE THE POTENTIAL FOR A FEW STRONG TO
SEVERE STORMS FOR TUESDAY AFTERNOON AND NIGHT WITH THE RISK OF
QUARTER SIZED HAIL...LOCALLY HEAVY RAINFALL AND SOME GUSTY WINDS. ALSO AN
ISOLATED STORM IN THE SOUTH HALF FOR THE REST OF THE AFTERNOON ALONG
WITH POPS AND TEMPS.
LATEST SATELLITE IMAGERY SHOWED THE REGION UNDER THE INFLUENCE OF A
SHORTWAVE RIDGE WITH WEAK MOISTURE CONVERGENCE...WHICH WAS BEING
FLANKED BY A STRONG UPPER TROUGH OVER THE PLAINS AND SHORT WAVE
TROUGHING OVER THE SOUTHEAST US. SKIES WERE PARTLY CLOUDY OVER THE REGION
FOR THIS AFTERNOON WITH HIGH DEBRIS CLOUDS COMING FROM THE PLAINS
STORM SYSTEM. SO FAR THE RADAR HAS BEEN CLEAR...BUT THERE IS STILL
THE SLIM CHANCE OF AN ISOLATED POSSIBLY STRONG STORM ACROSS THE
SOUTH HALF FOR THE REST OF THE AFTERNOON WITH INSTABILITY AND SOME
MOISTURE TRANSPORT IN PLACE.
FOR TONIGHT...THE UPPER PLAINS SYSTEM WILL CREEP SLOWLY TOWARD THE REGION
AS UPPER SHORT WAVE RIDGING AXIS MOVES EAST OF THE REGION BY EARLY
MONDAY. ONCE AGAIN LOW LEVEL BOUNDARY LAYER MOISTURE WILL INCREASE WITH
SOUTHERLY FLOW. THIS WILL ALLOW ANOTHER ROUND OF STRATUS ALONG WITH SOME
PATCHY SHALLOW FOG TO DEVELOP AFTER MIDNIGHT. BELIEVE THAT THE LOW
LEVEL FLOW WILL HINDER ANY SIGNIFICANT FOG DEVELOPMENT...DESPITE MODELS
FAVORING SOME FOG POTENTIAL. IT WILL BE ANOTHER MUGGY NIGHT WITH
LOWS FROM THE MID 60S TO AROUND 70. MOS AND MAV GUIDANCE LOOKED A
LITTLE COOL WITH THE LOW LEVEL BOUNDARY MOISTURE IN PLACE. SO WENT
WITH MILDER GFS GUIDANCE.
FOR MONDAY AND MONDAY NIGHT...THE STRATUS WILL LIFT BY LATE MORNING.
THE AXIS OF THE SOUTHERN PLAINS TROUGH WILL PUSH DOWN INTO THE
SOUTHERN PLAINS AS LOW LEVEL INFLOW INCREASES ACROSS THE REGION. THE
SPC WRF TRIES TO SHOW SOME CONVECTION ACROSS THE DELTA WHILE ALL THE
OTHER MODELS AND WRF GUIDANCE WERE GENERALLY CLEAR. THINK THAT THE
CAP WILL HINDER ANY DEVELOPMENT DURING THE DAY. PUT THE BEST LOW DRY
POPS IN THE WEST. FOR MONDAY NIGHT 500 MB HEIGHTS WILL START TO
GRADUALLY LOWER FROM THE NORTHWEST. PUT IN SLIGHT TEEN POPS FOR
CONVECTION IN THE NORTHWEST AFTER MIDNIGHT. JUST IN CASE THERE WOULD
BE AN OUTFLOW BOUNDARY COMING FROM THE STORMS TO THE NORTHWEST.
EXPECT ANOTHER ROUND OF STRATUS...BUT ONCE AGAIN THE LOW LEVEL FLOW
WILL HINDER ANY SIGNIFICANT FOG DEVELOPMENT AFTER MIDNIGHT...DESPITE
MODEL PROGS. HIGHS ON MONDAY WILL BE FROM THE UPPER 80S TO AROUND
90. LOWS WILL BE FROM THE MID 60S TO THE LOWER 70S. WENT WITH GMOS
GUIDANCE ON HIGHS AND ONCE AGAIN MILDER GFS GUIDANCE ON LOWS.
FOR TUESDAY AND TUESDAY NIGHT...500 MB HEIGHTS WILL DROP FROM THE
NORTHWEST DURING THE PERIOD AS THE UPPER TROUGH AXIS PUSHES TOWARD
THE LOWER MISSISSIPPI VALLEY REGION. OUR CHANCES OF CONVECTION WILL
GRADUALLY INCREASE ACROSS THE REGION DURING THE PERIOD. THERE WILL
BE ENOUGH INSTABILITY AND LIMITED JET DYNAMICS FOR A FEW STRONG TO
SEVERE STORMS FOR TUESDAY AFTERNOON AND NIGHT. PWATS WILL INCREASE
TO AROUND 1.7 INCHES(LOCALLY HEAVY RAINFALL). THE BULK SHEAR WILL
NOT BE IMPRESSIVE WITH THIS SYSTEM THROUGH MOST OF TUESDAY NIGHT. A
MIDLEVEL JET OF AROUND 50 KNOTS WILL MOVE ACROSS THE DELTA REGION
FOR TUESDAY NIGHT. CAPES WILL BE FROM 1500 TO 3500 J/KG...SHOWALTERS
-3 TO -7. AN MCS WILL MOVE ACROSS THE REGION DURING THE PERIOD FROM
THE NORTHWEST TUESDAY AFTERNOON AND NIGHT. SO AS FAR AS TEMPS ARE
CONCERN HIGHS WILL BE FROM THE MID TO UPPER 80S. LOWS WILL BE FROM
THE MID 60S TO AROUND 70S. WENT CLOSE TO GMOS GUIDANCE ON HIGHS AND
MILDER GFS GUIDANCE ON LOWS. FOR POPS WENT CLOSE TO MAV GUIDANCE./17/
./PREVIOUS DISCUSSION...
.LONG TERM...WEDNESDAY THROUGH SUNDAY...THE WEAKENING UPPER LEVEL
TROUGH WILL SWING ACROSS OUR CWA WEDNESDAY BUT MODELS HAVE BACKED
OFF ON ANY FROPA IN OUR CWA AS THE FRONT FIZZLES NORTH OF OUR AREA.
OVERALL...THERMODYNAMIC PARAMETERS LOOK LESS FAVORABLE FOR SEVERE
WEATHER WEDNESDAY INTO THURSDAY BUT WL STILL HAVE A WARM MOIST
AIRMASS IN PLACE WITH RATHER STEEP MID LEVEL LAPSE RATES SO A FEW
STRONG STORMS WILL BE HARD TO RULE OUT. THE UPPER TROUGH AXIS WILL
BE EAST OF OUR CWA THURSDAY BUT NORTHWEST FLOW ALOFT WILL CONTINUE
OVER OUR CWA THROUGH SATURDAY. ALTHOUGH MOST OF THE CONVECTION WILL
SHOULD SHOW A DISTINCT DIURNAL TREND...MODELS INDICATE DISTURBANCES
ALOFT IN THE NW FLOW MAY SET OFF SOME CONVECTION OVER NIGHT THURSDAY
AND FRIDAY NIGHTS. IN ADDITION...BOTH GFS AND ECMWF SHOW A SURFACE
HIGH DROPPING OVER THE GREAT LAKES REGION FRIDAY NIGHT THAT MAY PUSH
A WEAK BACKDOOR COLD FRONT INTO OUR CWA SATURDAY. RIDGING SURFACE
AND ALOFT IS EXPECTED TO BUILD OVER OUR REGION SUNDAY RESULTING IN
DRY WEATHER. /22/17/
&&
.AVIATION...FEW TO SCATTERED CU ANTICIPATED THROUGH THE REMAINDER OF
THE AFTERNOON WITH BASES FROM 3 TO 5 KFT. WINDS WILL BE FROM THE
SOUTH AND GUSTY AT TIMES...PARTICULARLY IN THE DELTA. CONDITIONS
LATE THIS AFTERNOON THROUGH TOMORROW MORNING SHOULD BE QUITE SIMILAR
TO 24 HOURS AGO DUE TO PERSISTENT PATTERN. THUS...ANTICIPATE MIX OF
THE IFR/MVFR CEILINGS (BASES 800 TO 1500 FEET) DEVELOPING BETWEEN 3
AND 7 AM TOMORROW WITH NO DENSE FOG. CEILINGS WILL IMPROVE FROM 8 AM
THROUGH 10 AM...BUT MAY TAKE UNTIL NOON TO GO VFR IN ALL LOCATIONS.
/BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 68 90 67 89 / 10 10 7 10
MERIDIAN 67 92 66 90 / 10 8 6 8
VICKSBURG 70 89 71 89 / 10 11 8 15
HATTIESBURG 69 91 67 90 / 13 8 7 8
NATCHEZ 70 89 71 88 / 12 11 10 18
GREENVILLE 69 89 71 88 / 7 11 17 29
GREENWOOD 69 91 68 88 / 7 10 13 19
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
17/BB/22
000
FXUS64 KJAN 192024
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
325 PM CDT SUN MAY 19 2013
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT...
THE PRIMARY CONCERNS WILL BE THE POTENTIAL FOR A FEW STRONG TO
SEVERE STORMS FOR TUESDAY AFTERNOON AND NIGHT WITH THE RISK OF
QUARTER SIZED HAIL AND SOME GUSTY WINDS. ALSO AN ISOLATED STORM
IN THE SOUTH HALF FOR THE REST OF THE AFTERNOON ALONG WITH POPS AND
TEMPS.
LATEST SATELLITE IMAGERY SHOWED THE REGION UNDER THE INFLUENCE OF A
SHORTWAVE RIDGE WITH WEAK MOISTURE CONVERGENCE...WHICH WAS BEING
FLANKED BY A STRONG UPPER TROUGH OVER THE PLAINS AND SHORT WAVE
TROUGHING OVER THE SOUTHEAST US. SKIES WERE PARTLY CLOUDY OVER THE REGION
FOR THIS AFTERNOON WITH HIGH DEBRIS CLOUDS COMING FROM THE PLAINS
STORM SYSTEM. SO FAR THE RADAR HAS BEEN CLEAR...BUT THERE IS STILL
THE SLIM CHANCE OF AN ISOLATED POSSIBLY STRONG STORM ACROSS THE
SOUTH HALF FOR THE REST OF THE AFTERNOON WITH INSTABILITY AND SOME
MOISTURE TRANSPORT IN PLACE.
FOR TONIGHT...THE UPPER PLAINS SYSTEM WILL CREEP SLOWLY TOWARD THE REGION
AS UPPER SHORT WAVE RIDGING AXIS MOVES EAST OF THE REGION BY EARLY
MONDAY. ONCE AGAIN LOW LEVEL BOUNDARY LAYER MOISTURE WILL INCREASE WITH
SOUTHERLY FLOW. THIS WILL ALLOW ANOTHER ROUND OF STRATUS ALONG WITH SOME
PATCHY SHALLOW FOG TO DEVELOP AFTER MIDNIGHT. BELIEVE THAT THE LOW
LEVEL FLOW WILL HINDER ANY SIGNIFICANT FOG DEVELOPMENT...DESPITE MODELS
FAVORING SOME FOG POTENTIAL. IT WILL BE ANOTHER MUGGY NIGHT WITH
LOWS FROM THE MID 60S TO AROUND 70. MOS AND MAV GUIDANCE LOOKED A
LITTLE COOL WITH THE LOW LEVEL BOUNDARY MOISTURE IN PLACE. SO WENT
WITH MILDER GFS GUIDANCE.
FOR MONDAY AND MONDAY NIGHT...THE STRATUS WILL LIFT BY LATE MORNING.
THE AXIS OF THE SOUTHERN PLAINS TROUGH WILL PUSH DOWN INTO THE
SOUTHERN PLAINS AS LOW LEVEL INFLOW INCREASES ACROSS THE REGION. THE
SPC WRF TRIES TO SHOW SOME CONVECTION ACROSS THE DELTA WHILE ALL THE
OTHER MODELS AND WRF GUIDANCE WERE GENERALLY CLEAR. THINK THAT THE
CAP WILL HINDER ANY DEVELOPMENT DURING THE DAY. PUT THE BEST LOW DRY
POPS IN THE WEST. FOR MONDAY NIGHT 500 MB HEIGHTS WILL START TO
GRADUALLY LOWER FROM THE NORTHWEST. PUT IN SLIGHT TEEN POPS FOR
CONVECTION IN THE NORTHWEST AFTER MIDNIGHT. JUST IN CASE THERE WOULD
BE AN OUTFLOW BOUNDARY COMING FROM THE STORMS TO THE NORTHWEST.
EXPECT ANOTHER ROUND OF STRATUS...BUT ONCE AGAIN THE LOW LEVEL FLOW
WILL HINDER ANY SIGNIFICANT FOG DEVELOPMENT AFTER MIDNIGHT...DESPITE
MODEL PROGS. HIGHS ON MONDAY WILL BE FROM THE UPPER 80S TO AROUND
90. LOWS WILL BE FROM THE MID 60S TO THE LOWER 70S. WENT WITH GMOS
GUIDANCE ON HIGHS AND ONCE AGAIN MILDER GFS GUIDANCE ON LOWS.
FOR TUESDAY AND TUESDAY NIGHT...500 MB HEIGHTS WILL DROP FROM THE
NORTHWEST DURING THE PERIOD AS THE UPPER TROUGH AXIS PUSHES TOWARD
THE LOWER MISSISSIPPI VALLEY REGION. OUR CHANCES OF CONVECTION WILL
GRADUALLY INCREASE ACROSS THE REGION DURING THE PERIOD. THERE WILL
BE ENOUGH INSTABILITY AND LIMITED JET DYNAMICS FOR A FEW STRONG TO
SEVERE STORMS FOR TUESDAY AFTERNOON AND NIGHT. PWATS WILL INCREASE
TO AROUND 1.7 INCHES. THE BULK SHEAR WILL NOT BE IMPRESSIVE WITH
THIS SYSTEM THROUGH MOST OF TUESDAY NIGHT. A MIDLEVEL JET OF AROUND
50 KNOTS WILL MOVE ACROSS THE DELTA REGION FOR TUESDAY NIGHT. CAPES
WILL BE FROM 1500 TO 3500 J/KG...SHOWALTERS -3 TO -7. AN MCS WILL
MOVE ACROSS THE REGION DURING THE PERIOD FROM THE NORTHWEST TUESDAY
AFTERNOON AND NIGHT. SO AS FAR AS TEMPS ARE CONCERN HIGHS WILL BE
FROM THE MID TO UPPER 80S. LOWS WILL BE FROM THE MID 60S TO AROUND
70S. WENT CLOSE TO GMOS GUIDANCE ON HIGHS AND MILDER GFS GUIDANCE ON
LOWS. FOR POPS WENT CLOSE TO MAV GUIDANCE./17/
./PREVIOUS DISCUSSION...
.LONG TERM...WEDNESDAY THROUGH SUNDAY...THE WEAKENING UPPER LEVEL
TROUGH WILL SWING ACROSS OUR CWA WEDNESDAY BUT MODELS HAVE BACKED
OFF ON ANY FROPA IN OUR CWA AS THE FRONT FIZZLES NORTH OF OUR AREA.
OVERALL...THERMODYNAMIC PARAMETERS LOOK LESS FAVORABLE FOR SEVERE
WEATHER WEDNESDAY INTO THURSDAY BUT WL STILL HAVE A WARM MOIST
AIRMASS IN PLACE WITH RATHER STEEP MID LEVEL LAPSE RATES SO A FEW
STRONG STORMS WILL BE HARD TO RULE OUT. THE UPPER TROUGH AXIS WILL
BE EAST OF OUR CWA THURSDAY BUT NORTHWEST FLOW ALOFT WILL CONTINUE
OVER OUR CWA THROUGH SATURDAY. ALTHOUGH MOST OF THE CONVECTION WILL
SHOULD SHOW A DISTINCT DIURNAL TREND...MODELS INDICATE DISTURBANCES
ALOFT IN THE NW FLOW MAY SET OFF SOME CONVECTION OVER NIGHT THURSDAY
AND FRIDAY NIGHTS. IN ADDITION...BOTH GFS AND ECMWF SHOW A SURFACE
HIGH DROPPING OVER THE GREAT LAKES REGION FRIDAY NIGHT THAT MAY PUSH
A WEAK BACKDOOR COLD FRONT INTO OUR CWA SATURDAY. RIDGING SURFACE
AND ALOFT IS EXPECTED TO BUILD OVER OUR REGION SUNDAY RESULTING IN
DRY WEATHER. /22/17/
&&
.AVIATION...FEW TO SCATTERED CU ANTICIPATED THROUGH THE REMAINDER OF
THE AFTERNOON WITH BASES FROM 3 TO 5 KFT. WINDS WILL BE FROM THE
SOUTH AND GUSTY AT TIMES...PARTICULARLY IN THE DELTA. CONDITIONS
LATE THIS AFTERNOON THROUGH TOMORROW MORNING SHOULD BE QUITE SIMILAR
TO 24 HOURS AGO DUE TO PERSISTENT PATTERN. THUS...ANTICIPATE MIX OF
THE IFR/MVFR CEILINGS (BASES 800 TO 1500 FEET) DEVELOPING BETWEEN 3
AND 7 AM TOMORROW WITH NO DENSE FOG. CEILINGS WILL IMPROVE FROM 8 AM
THROUGH 10 AM...BUT MAY TAKE UNTIL NOON TO GO VFR IN ALL LOCATIONS.
/BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 68 90 67 89 / 10 10 7 10
MERIDIAN 67 92 66 90 / 10 8 6 8
VICKSBURG 70 89 71 89 / 10 11 8 15
HATTIESBURG 69 91 67 90 / 13 8 7 8
NATCHEZ 70 89 71 88 / 12 11 10 18
GREENVILLE 69 89 71 88 / 7 11 17 29
GREENWOOD 69 91 68 88 / 7 10 13 19
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
17/BB/22
000
FXUS64 KJAN 191457 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
957 AM CDT SUN MAY 19 2013
.UPDATE...LATEST SATELLITE IMAGERY SHOWED THE REGION UNDER THE
INFLUENCE OF A SHORTWAVE RIDGE WITH WEAK MOISTURE CONVERGENCE...WHICH WAS
BEING FLANKED BY A STRONG UPPER TROUGH OVER THE PLAINS AND SHORT
WAVE TROUGHING OVER THE SOUTHEAST US. STRATUS WAS NOTED OVER THE
REGION THIS MORNING...WHICH WILL LIFT FOR THIS AFTERNOON FOR PARTLY
CLOUDY SKIES WITH HIGH DEBRIS CLOUDS COMING FROM THE PLAINS SYSTEM.
AREA SOUNDINGS SHOWED GOOD LAPSE RATES ACROSS THE REGION OF AROUND
8C...WITH CAPES AROUND 2000...WITH GOOD DRYING FROM 900 TO AROUND
500 MB ABOVE THE LOW LEVEL MOIST BOUNDARY LAYER. DCAPES ACROSS THE
SOUTH WERE AROUND 1200 WITH COLD POOL HEIGHT AT 598 MB AT 61F. PWATS
WERE GENERALLY AROUND 1.2 INCHES . LATEST NAM SHOWS CAPE EXCEEDING 3000
J/KG WITH SHOWALTER INDEX AROUND -6 CENTERING ACROSS THE SOUTHWEST.
A FEW WRF MODELS WERE SHOWING SOME ISOLATED SHOWERS AND
THUNDERSTORMS ACROSS THE SOUTH HALF FOR THIS AFTERNOON WITH THE SPC
WRF SHOWING AN ISOLATED STRONG STORM IN THE SOUTHWEST. LATEST RUC/NAM SHOWS
SOME LOW LEVEL MOISTURE CONVERGENCE AT THE 1000-850 MB LEVEL FOR
THIS AFTERNOON...MAINLY ALONG AND WEST OF THE MS RIVER. THERE IS THE
POTENTIAL OF ONE OR MAYBE TWO STORMS ACROSS THE SOUTH HALF WITH SOME
POTENTIAL TO BE ON THE STRONG SIDE. WILL HOLD OFF ON MENTIONING THAT
IN THE HWO SINCE THE POTENTIAL FOR DEVELOPMENT IS ON THE SLIM SIDE.
SO HAVE PUT IN TEEN POPS ACROSS THE SOUTH HALF FOR THIS AFTERNOON.
WILL MONITOR FOR ANY DEVELOPMENT AND RECONSIDER THE HWO FOR LATER.
OTHERWISE HAVE ADJUSTED THE SKY GRIDS WITH THE LATEST 12Z NAM
GUIDANCE FOR A LITTLE MORE CLOUD COVER FOR PARTLY CLOUDY SKIES.
CURRENT HIGHS IN THE MID TO UPPER 80S LOOKS TO BE ON TRACK./17/
./PREVIOUS DISCUSSION...343 AM CDT SUN MAY 19 2013
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT...
SATELLITE AND OBSERVATIONS INDICATE STRATUS BUILDING INTO THE AREA
FROM THE SE THIS MORNING...WHILE SOME HIGH CLOUDS ALSO STREAM IN FROM
UPSTREAM CONVECTION OVER THE PLAINS. LATE SPRING HUMIDITY IS
PREVALENT WITH DEWPOINTS IN THE UPPER 60S TO NEAR 70.
EXPECT AREAS OF STRATUS TO CONTINUE TO OVERSPREAD REGION EARLY THIS
MORNING...AND THEN GRADUALLY GIVE WAY TO A MIX OF SUN...CUMULUS AND
HIGH CLOUDS THROUGH THE DAY. NORTHERN PERIPHERY OF AN UPPER
DISTURBANCE CURRENTLY ALONG UPPER TEXAS COAST PER WATER VAPOR IS
EXPECTED TO SKIRT ACROSS SOUTHERN PARTS OF FORECAST AREA THIS
AFTERNOON. CAPPING IS FORECAST BY THE MODELS TO HOLD TODAY...BUT
SOME CONCERN THAT COMBINATION OF DAYTIME HEATING AND SOME VERTICAL
MOTION ASSOCIATED WITH THE WAVE COULD ERODE CAPPING ENOUGH FOR AN
ISOLATED STORM OR TWO TO DEVELOP IN SOUTHERN AREAS. SUPPORT FOR THIS IN
THE MODELS IS PRETTY SLIM THOUGH...WITH ONLY SPC 4 KM WRF SHOWING ANY
DEVELOPMENT WITH OTHER NATIONAL/LOCAL HIGH RES AND GLOBAL MODELS ALL
DRY. FOR NOW WILL LEAVE ANY MENTION OF POPS OUT OF FORECAST...BUT
WILL NOTE THAT IF BY CHANCE ANYTHING WERE TO DEVELOP IT COULD BE
STRONG GIVEN MODEL FORECASTS OF STEEP LAPSE RATES AND MLCAPE VALUES
NEAR 3000 J/KG. GUIDANCE TEMPERATURES LOOK REASONABLE TODAY.
TONIGHT AND MON NIGHT SHOULD PRETTY MUCH BE A REPEAT OF THIS MORNING
WITH STRATUS INCREASING FROM THE SOUTH AND HIGH LEVEL CONVECTIVE
DEBRIS LIKELY INCREASING FROM THE W/NW. COMBINATION OF CLOUDS AND
DEWPOINTS IN 65 TO 70 DEGREE RANGE WOULD SEEM TO SUPPORT MINS A FEW
DEGREES ABOVE GFS MOS.
MONDAY SHOULD BE SIMILAR TO TODAY. MODELS SHOW AXIS OF HIGHEST PW AND
LOWEST CINH ACROSS WESTERN AREAS MON AFTERNOON. FOR NOW EXPECT THAT
BUILDING HEIGHTS AND CAPPING WILL WIN OUT EVEN HERE...AND WILL LEAVE
POPS OUT OF FORECAST. GUIDANCE TEMPERATURES ACCEPTED. /08/
.LONG TERM...TUESDAY THROUGH SUNDAY...BY TUESDAY MORNING THE NEARLY
STACKED LOW WILL BE OVER THE CENTRAL PLAINS WITH A SHORTWAVE
ROUNDING ITS BASE OVER THE SOUTHERN PLAINS. SHORTWAVE RIDGING ALOFT
AND SURFACE RIDGING FROM THE EAST WILL STILL BE DOMINANT ACROSS OUR
CWA TUESDAY MORNING BUT HEIGHTS WILL BE FALLING AS THE UPPER TROUGH
DRAWS CLOSER. A RATHER WARM AND HUMID DAY IS EXPECTED AS
TEMPERATURES TOP OUT IN THE UPPER 80S. ALONG AND WEST OF THE
MISSISSIPPI RIVER PWS ARE EXPECTED TO EXCEED AN INCH AND A HALF WITH
LOWER 70 DEGREE SURFACE DEW POINTS. DAYTIME HEATING SHOULD LEAD TO
AFTERNOON AND EVENING CONVECTION IN OUR WESTERN ZONES WHILE
CONVECTION REMAINS MORE INHIBITED EAST. WITH MLCAPES ABOVE
2000J/KG...7.5C/KM MID LEVEL LAPSE RATES AND VERTICAL TOTALS
29-30...A FEW STRONG TO SEVERE HAIL PRODUCING STORMS WILL BE
POSSIBLE. TUESDAY NIGHT INTO WEDNESDAY THE LOW WILL LIFT NE AND
WEAKEN OVER THE UPPER MISSISSIPPI RIVER VALLEY. THE WEAKENING UPPER
LEVEL TROUGH WILL SWING ACROSS OUR CWA WEDNESDAY BUT MODELS HAVE
BACKED OFF ON ANY FROPA IN OUR CWA AS THE FRONT FIZZLES NORTH OF OUR
AREA. OVERALL...THERMODYNAMIC PARAMETERS LOOK LESS FAVORABLE FOR
SEVERE WEATHER WEDNESDAY INTO THURSDAY BUT WL STILL HAVE A WARM MOIST
AIRMASS IN PLACE WITH RATHER STEEP MID LEVEL LAPSE RATES SO A FEW
STRONG STORMS WILL BE HARD TO RULE OUT. THE UPPER TROUGH AXIS WILL BE
EAST OF OUR CWA THURSDAY BUT NORTHWEST FLOW ALOFT WILL CONTINUE OVER
OUR CWA THROUGH SATURDAY. ALTHOUGH MOST OF THE CONVECTION WILL SHOULD
SHOW A DISTINCT DIURNAL TREND...MODELS INDICATE DISTURBANCES ALOFT IN
THE NW FLOW MAY SET OFF SOME CONVECTION OVER NIGHT THURSDAY AND
FRIDAY NIGHTS. IN ADDITION...BOTH GFS AND ECMWF SHOW A SURFACE HIGH
DROPPING OVER THE GREAT LAKES REGION FRIDAY NIGHT THAT MAY PUSH A
WEAK BACKDOOR COLD FRONT INTO OUR CWA SATURDAY. RIDGING SURFACE AND
ALOFT IS EXPECTED TO BUILD OVER OUR REGION SUNDAY RESULTING IN DRY
WEATHER. /22/
&&
.AVIATION...REMAINING STRATUS/BR SHOULD GRADUALLY MIX OUT/BURN OFF
THROUGH THE REMAINDER OF THE MORNING...WITH A MIX OF CUMULUS AT
030-040 AND SOME CIRRUS EXPECTED IN THE AFTERNOON. WINDS WILL BE
FROM THE SOUTH AND GUSTY AT TIMES...PARTICULARLY IN THE DELTA AS
25-35 KT 925 MB FLOW MIXES OUT. THERE COULD BE AN ISOLATED STORM OR
TWO DEVELOPING IN THE AFTERNOON ALONG AND SOUTH OF I-20...BUT THE
CHANCES OF ANY IMPACT TO AVIATION OPERATIONS IN THE AERODROME IS
VERY MINIMAL. GENERALLY EXPECT A REPEAT AS FAR AS STRATUS
DEVELOPMENT FOR TONIGHT AS WE ARE SEEING THIS MORNING. /BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 89 70 89 70 / 16 4 8 9
MERIDIAN 88 68 90 66 / 16 4 7 8
VICKSBURG 89 70 90 70 / 16 5 9 10
HATTIESBURG 88 70 89 68 / 20 4 9 6
NATCHEZ 89 71 88 70 / 18 4 10 7
GREENVILLE 90 71 89 70 / 10 6 9 11
GREENWOOD 89 70 89 69 / 10 6 9 10
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
17/BB/08/22
000
FXUS64 KJAN 190843
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
343 AM CDT SUN MAY 19 2013
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT...
SATELLITE AND OBSERVATIONS INDICATE STRATUS BUILDING INTO THE AREA
FROM THE SE THIS MORNING...WHILE SOME HIGH CLOUDS ALSO STREAM IN FROM
UPSTREAM CONVECTION OVER THE PLAINS. LATE SPRING HUMIDITY IS
PREVALENT WITH DEWPOINTS IN THE UPPER 60S TO NEAR 70.
EXPECT AREAS OF STRATUS TO CONTINUE TO OVERSPREAD REGION EARLY THIS
MORNING...AND THEN GRADUALLY GIVE WAY TO A MIX OF SUN...CUMULUS AND
HIGH CLOUDS THROUGH THE DAY. NORTHERN PERIPHERY OF AN UPPER
DISTURBANCE CURRENTLY ALONG UPPER TEXAS COAST PER WATER VAPOR IS
EXPECTED TO SKIRT ACROSS SOUTHERN PARTS OF FORECAST AREA THIS
AFTERNOON. CAPPING IS FORECAST BY THE MODELS TO HOLD TODAY...BUT
SOME CONCERN THAT COMBINATION OF DAYTIME HEATING AND SOME VERTICAL
MOTION ASSOCIATED WITH THE WAVE COULD ERODE CAPPING ENOUGH FOR AN
ISOLATED STORM OR TWO TO DEVELOP IN SOUTHERN AREAS. SUPPORT FOR THIS IN
THE MODELS IS PRETTY SLIM THOUGH...WITH ONLY SPC 4 KM WRF SHOWING ANY
DEVELOPMENT WITH OTHER NATIONAL/LOCAL HIGH RES AND GLOBAL MODELS ALL
DRY. FOR NOW WILL LEAVE ANY MENTION OF POPS OUT OF FORECAST...BUT
WILL NOTE THAT IF BY CHANCE ANYTHING WERE TO DEVELOP IT COULD BE
STRONG GIVEN MODEL FORECASTS OF STEEP LAPSE RATES AND MLCAPE VALUES
NEAR 3000 J/KG. GUIDANCE TEMPERATURES LOOK REASONABLE TODAY.
TONIGHT AND MON NIGHT SHOULD PRETTY MUCH BE A REPEAT OF THIS MORNING
WITH STRATUS INCREASING FROM THE SOUTH AND HIGH LEVEL CONVECTIVE
DEBRIS LIKELY INCREASING FROM THE W/NW. COMBINATION OF CLOUDS AND
DEWPOINTS IN 65 TO 70 DEGREE RANGE WOUULD SEEM TO SUPPORT MINS A FEW
DEGREES ABOVE GFS MOS.
MONDAY SHOULD BE SIMILAR TO TODAY. MODELS SHOW AXIS OF HIGHEST PW AND
LOWEST CINH ACROSS WESTERN AREAS MON AFTERNOON. FOR NOW EXPECT THAT
BUILDING HEIGHTS AND CAPPING WILL WIN OUT EVEN HERE...AND WILL LEAVE
POPS OUT OF FORECAST. GUIDANCE TEMPERATURES ACCEPTED. /08/
.LONG TERM...TUESDAY THROUGH SUNDAY...BY TUESDAY MORNING THE NEARLY
STACKED LOW WILL BE OVER THE CENTRAL PLAINS WITH A SHORTWAVE
ROUNDING ITS BASE OVER THE SOUTHERN PLAINS. SHORTWAVE RIDGING ALOFT
AND SURFACE RIDGING FROM THE EAST WILL STILL BE DOMINANT ACROSS OUR
CWA TUESDAY MORNING BUT HEIGHTS WILL BE FALLING AS THE UPPER TROUGH
DRAWS CLOSER. A RATHER WARM AND HUMID DAY IS EXPECTED AS
TEMPERATURES TOP OUT IN THE UPPER 80S. ALONG AND WEST OF THE
MISSISSIPPI RIVER PWS ARE EXPECTED TO EXCEED AN INCH AND A HALF WITH
LOWER 70 DEGREE SURFACE DEW POINTS. DAYTIME HEATING SHOULD LEAD TO
AFTERNOON AND EVENING CONVECTION IN OUR WESTERN ZONES WHILE
CONVECTION REMAINS MORE INHIBITED EAST. WITH MLCAPES ABOVE
2000J/KG...7.5C/KM MID LEVEL LAPSE RATES AND VERTICAL TOTALS
29-30...A FEW STRONG TO SEVERE HAIL PRODUCING STORMS WILL BE
POSSIBLE. TUESDAY NIGHT INTO WEDNESDAY THE LOW WILL LIFT NE AND
WEAKEN OVER THE UPPER MISSISSIPPI RIVER VALLEY. THE WEAKENING UPPER
LEVEL TROUGH WILL SWING ACROSS OUR CWA WEDNESDAY BUT MODELS HAVE
BACKED OFF ON ANY FROPA IN OUR CWA AS THE FRONT FIZZLES NORTH OF OUR
AREA. OVERALL...THERMODYNAMIC PARAMETERS LOOK LESS FAVORABLE FOR
SEVERE WEATHER WEDNESDAY INTO THURSDAY BUT WL STILL HAVE A WARM MOIST
AIRMASS IN PLACE WITH RATHER STEEP MID LEVEL LAPSE RATES SO A FEW
STRONG STORMS WILL BE HARD TO RULE OUT. THE UPPER TROUGH AXIS WILL BE
EAST OF OUR CWA THURSDAY BUT NORTHWEST FLOW ALOFT WILL CONTINUE OVER
OUR CWA THROUGH SATURDAY. ALTHOUGH MOST OF THE CONVECTION WILL SHOULD
SHOW A DISTINCT DIURNAL TREND...MODELS INDICATE DISTURBANCES ALOFT IN
THE NW FLOW MAY SET OFF SOME CONVECTION OVER NIGHT THURSDAY AND
FRIDAY NIGHTS. IN ADDITION...BOTH GFS AND ECMWF SHOW A SURFACE HIGH
DROPPING OVER THE GREAT LAKES REGION FRIDAY NIGHT THAT MAY PUSH A
WEAK BACKDOOR COLD FRONT INTO OUR CWA SATURDAY. RIDGING SURFACE AND
ALOFT IS EXPECTED TO BUILD OVER OUR REGION SUNDAY RESULTING IN DRY
WEATHER. /22/
&&
.AVIATION...
LOW LEVEL FLOW APPEARS TO BE STRONG ENOUGH THIS MORNING TO FAVOR
STRATUS OVER FOG...WITH EXPECTATION THAT IFR CIGS WILL BE PREVALENT
MOST AREAS BY 12Z. THINKING IS THAT LOWEST VSBY WILL OCCUR AT KGTR
WHERE HEAVY RAIN FELL FRI/FRI NIGHT AND WINDS SHOULD BE
LIGHTEST...MAY SEE SOME IFR VSBY HERE. ELSEWHERE EXPECT NO WORSE
THAN MVFR VSBYS IN BR THROUGH 14Z. STRATUS/BR SHOULD GRADUALLY MIX
OUT/BURN OFF THROUGH THE MORNING...WITH A MIX OF CUMULUS AT 030-040
AND SOME CIRRUS EXECTED BY AFTERNOON. WINDS WILL BE FROM THE SOUTH
AND GUSTY AT TIMES...PARTICULARLY IN THE DELTA AS 25-35 KT 925 MB
FLOW MIXES OUT. GENERALLY EXPECT A REPEAT AS FAR AS STRATUS
DEVELOPMENT FOR TONIGHT AS WE ARE SEEING THIS MORNING. /08/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 89 70 89 70 / 4 5 8 9
MERIDIAN 88 68 90 66 / 6 5 7 8
VICKSBURG 89 70 90 70 / 5 5 9 10
HATTIESBURG 88 70 89 68 / 5 5 9 6
NATCHEZ 89 71 88 70 / 5 5 10 7
GREENVILLE 90 71 89 70 / 6 5 9 11
GREENWOOD 89 70 89 69 / 6 5 9 10
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
08/22
000
FXUS64 KJAN 190227 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
927 PM CDT SAT MAY 18 2013
.UPDATE...
LOOKS LIKE THE CAP MANAGED TO HOLD OFF ANY STORMS THAT HAD THE
POTENTIAL OF FORMING THIS AFTERNOON. A QUIET AND HUMID NIGHT WILL
THEREFORE PREVAIL. FOG CHANCES IN THE MORNING HOURS ARE PRETTY GOOD,
ESPECIALLY SOUTH AND EAST OF THE NATCHEZ TRACE, AS THE SOUTHERLY LOW
LEVEL FLOW WILL BE PRETTY LIGHT DURING THOSE COOL HOURS OF THE
MORNING. TOOK OUT THE SLIGHT CHANCE POPS IN THE NORTHEAST FOR
TONIGHT AND ADJUSTED THE HOURLY TEMPS FOR THE UPDATE. /10/
&&
.AVIATION...
THE PRIMARY AVIATION CONCERN FOR LATER TONIGHT INTO SATURDAY MORNING
WILL BE ANOTHER EPISODE OF MVFR/IFR CATEGORY STRATUS IMPACTING MOST
TAF SITES IN SOUTHERLY LOW-LEVEL FLOW...AND POTENTIALLY FOG AS WELL
AS BOUNDARY LAYER WINDS ARE EXPECTED TO BE LIGHTER. EXPECT ANY FOG TO
DISSIPATE BY MID MORNING WITH CEILINGS BREAKING UP OR LIFTING INTO
VFR CATEGORY SHORTLY THEREAFTER IN THE STRONG MAY SUNSHINE. /EC/
&&
.PREV DISCUSSION... /ISSUED 414 PM CDT SAT MAY 18 2013/
SHORT TERM...
SATURDAY EVENING THROUGH TUESDAY MORNING...
TEMPERATURES HAVE WARMED NICELY THIS AFTERNOON AS RIDGING BEGINS TO
BUILD INTO THE REGION. CLOUDS ARE FINALLY CLEARING IN THE NORTHEAST
BUT A THERMAL GRADIENT IS EVIDENT. THERE IS STILL A CHANCE THERE
COULD BE SOME DEVELOPMENT OF STORMS LATE TODAY INTO TONIGHT IN THE
NORTHEAST. IF ANY CAN DEVELOP...GOOD INSTABILITY AND LAPSE RATES WILL
FAVOR STRONG STORMS CAPABLE OF SMALL HAIL AND GUSTY WINDS. UPPER AND
SURFACE RIDGING WILL BEGIN TO BUILD INTO THE REGION TONIGHT. MAV
GUIDANCE OVERNIGHT TONIGHT LOOKED GOOD. JUST BUMPED UP LOWS SLIGHTLY
IN THE WEST DUE TO SOME CLOUDS MOVING IN OVERNIGHT. TEMPERATURES WILL
FALL INTO THE MID TO UPPER 60S AND WITH HIGH LOW LEVEL
MOISTURE...STRONGLY CAPPED AND DRY MID LEVELS AND LIGHT LOW LEVEL
FLOW...THERE IS A GOOD POSSIBILITY OF SOME LOW STRATUS AND
PATCHY/AREAS OF FOG OVERNIGHT TONIGHT BETWEEN 10-15Z FOR MOST OF THE
REGION. SREF PROBS AND LVORI VALUES ARE HIGHEST IN SOUTHEAST
MISSISSIPPI. THUS INTRODUCED PATCHY FOG FOR AREAS SOUTHEAST OF THE
NORTHWEST DELTA...WITH AREAS OF FOG IN FAR SOUTHEAST MISSISSIPPI.
UPPER RIDGING WILL CONTINUALLY MOVE INTO THE REGION AS A STRONG AND
DEEP LONGWAVE TROUGH MOVES THROUGH THE CENTRAL/UPPER PLAINS. THE
REGION WILL STAY CAPPED AND LOW STRATUS/FOG WILL HANG INTO THE EARLY
MORNING HOURS BEFORE MIXING OUT. TEMPERATURES WILL BE ABOVE NORMAL
AS H5 HEIGHTS INCREASE AND TEMPERATURES ALOFT INCREASE SLIGHTLY.
TEMPERATURES ON SUNDAY WILL WARM INTO THE UPPER 80S TO NEAR 90
DEGREES. MAV TEMPERATURES LOOK GOOD FOR TEMPERATURES ON SUNDAY.
SHORTWAVE RIDGE AXIS WILL GRADUALLY BUILD TO THE EAST OVERNIGHT ON
SUNDAY...LEADING TO WEAK ISENTROPIC LIFT AND MID TO HIGH LEVEL
CLOUDS IN THE REGION. MAV TEMPERATURE LOOK GOOD SUNDAY NIGHT. THERE
WILL AGAIN BE THE POTENTIAL FOR SOME PATCHY TO AREAS OF FOG IN THE
SOUTH AND SOUTHEAST DUE TO STRONGLY CAPPED ENVIRONMENT AND LIGHT LOW
LEVEL FLOW BUT DECIDED TO HOLD OFF FOR NOW TO INTRODUCE FOG SUNDAY
NIGHT AS THERE COULD BE MORE LOW STRATUS THAN FOG AS LOW LEVEL FLOW
IS SLIGHTLY STRONGER. TEMPERATURES WILL AGAIN BE VERY WARM AND HUMID
MONDAY AFTERNOON AS UPPER RIDGE WILL BE SITUATED TO THE SOUTHEAST
AND INCREASING SOUTHERLY FLOW INCREASES PWATS NEAR 1.3-1.5 INCHES.
STRONG CAPPING AND INCREASING LOW LEVEL FLOW WILL LEAD TO LOW
STRATUS AGAIN ON MONDAY NIGHT INTO TUESDAY MORNING. WENT CLOSE TO
MAV ON TEMPERATURES TUESDAY NIGHT. STRONG UPPER TROUGH AND SURFACE
LOW PRESSURE WILL GRADUALLY PROPAGATE TO THE EAST/NORTHEAST OVER THE
CENTRAL TO HIGH PLAINS AND DRAG A COLD FRONT TOWARDS THE REGION. THE
COLD FRONT SHOULD BE SITUATED NORTHWEST OF THE REGION ON MONDAY
MORNING TO TUESDAY. DECIDED TO HOLD OFF ON POPS UNTIL AFTER 12Z
TUESDAY. HOWEVER...EURO HAS SPED UP SLIGHTLY IN THE FORWARD
PROGRESSION OF THE COLD FRONT BRINGING THE COLD FRONT NEAR THE
NORTHWEST DELTA LATE TUESDAY AFTERNOON. THIS WILL NEED TO BE
MONITORED FOR LATER UPDATES. REST OF THE FORECAST IS ON TRACK AND
RELEVANT PORTION OF LONG TERM DISCUSSION IS ATTACHED. /DC/
LONG TERM...
TUESDAY AFTERNOON INTO NEXT WEEKEND...
BY TUESDAY PWS IN THE WEST ARE EXPECTED TO EXCEED AN INCH
AND A HALF WITH A WEAKER CAP IN PLACE. DAYTIME HEATING SHOULD LEAD
TO SCATTERED MAINLY AFTERNOON AND EVENING CONVECTION. THERMODYNAMIC
PARAMETERS INDICATE POTENTIAL FOR A FEW STRONG STORMS OVER THE DELTA
REGION. THE GFS AND ECMWF AGREE THAT THE COLD FRONT WILL MOVE INTO
OUR WESTERN ZONES WEDNESDAY AND THAT THE CLOSED LOW WILL OPEN UP
INTO A WEAKENING TROUGH AS IT MOVES ACROSS OUR REGION BUT THEY
DIFFER SIGNIFICANTLY ON TIMING AND PROGRESSION OF THE COLD FRONT.
THE GFS BRINGS THE COLD FRONT THROUGH OUR CWA BY THURSDAY MORNING
WHILE THE ECMWF STALLS THE FRONT AND DISSIPATES IT BY THURSDAY
MORNING. EITHER WAY STRONG TO SEVERE STORMS LOOK POSSIBLE OVER THE
WESTERN PORTIONS OF THE AREA AGAIN WEDNESDAY. HAVE LEANED TOWARD
THE GFS THIS FCST AND WL RESULT IN COOLER AND DRIER WEATHER FOR
THURSDAY AND FRIDAY. BOTH GFS AND ECMWF SHOW A SECOND CLOSED LOW
DEVELOPING OVER THE OHIO VALLEY FRIDAY RESULTING IN AN OMEGA BLOCK
WITH THE RIDGE OVER THE CENTRAL CONUS GOING INTO NEXT WEEKEND. THIS
WOULD RESULT IN CONTINUED NORTHWEST FLOW ALOFT OVER OUR REGION AND
COOLER THAN NORMAL TEMPERATURES INTO NEXT WEEKEND. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 67 89 70 89 / 2 4 4 8
MERIDIAN 67 88 68 91 / 3 6 4 7
VICKSBURG 67 89 70 89 / 2 4 5 9
HATTIESBURG 68 89 70 90 / 3 3 4 9
NATCHEZ 68 88 71 87 / 2 5 4 10
GREENVILLE 69 89 71 89 / 2 6 6 9
GREENWOOD 69 90 70 89 / 2 6 6 9
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
000
FXUS64 KJAN 182114
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
414 PM CDT SAT MAY 18 2013
.SHORT TERM...
SATURDAY EVENING THROUGH TUESDAY MORNING...
TEMPERATURES HAVE WARMED NICELY THIS AFTERNOON AS RIDGING BEGINS TO
BUILD INTO THE REGION. CLOUDS ARE FINALLY CLEARING IN THE NORTHEAST
BUT A THERMAL GRADIENT IS EVIDENT. THERE IS STILL A CHANCE THERE
COULD BE SOME DEVELOPMENT OF STORMS LATE TODAY INTO TONIGHT IN THE
NORTHEAST. IF ANY CAN DEVELOP...GOOD INSTABILITY AND LAPSE RATES WILL
FAVOR STRONG STORMS CAPABLE OF SMALL HAIL AND GUSTY WINDS. UPPER AND
SURFACE RIDGING WILL BEGIN TO BUILD INTO THE REGION TONIGHT. MAV
GUIDANCE OVERNIGHT TONIGHT LOOKED GOOD. JUST BUMPED UP LOWS SLIGHTLY
IN THE WEST DUE TO SOME CLOUDS MOVING IN OVERNIGHT. TEMPERATURES WILL
FALL INTO THE MID TO UPPER 60S AND WITH HIGH LOW LEVEL
MOISTURE...STRONGLY CAPPED AND DRY MID LEVELS AND LIGHT LOW LEVEL
FLOW...THERE IS A GOOD POSSIBILITY OF SOME LOW STRATUS AND
PATCHY/AREAS OF FOG OVERNIGHT TONIGHT BETWEEN 10-15Z FOR MOST OF THE
REGION. SREF PROBS AND LVORI VALUES ARE HIGHEST IN SOUTHEAST
MISSISSIPPI. THUS INTRODUCED PATCHY FOG FOR AREAS SOUTHEAST OF THE
NORTHWEST DELTA...WITH AREAS OF FOG IN FAR SOUTHEAST MISSISSIPPI.
UPPER RIDGING WILL CONTINUALLY MOVE INTO THE REGION AS A STRONG AND
DEEP LONGWAVE TROUGH MOVES THROUGH THE CENTRAL/UPPER PLAINS. THE
REGION WILL STAY CAPPED AND LOW STRATUS/FOG WILL HANG INTO THE EARLY
MORNING HOURS BEFORE MIXING OUT. TEMPERATURES WILL BE ABOVE NORMAL
AS H5 HEIGHTS INCREASE AND TEMPERATURES ALOFT INCREASE SLIGHTLY.
TEMPERATURES ON SUNDAY WILL WARM INTO THE UPPER 80S TO NEAR 90
DEGREES. MAV TEMPERATURES LOOK GOOD FOR TEMPERATURES ON SUNDAY.
SHORTWAVE RIDGE AXIS WILL GRADUALLY BUILD TO THE EAST OVERNIGHT ON
SUNDAY...LEADING TO WEAK ISENTROPIC LIFT AND MID TO HIGH LEVEL
CLOUDS IN THE REGION. MAV TEMPERATURE LOOK GOOD SUNDAY NIGHT. THERE
WILL AGAIN BE THE POTENTIAL FOR SOME PATCHY TO AREAS OF FOG IN THE
SOUTH AND SOUTHEAST DUE TO STRONGLY CAPPED ENVIRONMENT AND LIGHT LOW
LEVEL FLOW BUT DECIDED TO HOLD OFF FOR NOW TO INTRODUCE FOG SUNDAY
NIGHT AS THERE COULD BE MORE LOW STRATUS THAN FOG AS LOW LEVEL FLOW
IS SLIGHTLY STRONGER. TEMPERATURES WILL AGAIN BE VERY WARM AND HUMID
MONDAY AFTERNOON AS UPPER RIDGE WILL BE SITUATED TO THE SOUTHEAST
AND INCREASING SOUTHERLY FLOW INCREASES PWATS NEAR 1.3-1.5 INCHES.
STRONG CAPPING AND INCREASING LOW LEVEL FLOW WILL LEAD TO LOW
STRATUS AGAIN ON MONDAY NIGHT INTO TUESDAY MORNING. WENT CLOSE TO
MAV ON TEMPERATURES TUESDAY NIGHT. STRONG UPPER TROUGH AND SURFACE
LOW PRESSURE WILL GRADUALLY PROPAGATE TO THE EAST/NORTHEAST OVER THE
CENTRAL TO HIGH PLAINS AND DRAG A COLD FRONT TOWARDS THE REGION. THE
COLD FRONT SHOULD BE SITUATED NORTHWEST OF THE REGION ON MONDAY
MORNING TO TUESDAY. DECIDED TO HOLD OFF ON POPS UNTIL AFTER 12Z
TUESDAY. HOWEVER...EURO HAS SPED UP SLIGHTLY IN THE FORWARD
PROGRESSION OF THE COLD FRONT BRINGING THE COLD FRONT NEAR THE
NORTHWEST DELTA LATE TUESDAY AFTERNOON. THIS WILL NEED TO BE
MONITORED FOR LATER UPDATES. REST OF THE FORECAST IS ON TRACK AND
RELEVANT PORTION OF LONG TERM DISCUSSION IS ATTACHED. /DC/
.LONG TERM...
TUESDAY AFTERNOON INTO NEXT WEEKEND...
BY TUESDAY PWS IN THE WEST ARE EXPECTED TO EXCEED AN INCH
AND A HALF WITH A WEAKER CAP IN PLACE. DAYTIME HEATING SHOULD LEAD
TO SCATTERED MAINLY AFTERNOON AND EVENING CONVECTION. THERMODYNAMIC
PARAMETERS INDICATE POTENTIAL FOR A FEW STRONG STORMS OVER THE DELTA
REGION. THE GFS AND ECMWF AGREE THAT THE COLD FRONT WILL MOVE INTO
OUR WESTERN ZONES WEDNESDAY AND THAT THE CLOSED LOW WILL OPEN UP
INTO A WEAKENING TROUGH AS IT MOVES ACROSS OUR REGION BUT THEY
DIFFER SIGNIFICANTLY ON TIMING AND PROGRESSION OF THE COLD FRONT.
THE GFS BRINGS THE COLD FRONT THROUGH OUR CWA BY THURSDAY MORNING
WHILE THE ECMWF STALLS THE FRONT AND DISSIPATES IT BY THURSDAY
MORNING. EITHER WAY STRONG TO SEVERE STORMS LOOK POSSIBLE OVER THE
WESTERN PORTIONS OF THE AREA AGAIN WEDNESDAY. HAVE LEANED TOWARD
THE GFS THIS FCST AND WL RESULT IN COOLER AND DRIER WEATHER FOR
THURSDAY AND FRIDAY. BOTH GFS AND ECMWF SHOW A SECOND CLOSED LOW
DEVELOPING OVER THE OHIO VALLEY FRIDAY RESULTING IN AN OMEGA BLOCK
WITH THE RIDGE OVER THE CENTRAL CONUS GOING INTO NEXT WEEKEND. THIS
WOULD RESULT IN CONTINUED NORTHWEST FLOW ALOFT OVER OUR REGION AND
COOLER THAN NORMAL TEMPERATURES INTO NEXT WEEKEND. /22/
&&
.AVIATION...ANY CEILINGS ARE ALMOST ENTIRELY VFR NOW ACROSS THE
AERODROME ALTHOUGH THERE MAY STILL BE A PATCH OR TWO OF MVFR FOR THE
NEXT HOUR OR SO AROUND THE GOLDEN TRIANGLE. OTHERWISE...FEW TO
SCATTERED CU THIS AFTERNOON HAS BASES FROM 3 TO 5 KFT. THE ONLY
POTENTIAL TROUBLESPOT STILL LOOKS TO BE AROUND THE GOLDEN TRIANGLE
(CBM/GTR) LATE THIS AFTERNOON INTO THIS EVENING WHERE AT LEAST
ISOLATED AFT/EVE STORMS WILL REMAIN A POSSIBILITY DUE TO THE VICINITY
OF A STATIONARY FRONT. IF ANY STORMS MANAGE TO AFFECT THOSE SITES
THEY COULD OF COURSE BRING TEMPORARY MVFR TO IFR CONDITIONS...AS WELL
AS THE POTENTIAL FOR GUSTY WINDS AND LOCALIZED TURBULENCE. TONIGHT
ANTICIPATE WIDESPREAD REDEVELOPMENT OF LOW CLOUDS IN THE IN THE IFR
RANGE...ALTHOUGH TRUE FOG WILL BE A NON- NEGLIGIBLE POSSIBILITY IN
PORTIONS OF SE MS. RAIN CHANCES TOMORROW WILL BE VERY LOW FOR THE
REGION ALTHOUGH CEILING RESTRICTIONS MAY TAKE UNTIL MIDDAY TO IMPROVE
TO VFR IN ALL AREAS. /BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 67 89 70 89 / 2 4 4 8
MERIDIAN 67 88 68 91 / 14 6 4 7
VICKSBURG 67 89 70 89 / 2 4 5 9
HATTIESBURG 68 89 70 90 / 6 3 4 9
NATCHEZ 68 88 71 87 / 2 5 4 10
GREENVILLE 69 89 71 89 / 2 6 6 9
GREENWOOD 69 90 70 89 / 6 6 6 9
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/22/BB
000
FXUS64 KJAN 181540 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
1040 AM CDT SAT MAY 18 2013
.UPDATE...
WARM AND HUMID CONDITIONS WILL INCREASE THIS AFTERNOON AS H5 RIDGE
AXIS TO THE WEST BUILDS INTO THE REGION. TEMPERATURES WILL WARM INTO
THE MID/UPPER 80S. REGIONAL 12Z SOUNDINGS INDICATE THE STRONG CAPPING
IN THE REGION. THIS CAPPING WILL WEAKEN LATER THIS AFTERNOON AND AID
IN THE SLIGHT CLEARING OF CLOUDS THROUGH THE REGION. THERE IS
CURRENTLY A BOUNDARY IN NORTHEAST MISSISSIPPI FROM THE PREVIOUS
CONVECTION LAST NIGHT. THIS BOUNDARY AND UPPER S/WV...AS INDICATED
PER WATER VAPOR IMAGERY...MAY SERVE AS A FOCUS FOR ACTIVITY LATER
THIS AFTERNOON TO EVENING. IT IS DEFINITELY POSSIBLE THAT THE
ACTIVITY COULD STAY JUST TO THE NORTH OF THE REGION. HOWEVER...SEEMED
PRUDENT TO INTRODUCE SOME SLIGHT CHANCE POPS UNTIL 6Z DUE TO THE
CLOSE VICINITY OF THIS BOUNDARY. SOME HI-RES/GLOBAL MODELS ARE
INDICATING SOME SHOWERS AND THUNDERSTORMS DEVELOPING IN THE NORTHEAST
FROM THE GOLDEN TRIANGLE AND CONTINUING TO MOVE SOUTHEAST. THE
ENVIRONMENT WILL BE FAVORABLE FOR THUNDERSTORM DEVELOPMENT WITH
700-500MB LAPSE RATES AROUND 7-8.5 DEG C/KM...MLCAPES AROUND
2000-3000 J/KG AND SHOWALTERS AROUND -5 TO -7. ANY STORMS THAT
DEVELOP COULD BE STRONG AND PRODUCE SMALL HAIL AND WIND GUSTS UP TO
40 TO 50MPH. ONLY OTHER CHANGES WERE TO SLIGHTLY BUMP UP HIGHS/HOURLY
TEMP GRIDS DUE TO THE AREA WARMING QUICKER. SLIGHTLY ADJUSTED SKY
COVER GRIDS. REST OF THE FORECAST IS ON TRACK. /DC/
&&
.AVIATION...LOW LEVEL MOISTURE INFLUX IS STILL BRINGING MVFR
CEILINGS TO PORTIONS OF THE REGION AT MID MORNING...BUT THESE
RESTRICTIONS SHOULD IMPROVE IN ALL AREAS BEFORE NOON.
OTHERWISE...EXPECT FEW TO SCATTERED CU AROUND THIS AFTERNOON WITH
BASES FROM 3 TO 5 KFT. THE ONLY POTENTIAL TROUBLESPOT COULD BE
AROUND THE GOLDEN TRIANGLE (CBM/GTR) WHERE AT LEAST ISOLATED AFT/EVE
STORMS WILL REMAIN A POSSIBILITY DUE TO THE VICINITY OF A STATIONARY
FRONT. IF ANY STORMS MANAGE TO AFFECT THOSE SITES THEY COULD OF
COURSE BRING TEMPORARY MVFR TO IFR CONDITIONS...AS WELL AS THE
POTENTIAL FOR GUSTY WINDS AND LOCALIZED TURBULENCE. TONIGHT
ANTICIPATE WIDESPREAD REDEVELOPMENT OF LOW CLOUDS IN THE IFR TO MVFR
RANGE...ALTHOUGH TRUE FOG WILL BE QUITE LIMITED. /BB/
&&
.PREV DISCUSSION... /ISSUED 420 AM CDT SAT MAY 18 2013/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT...ASIDE FROM THE EARLY
MORNING/ONGOING CONVECTION...THE SHORT TERM PORTION OF THE FORECAST
WILL BE QUIET AND BEST CHARACTERIZED AS EARLY SUMMER LIKE THANKS TO
THE WARM/HUMID CONDITIONS THAT ARE EXPECTED.
EARLY THIS MORNING WE HAVE LINGERING CONVECTION (SOME HAVE BEEN
STRONG TO SVR) ACROSS THE NE/GOLDEN TRIANGLE REGION OF THE CWA. THIS
ACTIVITY HAS BEEN FOCUSING ON AN OLD BOUNDARY FROM FRIDAY MORNINGS
ACTIVITY AND THEN INVIGORATED BY SOLID MOISTURE ADV ATOP THE
BOUNDARY AND SOME ASSISTED LIFT FROM A S/WV MOVING THROUGH N MS.
THIS ACTIVITY WILL LINGER A BIT THIS MORNING BUT ONLY EXPECT IT TO
LAST THROUGH 6-8 AM AND BE FOCUSED ACROSS THE FAR NE CWA.
FOR THE REST OF THE CWA AND EVEN OUR FAR NE AFTER THIS MORNING
ACTIVITY EXITS...LOOK FOR PRECIP FREE CONDITIONS AS ATMOSPHERIC
CAPPING BUILDS OVER THE AREA. IN TANDEM WITH THIS...DRY ADV WILL
OVERTAKE THE AREA IN THE LOW LEVELS AND KEEP ANY PRECIP AT BAY. I
WILL ONLY MENTION POPS/WX THIS MORNING TO ACCOUNT FOR THE EARLY AM
ACTIVITY THEN KEEP THE GRIDS WX FREE FOR THE AFTERNOON.
DESPITE THE DRY AIR ADV JUST OFF THE SFC AND IN THE CAPPING
LAYER...BOUNDARY LAYER MOISTURE WILL REMAIN HIGH WITH DEWPTS
CONTINUING TO RUN IN THE UPPER 60S TO AROUND 70 DEGREES. THIS WILL
KEEP THAT HUMID FEELING IN THE AIR. THE CAPPING LAYER WILL ALSO
SERVE TO SUPPORT LOW STRATUS IN THE MORNING...BUT GIVE WAY TO FEW OR
NO CLOUDS DURING THE DAY. THIS WILL HELP WITH STRONG SFC HEATING
BOTH TODAY AND SUNDAY (ESP SUNDAY).
LONG TERM...MONDAY THROUGH SATURDAY...MEDIUM RANGE MODELS ARE IN
FAIR AGREEMENT AT THE START OF THE LONG TERM WITH A CLOSED LOW OVER
THE NORTHERN PLAINS AND A POTENT SHORTWAVE DROPPING OVER THE FOUR
CORNERS REGION. THESE FEATURES WILL SUPPORT A COLD FRONT THAT WILL
DROP INTO OUR CWA WEDNESDAY AND GIVE US OUR NEXT BEST CHANCE FOR
RAIN. AHEAD OF THIS SYSTEM...SHORTWAVE RIDGING ALOFT AND A SURFACE
RIDGE OVER THE GULF COAST WILL BE DOMINANT MONDAY OVER OUR CWA.
MODEL SOUNDINGS INDICATE SOME EARLY MORNING STRATUS AND A DECENT
CAP. THE CAP MAY HOLD BUT THE STRATUS SHOULD BURN OFF RAPIDLY AND A
WARM AND HUMID DAY IS EXPECTED. WARMER THAN NORMAL AFTERNOON HIGHS
IN THE UPPER 80S AT MOST SITES WILL COMBINE WITH UPPER 60 DEGREE DEW
POINTS. BY TUESDAY PWS IN THE WEST ARE EXPECTED TO EXCEED AN INCH
AND A HALF WITH A WEAKER CAP IN PLACE. DAYTIME HEATING SHOULD LEAD
TO SCATTERED MAINLY AFTERNOON AND EVENING CONVECTION. THERMODYNAMIC
PARAMETERS INDICATE POTENTIAL FOR A FEW STRONG STORMS OVER THE DELTA
REGION. THE GFS AND ECMWF AGREE THAT THE COLD FRONT WILL MOVE INTO
OUR WESTERN ZONES WEDNESDAY AND THAT THE CLOSED LOW WILL OPEN UP
INTO A WEAKENING TROUGH AS IT MOVES ACROSS OUR REGION BUT THEY
DIFFER SIGNIFICANTLY ON TIMING AND PROGRESSION OF THE COLD FRONT.
THE GFS BRINGS THE COLD FRONT THROUGH OUR CWA BY THURSDAY MORNING
WHILE THE ECMWF STALLS THE FRONT AND DISSIPATES IT BY THURSDAY
MORNING. EITHER WAY STRONG TO SEVERE STORMS LOOK POSSIBLE OVER THE
WESTERN PORTIONS OF THE AREA AGAIN WEDNESDAY. HAVE LEANED TOWARD
THE GFS THIS FCST AND WL RESULT IN COOLER AND DRIER WEATHER FOR
THURSDAY AND FRIDAY. BOTH GFS AND ECMWF SHOW A SECOND CLOSED LOW
DEVELOPING OVER THE OHIO VALLEY FRIDAY RESULTING IN AN OMEGA BLOCK
WITH THE RIDGE OVER THE CENTRAL CONUS GOING INTO NEXT WEEKEND. THIS
WOULD RESULT IN CONTINUED NORTHWEST FLOW ALOFT OVER OUR REGION AND
COOLER THAN NORMAL TEMPERATURES INTO NEXT WEEKEND. /22/
&&
.AVIATION...
MAIN ISSUE THIS MORNING WILL BE MVFR CEILINGS WITH A FEW
SITES SEEING A PERIOD OF IFR CEILINGS. THESE CEILINGS ARE NOT
EXPECTED TO LINGER TOO LONG AND IMPROVE TO VFR BETWEEN 15-17Z. VFR
CONDITIONS WILL LINGER FOR THE MAJORITY OF THE DAY.
HOWEVER...ANOTHER ROUND OF STRATUS IS EXPECTED TONIGHT. LOOK FOR IFR
CEILINGS TO AGAIN BE POSSIBLE AND LIKELY BEGIN AFTER 07-09Z. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 89 68 88 70 / 0 2 0 0
MERIDIAN 87 68 87 67 / 16 14 0 0
VICKSBURG 88 69 88 69 / 0 2 0 0
HATTIESBURG 89 69 87 69 / 8 6 0 0
NATCHEZ 87 69 87 70 / 0 2 0 0
GREENVILLE 87 70 89 70 / 1 2 0 0
GREENWOOD 87 68 89 70 / 9 6 0 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/BB/22/CME
000
FXUS64 KJAN 180935
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
420 AM CDT SAT MAY 18 2013
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT...ASIDE FROM THE EARLY
MORNING/ONGOING CONVECTION...THE SHORT TERM PORTION OF THE FORECAST
WILL BE QUIET AND BEST CHARACTERIZED AS EARLY SUMMER LIKE THANKS TO
THE WARM/HUMID CONDITIONS THAT ARE EXPECTED.
EARLY THIS MORNING WE HAVE LINGERING CONVECTION (SOME HAVE BEEN
STRONG TO SVR) ACROSS THE NE/GOLDEN TRIANGLE REGION OF THE CWA. THIS
ACTIVITY HAS BEEN FOCUSING ON AN OLD BOUNDARY FROM FRIDAY MORNINGS
ACTIVITY AND THEN INVIGORATED BY SOLID MOISTURE ADV ATOP THE
BOUNDARY AND SOME ASSISTED LIFT FROM A S/WV MOVING THROUGH N MS.
THIS ACTIVITY WILL LINGER A BIT THIS MORNING BUT ONLY EXPECT IT TO
LAST THROUGH 6-8 AM AND BE FOCUSED ACROSS THE FAR NE CWA.
FOR THE REST OF THE CWA AND EVEN OUR FAR NE AFTER THIS MORNING
ACTIVITY EXITS...LOOK FOR PRECIP FREE CONDITIONS AS ATMOSPHERIC
CAPPING BUILDS OVER THE AREA. IN TANDEM WITH THIS...DRY ADV WILL
OVERTAKE THE AREA IN THE LOW LEVELS AND KEEP ANY PRECIP AT BAY. I
WILL ONLY MENTION POPS/WX THIS MORNING TO ACCOUNT FOR THE EARLY AM
ACTIVITY THEN KEEP THE GRIDS WX FREE FOR THE AFTERNOON.
DESPITE THE DRY AIR ADV JUST OFF THE SFC AND IN THE CAPPING
LAYER...BOUNDARY LAYER MOISTURE WILL REMAIN HIGH WITH DEWPTS
CONTINUING TO RUN IN THE UPPER 60S TO AROUND 70 DEGREES. THIS WILL
KEEP THAT HUMID FEELING IN THE AIR. THE CAPPING LAYER WILL ALSO
SERVE TO SUPPORT LOW STRATUS IN THE MORNING...BUT GIVE WAY TO FEW OR
NO CLOUDS DURING THE DAY. THIS WILL HELP WITH STRONG SFC HEATING
BOTH TODAY AND SUNDAY (ESP SUNDAY).
.LONG TERM...MONDAY THROUGH SATURDAY...MEDIUM RANGE MODELS ARE IN
FAIR AGREEMENT AT THE START OF THE LONG TERM WITH A CLOSED LOW OVER
THE NORTHERN PLAINS AND A POTENT SHORTWAVE DROPPING OVER THE FOUR
CORNERS REGION. THESE FEATURES WILL SUPPORT A COLD FRONT THAT WILL
DROP INTO OUR CWA WEDNESDAY AND GIVE US OUR NEXT BEST CHANCE FOR
RAIN. AHEAD OF THIS SYSTEM...SHORTWAVE RIDGING ALOFT AND A SURFACE
RIDGE OVER THE GULF COAST WILL BE DOMINANT MONDAY OVER OUR CWA.
MODEL SOUNDINGS INDICATE SOME EARLY MORNING STRATUS AND A DECENT
CAP. THE CAP MAY HOLD BUT THE STRATUS SHOULD BURN OFF RAPIDLY AND A
WARM AND HUMID DAY IS EXPECTED. WARMER THAN NORMAL AFTERNOON HIGHS
IN THE UPPER 80S AT MOST SITES WILL COMBINE WITH UPPER 60 DEGREE DEW
POINTS. BY TUESDAY PWS IN THE WEST ARE EXPECTED TO EXCEED AN INCH
AND A HALF WITH A WEAKER CAP IN PLACE. DAYTIME HEATING SHOULD LEAD
TO SCATTERED MAINLY AFTERNOON AND EVENING CONVECTION. THERMODYNAMIC
PARAMETERS INDICATE POTENTIAL FOR A FEW STRONG STORMS OVER THE DELTA
REGION. THE GFS AND ECMWF AGREE THAT THE COLD FRONT WILL MOVE INTO
OUR WESTERN ZONES WEDNESDAY AND THAT THE CLOSED LOW WILL OPEN UP
INTO A WEAKENING TROUGH AS IT MOVES ACROSS OUR REGION BUT THEY
DIFFER SIGNIFICANTLY ON TIMING AND PROGRESSION OF THE COLD FRONT.
THE GFS BRINGS THE COLD FRONT THROUGH OUR CWA BY THURSDAY MORNING
WHILE THE ECMWF STALLS THE FRONT AND DISSIPATES IT BY THURSDAY
MORNING. EITHER WAY STRONG TO SEVERE STORMS LOOK POSSIBLE OVER THE
WESTERN PORTIONS OF THE AREA AGAIN WEDNESDAY. HAVE LEANED TOWARD
THE GFS THIS FCST AND WL RESULT IN COOLER AND DRIER WEATHER FOR
THURSDAY AND FRIDAY. BOTH GFS AND ECMWF SHOW A SECOND CLOSED LOW
DEVELOPING OVER THE OHIO VALLEY FRIDAY RESULTING IN AN OMEGA BLOCK
WITH THE RIDGE OVER THE CENTRAL CONUS GOING INTO NEXT WEEKEND. THIS
WOULD RESULT IN CONTINUED NORTHWEST FLOW ALOFT OVER OUR REGION AND
COOLER THAN NORMAL TEMPERATURES INTO NEXT WEEKEND. /22/
&&
.AVIATION...MAIN ISSUE THIS MORNING WILL BE MVFR CEILINGS WITH A FEW
SITES SEEING A PERIOD OF IFR CEILINGS. THESE CEILINGS ARE NOT
EXPECTED TO LINGER TOO LONG AND IMPROVE TO VFR BETWEEN 15-17Z. VFR
CONDITIONS WILL LINGER FOR THE MAJORITY OF THE DAY.
HOWEVER...ANOTHER ROUND OF STRATUS IS EXPECTED TONIGHT. LOOK FOR IFR
CEILINGS TO AGAIN BE POSSIBLE AND LIKELY BEGIN AFTER 07-09Z. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 87 68 88 69 / 12 6 13 8
MERIDIAN 87 66 89 68 / 25 15 12 8
VICKSBURG 87 66 88 69 / 12 4 13 9
HATTIESBURG 88 69 87 67 / 9 12 7 6
NATCHEZ 86 67 88 67 / 8 7 10 7
GREENVILLE 88 69 89 69 / 13 4 13 10
GREENWOOD 87 69 89 69 / 28 8 13 9
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
CME/22/CME
000
FXUS64 KJAN 180412 AAB
AFDJAN
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
1112 PM CDT FRI MAY 17 2013
.UPDATE...QUICK UPDATE TO COVER THE POTENTIAL FOR A FEW STRONG
STORMS AND LOCALLY HEAVY RAIN FOR THE REMAINDER OF THE NIGHT ACROSS
THE NE PORTION OF THE CWA. THIS EVENING...A WELL DEFINED BOUNDARY
WAS NOTED BOTH AT THE SFC AND UP THROUGH ABOUT 850MB. THIS BOUNDARY
EXTENDS GENERALLY FROM GWO TO JUST NORTH OF MEI. THIS WILL PROVIDE A
FOCUS FOR SCT/NUMEROUS SHRA/TSRA OVERNIGHT AS SOLID MOISTURE/THETA E
ADV CONTINUES ATOP THAT FEATURE IN THE 0-2KM LAYER.
ADDITIONALLY...THE AIRMASS ALOFT IS MODERATELY UNSTABLE WITH
1500-2000 J/KG OF MUCAPE AND MULI`S OF -5 TO -7C. THERE IS ALSO
SUFFICIENT DEEP LAYER SHEAR OF 30KTS TO SUPPORT ORGANIZED UPDRAFTS.
AT THIS TIME AND DESPITE ONGOING CONVECTION...WE ARE LACKING A
SUFFICIENT TRIGGER AND THIS ACTIVITY IS BEING DRIVEN BY THE SOLID
MOISTURE ADV NEAR THE BOUNDARY. HOWEVER...IN A BOUT 2-4 HRS...A
SUBTLE BUT EVIDENT S/WV (CURRENTLY NEAR MEM) WILL SLIP TO THE SE AND
PROVIDE A BETTER TRIGGER AND INCREASED ASCENT. NEAR TERM GUIDANCE
INDICATES CONVECTION INCREASING AFTER 06-08Z ACROSS THE NE CWA
THROUGH ABOUT 12-13Z. WITH FAVORABLE ENVIRONMENT FOR STRONG
CONVECTION...WILL MENTION THE RISK FOR A FEW STRONG STORMS
OVERNIGHT. HOWEVER...THE MAIN RISK WILL LIKELY COME FROM HEAVY RAIN
AS STORMS WILL HAVE THE POTENTIAL TO TRAIN/MOVE OVER THE SAME AREAS.
PARTS OF THE HWY 82 CORRIDOR HAVE SEEN 1-2 INCHES ON FRIDAY AND
ADDITIONAL PRECIP COULD POSE A FLOODING RISK...ESPECIALLY IF 2-4
INCHES OCCUR. WE WILL BE UPDATING THE GRAPHICS AND HWO TO ACCOUNT
FOR THIS POTENTIAL. /CME/
&&
.PREV DISCUSSION... /ISSUED 945 PM CDT FRI MAY 17 2013/
UPDATE...
SCATTERED SHOWERS ARE STILL DEVELOPING IN CENTRAL/NE MS. THE UPPER LOW
CONTINUES EASTWARD TONIGHT AND THE PRIMARY HEAVY RAIN THREAT HAS
MOVED INTO CENTRAL AL. HOWEVER, UPSTREAM FORMATION OF SCATTERED
STORMS STILL REMAINS POSSIBLE HERE IN CENTRAL/NE MS. ADJUSTED POPS
FOR THE UPDATE. MOSTLY LOWERED THEM EVERYWHERE, KEEPING A 30 PERCENT
CHANCE FOR NE MS. SHOULD BE A HUMID AND MUGGY NIGHT ACROSS THE
REMAINDER OF ARKLAMISS. LOWS WILL BE IN THE UPPER 60S. /10/
&&
.AVIATION...
THE PRIMARY AVIATION CONCERN FOR LATER TONIGHT INTO SATURDAY MORNING
WILL BE ANOTHER EPISODE OF MVFR/IFR CATEGORY STRATUS IMPACTING MOST
TAF SITES IN SOUTHERLY FLOW. EXPECT THE CEILINGS TO LIFT INTO VFR
CATEGORY BY EARLY AFTERNOON...WITH ANY SHOWER/TSRA CHANCES CONFINED
TO THE GWO/GTR/MEI AREA. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 69 87 68 88 / 11 12 6 13
MERIDIAN 67 87 66 89 / 20 25 15 12
VICKSBURG 68 87 66 88 / 7 12 4 13
HATTIESBURG 68 88 69 87 / 4 9 12 7
NATCHEZ 69 86 67 88 / 5 8 7 10
GREENVILLE 70 88 69 89 / 13 13 4 13
GREENWOOD 69 87 69 89 / 30 28 8 13
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
CME
000
FXUS64 KJAN 180245 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
945 PM CDT FRI MAY 17 2013
.UPDATE...
SCATTERED SHOWERS ARE STILL DEVELOPING IN CENTRAL/NE MS. THE UPPER LOW
CONTINUES EASTWARD TONIGHT AND THE PRIMARY HEAVY RAIN THREAT HAS
MOVED INTO CENTRAL AL. HOWEVER, UPSTREAM FORMATION OF SCATTERED
STORMS STILL REMAINS POSSIBLE HERE IN CENTRAL/NE MS. ADJUSTED POPS
FOR THE UPDATE. MOSTLY LOWERED THEM EVERYWHERE, KEEPING A 30 PERCENT
CHANCE FOR NE MS. SHOULD BE A HUMID AND MUGGY NIGHT ACROSS THE
REMAINDER OF ARKLAMISS. LOWS WILL BE IN THE UPPER 60S. /10/
&&
.AVIATION...
THE PRIMARY AVIATION CONCERN FOR LATER TONIGHT INTO SATURDAY MORNING
WILL BE ANOTHER EPISODE OF MVFR/IFR CATEGORY STRATUS IMPACTING MOST
TAF SITES IN SOUTHERLY FLOW. EXPECT THE CEILINGS TO LIFT INTO VFR
CATEGORY BY EARLY AFTERNOON...WITH ANY SHOWER/TSRA CHANCES CONFINED
TO THE GWO/GTR/MEI AREA. /EC/
&&
.PREV DISCUSSION... /ISSUED 316 PM CDT FRI MAY 17 2013/
SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT...AN UPPER LOW IS LOCATED
OVER SOUTHEAST MISSOURI THIS MORNING AND CONTINUES TO MOVE NORTHEAST
AND WILL BE CENTERED OVER SOUTHERN ILLINOIS BY TONIGHT. STORMS
CONTINUE TO DEVELOP ALONG A BOUNDARY THAT STRETCHES FROM EAST TO
WEST ALONG THE HIGHWAY 82 CORRIDOR. FLASH FLOODING HAS BEEN OCCURRING
OVER GRENADA THIS AFTERNOON AS STORMS TRAIN OVER THE COUNTY...BUT THE
HEAVIEST ACTIVITY HAS SHIFTED TO THE EAST. FURTHER SOUTH A CAPPED
ENVIRONMENT IS IN PLACE WITH THE JAN MORNING SOUNDING INDICATING A
PRETTY STRONG CAP AROUND H700. BUFR SOUNDINGS CONTINUE TO INDICATE A
STRENGTHENING CAP AND RISING HEIGHTS THIS AFTERNOON AND EVENING OVER
THE CENTRAL AND SOUTHWESTERN PORTIONS OF THE AREA. CONTINUES TO LOOK
LIKE THE BEST CHANCE FOR THE CONVECTION THIS AFTERNOON AND EVENING
WILL BE OVER THE NORTH-CENTRAL...NORTHEAST AND EASTERN PORTIONS OF THE
AREA. SOME OF THESE STORMS COULD BE STRONG TO POSSIBLY SEVERE DURING
THE LATE AFTERNOON AND EARLY EVENING HOURS.
EXPECT THE FOCUS OF THE STORMS TO REMAIN OVER THE NORTHEASTERN
PORTIONS OF THE AREA OVERNIGHT AS ANOTHER SHORT WAVE MOVES ACROSS
THE AREA. THE ECMWF INDICATES THE POTENTIAL FOR SOME STORMS OVER THE
DELTA AREAS THIS EVENING...BUT IT IS AN OUTLIER. WILL HAVE TO
CONTINUE TO MONITOR FOR FLASH FLOODING OVER THESE AREAS OVERNIGHT AS
THE STORMS DO HAVE POTENTIAL FOR TRAINING OVER THE SAME AREAS THAT
RECEIVED RAINFALL TODAY.
UPPER RIDGING BUILDS IN OVER THE AREA ON SATURDAY...BUT THERE IS
STILL SOME POTENTIAL FOR SOME AT LEAST ISOLATED STORMS OVER THE
NORTHEAST SATURDAY AFTERNOON. THE REMAINDER OF THE AREA SHOULD BE
DRY WITH VERY WARM TEMPS UP NEAR 90. EXPECT MAINLY DRY CONDITIONS ON
SUNDAY AND SUNDAY NIGHT AS UPPER AND SURFACE RIDGING PREVAIL OVER
THE AREA. DID NOT MAKE ANY CHANGES TO THE FORECAST BEYOND SUNDAY
NIGHT...SO WILL ATTACH THE APPLICABLE PORTIONS OF THE EXTENDED BELOW.
/15/
PREVIOUS LONG TERM...THE RIDGE BEGINS TO EDGE TO THE EAST MONDAY
BUT WILL EXERT ENOUGH INFLUENCE TO MAINTAIN A RELATIVELY DRY AIR MASS
OVER THE REGION. LOW LEVEL MOISTURE WILL BE ON THE INCREASE IN
PERSISTENT LOW LEVEL SLY FLOW. THIS WILL BE REFLECTED IN HUMID
AFTERNOONS AND NIGHTTIME LOWS THAT COULD POTENTIALLY HANG AROUND
RECORD HIGH VALUES FOR MORNING LOW TEMPS.
PRECIPITABLE WATER VALUES WILL BE ON THE INCREASE OVER WRN ZONES BY
TUESDAY EVENING AHEAD OF A BOUNDARY APPROACHING THE ARKLATEX
REGION...INCREASING TO 1.5-1.8 INCHES OVER MUCH OF WRN AND NRN
PORTIONS OF THE FORECAST AREA WEDNESDAY AND THE REMAINDER OF THE
AREA THURSDAY. THE SURFACE BOUNDARY IS FORECAST TO WEAKEN AND MODELS
DIFFER ON WHETHER A LOW LEVEL CONVERGENCE ZONE ASSOCIATED WITH THE
REMNANTS OF THE BOUNDARY WILL PIVOT INTO THE AREA LATE IN THE
EXTENDED PERIOD. CHANCES FOR SCATTERED SHOWERS AND TSTMS WILL
INCREASE FOR WEDNESDAY AND THURSDAY AS MOISTURE DEEPENS AND THE CAP
WEAKENS. /03/
&&
.AVIATION...
VFR CONDS TO PERSIST THRU THE AFTN OUTSIDE OF SHRA/TSRA
THAT MAY IMPACT AREAS EAST OF I-55 AND N OF I-20 THRU THE AFTN.
SHRA/TSRA ACTIVITY MAY PERSIST INTO THE OVRNGT HRS ACROSS THE GOLDEN
TRIANGLE BEFORE MOVING EAST BY TOMORROW MORNING. A FEW STRONGER
STORMS W/WIND GUSTS TO 50-60MPH/HAIL/PSBLY A TORNADO MAY DEVELOP
ACROSS THIS AREA THRU 23Z. SFC WINDS WL REMAIN SLY OVER THE NEXT 24
HRS WITH A FEW GUSTS TO 15-18KTS OR SO PSBL THIS AFTN. /BK/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 69 87 68 88 / 28 12 6 13
MERIDIAN 67 87 66 89 / 39 25 15 12
VICKSBURG 68 87 66 88 / 20 12 4 13
HATTIESBURG 68 88 69 87 / 15 9 12 7
NATCHEZ 69 86 67 88 / 9 8 7 10
GREENVILLE 70 88 69 89 / 32 13 4 13
GREENWOOD 69 87 69 89 / 39 28 8 13
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
/
000
FXUS64 KJAN 172016
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
316 PM CDT FRI MAY 17 2013
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT...AN UPPER LOW IS LOCATED
OVER SOUTHEAST MISSOURI THIS MORNING AND CONTINUES TO MOVE NORTHEAST
AND WILL BE CENTERED OVER SOUTHERN ILLINOIS BY TONIGHT. STORMS
CONTINUE TO DEVELOP ALONG A BOUNDARY THAT STRETCHES FROM EAST TO
WEST ALONG THE HIGHWAY 82 CORRIDOR. FLASH FLOODING HAS BEEN OCCURRING
OVER GRENADA THIS AFTERNOON AS STORMS TRAIN OVER THE COUNTY...BUT THE
HEAVIEST ACTIVITY HAS SHIFTED TO THE EAST. FURTHER SOUTH A CAPPED
ENVIRONMENT IS IN PLACE WITH THE JAN MORNING SOUNDING INDICATING A
PRETTY STRONG CAP AROUND H700. BUFR SOUNDINGS CONTINUE TO INDICATE A
STRENGTHENING CAP AND RISING HEIGHTS THIS AFTERNOON AND EVENING OVER
THE CENTRAL AND SOUTHWESTERN PORTIONS OF THE AREA. CONTINUES TO LOOK
LIKE THE BEST CHANCE FOR THE CONVECTION THIS AFTERNOON AND EVENING
WILL BE OVER THE NORTH-CENTRAL...NORTHEAST AND EASTERN PORTIONS OF THE
AREA. SOME OF THESE STORMS COULD BE STRONG TO POSSIBLY SEVERE DURING
THE LATE AFTERNOON AND EARLY EVENING HOURS.
EXPECT THE FOCUS OF THE STORMS TO REMAIN OVER THE NORTHEASTERN
PORTIONS OF THE AREA OVERNIGHT AS ANOTHER SHORT WAVE MOVES ACROSS
THE AREA. THE ECMWF INDICATES THE POTENTIAL FOR SOME STORMS OVER THE
DELTA AREAS THIS EVENING...BUT IT IS AN OUTLIER. WILL HAVE TO
CONTINUE TO MONITOR FOR FLASH FLOODING OVER THESE AREAS OVERNIGHT AS
THE STORMS DO HAVE POTENTIAL FOR TRAINING OVER THE SAME AREAS THAT
RECEIVED RAINFALL TODAY.
UPPER RIDGING BUILDS IN OVER THE AREA ON SATURDAY...BUT THERE IS
STILL SOME POTENTIAL FOR SOME AT LEAST ISOLATED STORMS OVER THE
NORTHEAST SATURDAY AFTERNOON. THE REMAINDER OF THE AREA SHOULD BE
DRY WITH VERY WARM TEMPS UP NEAR 90. EXPECT MAINLY DRY CONDITIONS ON
SUNDAY AND SUNDAY NIGHT AS UPPER AND SURFACE RIDGING PREVAIL OVER
THE AREA. DID NOT MAKE ANY CHANGES TO THE FORECAST BEYOND SUNDAY
NIGHT...SO WILL ATTACH THE APPLICABLE PORTIONS OF THE EXTENDED BELOW.
/15/
.PREVIOUS LONG TERM...THE RIDGE BEGINS TO EDGE TO THE EAST MONDAY
BUT WILL EXERT ENOUGH INFLUENCE TO MAINTAIN A RELATIVELY DRY AIR MASS
OVER THE REGION. LOW LEVEL MOISTURE WILL BE ON THE INCREASE IN
PERSISTENT LOW LEVEL SLY FLOW. THIS WILL BE REFLECTED IN HUMID
AFTERNOONS AND NIGHTTIME LOWS THAT COULD POTENTIALLY HANG AROUND
RECORD HIGH VALUES FOR MORNING LOW TEMPS.
PRECIPITABLE WATER VALUES WILL BE ON THE INCREASE OVER WRN ZONES BY
TUESDAY EVENING AHEAD OF A BOUNDARY APPROACHING THE ARKLATEX
REGION...INCREASING TO 1.5-1.8 INCHES OVER MUCH OF WRN AND NRN
PORTIONS OF THE FORECAST AREA WEDNESDAY AND THE REMAINDER OF THE
AREA THURSDAY. THE SURFACE BOUNDARY IS FORECAST TO WEAKEN AND MODELS
DIFFER ON WHETHER A LOW LEVEL CONVERGENCE ZONE ASSOCIATED WITH THE
REMNANTS OF THE BOUNDARY WILL PIVOT INTO THE AREA LATE IN THE
EXTENDED PERIOD. CHANCES FOR SCATTERED SHOWERS AND TSTMS WILL
INCREASE FOR WEDNESDAY AND THURSDAY AS MOISTURE DEEPENS AND THE CAP
WEAKENS. /03/
&&
.AVIATION...VFR CONDS TO PERSIST THRU THE AFTN OUTSIDE OF SHRA/TSRA
THAT MAY IMPACT AREAS EAST OF I-55 AND N OF I-20 THRU THE AFTN.
SHRA/TSRA ACTIVITY MAY PERSIST INTO THE OVRNGT HRS ACROSS THE GOLDEN
TRIANGLE BEFORE MOVING EAST BY TOMORROW MORNING. A FEW STRONGER
STORMS W/WIND GUSTS TO 50-60MPH/HAIL/PSBLY A TORNADO MAY DEVELOP
ACROSS THIS AREA THRU 23Z. SFC WINDS WL REMAIN SLY OVER THE NEXT 24
HRS WITH A FEW GUSTS TO 15-18KTS OR SO PSBL THIS AFTN. /BK/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 69 87 68 88 / 16 10 6 9
MERIDIAN 67 87 66 88 / 23 9 11 9
VICKSBURG 68 87 67 89 / 11 8 4 9
HATTIESBURG 68 88 67 88 / 8 6 8 11
NATCHEZ 68 87 68 87 / 5 4 6 11
GREENVILLE 70 87 69 88 / 13 14 4 10
GREENWOOD 69 88 69 88 / 30 17 7 10
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
15/BK
000
FXUS64 KJAN 171548
AFDJAN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
1045 AM CDT FRI MAY 17 2013
.UPDATE...AN UPPER LOW IS LOCATED OVER SOUTHEAST MISSOURI THIS
MORNING AND CONTINUES TO MOVE NORTHEAST. STORMS STRETCH FROM EAST TO
WEST ALONG THE HIGHWAY 82 CORRIDOR AND FURTHER SOUTH A CAPPED
ENVIRONMENT IS IN PLACE WITH THE JAN MORNING SOUNDING INDICATING A
PRETTY STRONG CAP AROUND H700. BUFR SOUNDINGS INDICATE THAT THIS CAP
WILL ONLY GET STRONGER THROUGH THE DAY. WITH HEIGHTS INCREASING
THROUGH THE DAY FROM THE SOUTHWEST AND THE CAP INCREASING IN
STRENGTH OVER THE BULK OF THE AREA..EXPECT THE BEST CHANCES FOR
CONVECTION TO BE OVER THE NORTHEASTERN PORTIONS OF THE AREA THIS
AFTERNOON. SOME OF THESE STORMS COULD BE STRONG TO POSSIBLE
SEVERE...AND WILL CONTINUE TO HIGHLIGHT THAT IN THE HWO AND
GRAPHICASTS. THE CURRENT FORECAST LOOKS ON TRACK AND NO UPDATES ARE
NEEDED AT THIS TIME./15/
.SHORT TERM...FOCUS TODAY WILL BE ON THE PRECIP DEVELOPMENT AND
POTENTIAL FOR SOME STRONG/POSSIBLY SVR STORMS. VARIOUS COMPLEXITIES
EXIST WITH THIS FORECAST AND CONFIDENCE IS NOT VERY HIGH...DESPITE
IT BEING IN THE NEAR TERM.
THE MAIN PLAYER & DRIVING FORCE FOR THE NEXT 12-24HRS IS THE
SPINNING MID/UPPER LOW SITUATED TO OUR NORTH. WHILE WE REMAIN ON THE
SOUTHERN PERIPHERY OF THE SYSTEM...WE ARE IN THE FAVORED REGION
WHERE SPOKES OF ENERGY(LIFT) CAN ROTATE AROUND THE SYSTEM AND
COMBINE WITH INCREASING LOW LEVEL MOISTURE/CONVERGENCE AND PROVIDE
PRECIP. LOOK FOR THE CORE OF THE SYSTEM TO SLOWLY SHIFT EAST TODAY
WITH A PORTION OF OUR FORECAST AREA REMAINING IN A ZONE THAT WILL
FEEL THE INFLUENCE FROM A FEW PIECES OF ENERGY. ONE BEING DURING THE
DAY PERIOD AND ANOTHER OVERNIGHT.
CHALLENGES TODAY LIE IN WHAT INFLUENCES WILL THE MORNING ACTIVITY
HAVE FOR CONVECTION DEVELOPMENT LATER IN THE DAY. THE RECENT TRENDS
SUPPORT THE NORTHERN CWA (HWY 82) WILL CONTINUE TO SEE ACTIVITY
THROUGH MORNING/MIDDAY RESULTING IN POOR LAPSE RATES FOR THAT AREA
AND LIMITED INSTABILITY. HOWEVER...SUCH ACTIVITY COULD PROVIDE A
NICE BOUNDARY FOR AFTERNOON STORMS SOUTH OF HWY 82 AND JUST NORTH OF
I-20. HERE...STEEPER LAPSE RATES WILL BE DEVELOPING THUS GREATER
INSTABILITY. HOWEVER...MODELS ALSO CONTINUE TO INDICATE THAT WITH
THESE STEEPER LAPSE RATES WILL COME STRONGER CAPPING AND RISING MID
LEVEL HEIGHTS. FORECAST MODELS REALIZE THIS AND CONTINUE TO LIMIT
PRECIP DEVELOPMENT TOO FAR S AND SW.
WITH ALL THE VARYING CHALLENGES IN FIGURING OUT THE EVOLUTION TO
STORMS TODAY...I WILL FOLLOW SOME SORT OF BLEND OF DIFFERENT
OUTCOMES. I WILL FOCUS THE BETTER PRECIP/STORM RISK ACROSS THE NE
QUAD. AS FOR STRONG/SVR POTENTIAL...CONFIDENCE IS NOT GREAT...BUT
POTENTIAL DOES EXIST AND WILL HIGHLIGHT AN AREA SIMILAR TO WHAT HAS
BEEN ADVERTISED WITH MORE OF A FOCUS ON THAT NE QUAD. AT THIS
TIME...NO PARTICULAR TYPE OF SVR WX LOOKS TO BE THE
FOCUS...HAIL...DMG WINDS AND EVEN A TORNADO OR TWO APPEAR POSSIBLE.
TIMING IS TOUGH...BUT IT SEEMS LIKE MIDDAY INTO THE AFTERNOON FIT
BEST.
FOR TONIGHT...MORE UNCERTAINTY EXISTS...BUT THE FORECAST MODELS
CONTINUE TO SHOW/HINT AT WHAT LEFT OVER BOUNDARIES FROM EARLIER
ACTIVITY WILL SERVE AS A FOCUS FOR SOME ADDITIONAL DEVELOPMENT. THE
FOCUS SEEMS TO BE MORE TOWARD THE GOLDEN TRIANGLE AREA WITH THE
STORM THREAT SHIFTING TO MORE OF A HEAVY RAIN SITUATION. DURING THIS
TIME...850MB FLOW WILL VEER TO MORE WESTERLY AND SUPPORT STORM
REDEVELOPMENT FROM THE BACK END WHICH WILL LIKELY CAUSE SOME SORT OF
STORM TRAINING. JUST WHERE ACTIVITY SETS UP IS HARD TO PINPOINT BUT
WHERE IT DOES...A LOCALIZED AREA COULD SEE SOME EXCESSIVE PRECIP.
FOR SAT-SAT NGT...MID/UPPER LEVEL RIDGING BUILDS IN ALONG WITH
STRONGER CAPPING. THIS WILL LIMIT PRECIP POTENTIAL BUT ALSO ALLOW
FOR WARMER TEMPS. /CME/
.LONG TERM...UPPER RIDGING WILL CONTINUE SUNDAY...KEEPING CONDITIONS
DRY AND MAINTAINING RELATIVELY WARM TEMPERATURES FOR THE AREA. THE
RIDGE BEGINS TO EDGE TO THE EAST MONDAY BUT WILL EXERT ENOUGH
INFLUENCE TO MAINTAIN A RELATIVELY DRY AIR MASS OVER THE REGION. LOW
LEVEL MOISTURE WILL BE ON THE INCREASE IN PERSISTENT LOW LEVEL SLY
FLOW. THIS WILL BE REFLECTED IN HUMID AFTERNOONS AND NIGHTTIME LOWS
THAT COULD POTENTIALLY HANG AROUND RECORD HIGH VALUES FOR MORNING
LOW TEMPS.
PRECIPITABLE WATER VALUES WILL BE ON THE INCREASE OVER WRN ZONES BY
TUESDAY EVENING AHEAD OF A BOUNDARY APPROACHING THE ARKLATEX
REGION...INCREASING TO 1.5-1.8 INCHES OVER MUCH OF WRN AND NRN
PORTIONS OF THE FORECAST AREA WEDNESDAY AND THE REMAINDER OF THE
AREA THURSDAY. THE SURFACE BOUNDARY IS FORECAST TO WEAKEN AND MODELS
DIFFER ON WHETHER A LOW LEVEL CONVERGENCE ZONE ASSOCIATED WITH THE
REMNANTS OF THE BOUNDARY WILL PIVOT INTO THE AREA LATE IN THE
EXTENDED PERIOD. CHANCES FOR SCATTERED SHOWERS AND TSTMS WILL
INCREASE FOR WEDNESDAY AND THURSDAY AS MOISTURE DEEPENS AND THE CAP
WEAKENS. /03/
&&
.AVIATION...CIG WL CONTINUE TRENDING VFR THRU 17Z W/VFR CONDS XPCTD
THEREAFTER OUTSIDE OF SHRA/TSRA THAT MAY IMPACT AREAS EAST OF I-55
AND N OF I-20 THRU THE AFTN. SHRA/TSRA ACTIVITY MAY PERSIST INTO THE
OVRNGT HRS ACROSS THE GOLDEN TRIANGLE BEFORE MOVING EAST BY TOMORROW
MORNING. A FEW STRONGER STORMS W/WIND GUSTS TO 50-60MPH/HAIL/PSBLY A
TORNADO MAY DEVELOP ACROSS THIS AREA 18-23Z. SFC WINDS WL REMAIN SLY
OVER THE NEXT 24 HRS WITH A FEW GUSTS TO 15KTS OR SO PSBL THIS AFTN.
/BK/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 85 69 87 68 / 32 16 10 6
MERIDIAN 84 67 87 66 / 37 23 9 11
VICKSBURG 85 68 87 67 / 25 11 8 4
HATTIESBURG 86 68 88 67 / 13 8 6 8
NATCHEZ 85 68 87 68 / 13 5 4 6
GREENVILLE 83 70 87 69 / 36 13 14 4
GREENWOOD 82 69 88 69 / 49 22 17 7
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
CME/03/
| 
