Area Forecast Discussion
Issued by NWS Jackson, MS

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000
FXUS64 KJAN 190200 AAA
AFDJAN

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
900 PM CDT THU SEP 18 2014

.UPDATE...
THIS EVENING`S ACTIVITY...INITIALLY SPURRED BY A COMBINATION OF THE
FRONTAL BOUNDARY AND SHORTWAVE MOVING INTO THE DELTA
EARLIER...EVOLVED INTO OUTFLOWS UPON OUTFLOWS INTERACTING WITH YET
MORE OUTFLOWS. THESE STORMS ARE NOW WINDING DOWN AND SHOULD CONTINUE
TO DO SO PER THE HI-RES MODELS AND THE CURRENT TREND. SOME LINGERING
OUTFLOW BOUNDARIES IN THE SOUTHERN PART OF THE CWA STILL HAVE THE
POTENTIAL TO MEET UP WITH THE SEA BREEZE-FORCED STORMS MOVING NORTH
INTO MS FROM LA AT THIS TIME. SEVERE STORMS FROM THIS INTERACTION ARE
NOT LIKELY BUT COULD KEEP CONVECTIVE ACTIVITY FROM WANING TOO SOON.
CLOUDS WILL SLOWLY THIN OUT AS THE NIGHT GOES WITH SOME PATCHY
FOG/LOW STRATUS POSSIBLE IN THE MORNING HOURS. FIXED SOME OF THE
HOURLY TEMPS ALONG WITH POPS BEFORE MIDNIGHT FOR THE UPDATE. /10/

&&

.AVIATION...
SHRA/TSRA ARE DIMINISHING OVER THE AREA WITH LOSS OF DAYTIME
HEATING. STRONG UPPER LEVEL WINDS WILL KEEP HIGH LEVEL CLOUDS
STREAMING ACROSS THE AREA AND THIS SHOULD LIMIT NIGHTTIME COOLING AND
FOG PRODUCTION...BUT STILL EXPECT MVFR CATEGORY FOG TO BE PREVALENT
OVERNIGHT INTO THE EARLY MORNING. EXPECT DRIER AIR TO MOVE IN FOR
FRIDAY INTO FRIDAY NIGHT. /EC/

&&

.PREV DISCUSSION... /ISSUED 237 PM CDT THU SEP 18 2014/

SHORT TERM...UPPER TROUGHING PREVAILS ACROSS THE ARKLAMISS THIS
AFTERNOON WITH AN ASSOCIATED FRONTAL BOUNDARY EXTENDING ACROSS THE
NORTHERN PORTION OF THE AREA. A SHORT WAVE IS MOVING INTO THE DELTA
AND THIS COMBINED WITH THE BOUNDARY IS THE FOCUS OF SOME AFTERNOON
THUNDERSTORM DEVELOPMENT. WITH INCREASED STABILITY AND FLOW ALOFT
SOME OF THESE STORMS HAVE BECOME STRONG TO SEVERE. EXPECT THE STORMS
TO PERSIST INTO THE EVENING HOURS...ESPECIALLY NEAR THE BOUNDARY...
BUT MOST OF THE HI-RES MODELS SUGGEST THAT THEY SHOULD DISSIPATE
BEFORE MIDNIGHT. THE SHORT WAVE WILL SHIFT TO THE SOUTH OF THE AREA
OVERNIGHT AND THIS WILL PUSH THE BOUNDARY JUST SOUTH OF THE AREA
ALSO...BRINGING IN SOME DRIER AIR ACROSS THE AREA BY FRIDAY MORNING.

WEAK UPPER RIDGING WILL BEGIN TO BUILD ACROSS THE AREA ON FRIDAY AND
THIS COMBINED WITH THE DRIER AIR WILL MAKE FOR A NICE DAY UNDER
PARTLY CLOUDY SKIES. UPPER AND SURFACE RIDGING WILL STRENGTHEN
ACROSS THE AREA ON SATURDAY AND THE RESULT WILL BE MAINLY PARTLY
CLOUDY SKIES AND HIGHS AROUND 90 DEGREES. SURFACE HIGH PRESSURE WILL
CONTINUE OVER THE AREA SATURDAY NIGHT INTO SUNDAY WITH LOWS IN THE
LOW TO MID 60S. DID NOT MAKE ANY CHANGES TO THE FORECAST PAST
SATURDAY NIGHT...SO WILL ATTACH THE APPLICABLE PORTIONS OF THE
PREVIOUS LONG TERM DISCUSSION BELOW./15/

PREVIOUS LONG TERM...BY SUNDAY, A RIBBON OF 1.5-1.6" PWATS WILL
PIVOT INTO NW/W AREAS AHEAD OF A FRONT AIDED BY STRONGER NW FLOW AS
EASTERN CONUS TROUGH AMPLIFIES SOUTH IN CONJUNCTION WITH STRONG
SURFACE HIGH IN CENTRAL PLAINS. THIS ENVIRONMENT COULD SUPPORT A FEW
WEAKLY INSTABILITY INDUCED SHOWERS.

THE NEW EC IS MORE BULLISH (AND MORE IN LINE WITH GFS) THEN PREVIOUS
RUN ON STRONGER SOUTHWARD FRONTAL MOMENTUM THROUGH REGION LATE
MONDAY INTO TUESDAY MORNING. AS FRONT MOVES THROUGH MONDAY, MOISTURE
LOOKS TO BE LACKING AND WEAK LOW-LVL CONVERGENCE WILL ALSO BE IN
PLAY. YET, FEEL SHOWERS AND A RUMBLE OF THUNDER WILL HAVE A CHANCE
TO DEVELOP AS BOUNDARY MOVES THROUGH. BEST CONCENTRATION OF RAIN
WITH CURRENT THINKING OF TIMING WILL BE ALONG AND SOUTH OF I-20
WHERE INSTABILITY WILL BE GREATER MONDAY AFTN. AT LEAST LOWER 50F
DEWPOINTS LOOK TO INFILTRATE THROUGH MOST OF REGION BY MIDDAY
TUESDAY ALONG WITH SOME CAA IN THE 925/850MB LAYERS. THESE
COMPONENTS WILL ALLOW FOR TEMPERATURES TO FALL BACK TOWARDS NORMALS
IN THE UPPER 50S/LOW 60S AND HIGHS IN THE MID 80S TUESDAY WITH
SLIGHT MODERATION WEDNESDAY AS FRONT MAY WAFFLE BACK NORTH ALONG FAR
SOUTH AREAS. /ALLEN/

&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       65  91  66  91 /  19   1   1   5
MERIDIAN      64  92  64  90 /  17   1   1   4
VICKSBURG     65  91  64  91 /  17   2   1   5
HATTIESBURG   68  92  68  91 /  33   8   4   3
NATCHEZ       67  89  67  90 /  32   7   4   3
GREENVILLE    67  90  67  92 /  24   1   1   6
GREENWOOD     66  91  66  92 /  28   1   1   5

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&

$$




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