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000
FXUS64 KJAN 191536 AAA
AFDJAN

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
1036 AM CDT WED JUN 19 2013

.UPDATE...
A WEAK AND STALLED FRONTAL BOUNDARY WILL BE THE MAIN FOCUS THIS
AFTERNOON FOR SOME SHOWERS/THUNDERSTORM ACTIVITY. THIS BOUNDARY WILL
SLOWLY DRIFT TO THE SOUTH THROUGHOUT THE DAY. WATER VAPOR ANALYSIS
INDICATES A S/WV AND TROUGH AXIS MOVING THROUGH THE ARKLAMISS DELTA.
THE ENHANCED SYNOPTIC LIFT AND AIDED WITH CONVERGENCE ALONG THE
STALLED FRONTAL BOUNDARY WILL AID IN SHOWER/THUNDERSTORM DEVELOPMENT
THIS AFTERNOON TO EVENING. WENT CLOSE TO MAV POPS AS HRRR WAS
INDICATING MOST ACTIVITY ALONG AND S OF THE I-20 CORRIDOR...MAINLY
IN THE SE...AND WEAKENING AFTER 00Z. WEAK LAPSE RATES AND VERTICAL
TOTALS AROUND 25-26C WILL AID IN SOME THUNDERSTORM DEVELOPMENT BUT
NOT EXPECTING MUCH IN THE WAY OF STRONG STORMS. TEMPS TODAY LOOK TO
BE RUNNING ON TRACK AND DID NOT MODIFY HIGH TEMPS THIS AFTERNOON.
ONLY MODIFIED HOURLY TEMPS/DEWPOINTS ACCORDING TO CURRENT TRENDS.
ALSO MODIFIED CLOUD COVER GRIDS TO ONLY SLIGHTLY SPEED UP SOUTHWARD
PROGRESSION OF CLOUD COVER. REST OF THE FORECAST IS ON TRACK. /DC/

&&

.AVIATION...MVFR CIG AT A FEW LOCALES WILL TREND VFR BY LATE MORNING
W/VFR CONDS PERSISTING THRU THE REMAINDER OF THE DAY. NUMEROUS SHRA
WILL IMPACT SE MS OVER THE NEXT FEW HRS BEFORE MORE ISOLD ACTIVITY
TAKES SHAPE THIS AFTN. ELSEWHERE ISOLD SHRA WILL BE PSBL THIS
MORNING DECLINING IN COVERAGE THRU THE AFTN. MVFR/IFR CIG AND PSBLY
VSBY CAN BE XPCTD AT HBG/MEI AND PSBLY JAN/HKS TOMORROW MORNING
10-14Z. /BK/

&&

.PREV DISCUSSION... /ISSUED 340 AM CDT WED JUN 19 2013/

SHORT TERM...THE FOCUS OF THE FORECAST WILL CONTINUE TO REVOLVE
AROUND PRECIP CHANCES...ESPECIALLY FOR TODAY AND THU...BUT THESE
CHANCES WILL OVERALL LESS THAN WHAT THE AREA HAS SEEN THE PAST
COUPLE DAYS. ONE OF THE KEY FEATURES THAT WILL INFLUENCE OUR WEATHER
IS THE STALLED WEAK SFC FRONT ACROSS THE AREA. THIS BOUNDARY HAS
BECOME BROAD/DIFFUSE...BUT IS GENERALLY SITUATED FROM TUP TO MLU.
WHILE IT WOULD SEEM THAT AREAS ALONG AND SOUTH OF SAID BOUNDARY
WOULD HAVE THE BEST PRECIP POTENTIAL TODAY...THIS NOT TRULY THE
CASE. THE REASON IS THAT SOME DRIER AIR IN THE MID LEVELS IS PRESENT
FOR AREAS JUST NORTH OF I-20. THIS IS IN PART TO NORTHERLY MID LEVEL
FLOW DRAWING SOUTHWARD THAT DRIER AIR AS THE S/WV PASSED ACROSS THE
SOUTHERN PARTS OF THE FORECAST AREA LAST EVENING. WITH ALL OF
THIS...AREAS ALONG AND SOUTH OF I-20 WILL HAVE THE DEEPEST MOISTURE
TO WORK WITH TODAY ALONG WITH SOME LOW LEVEL FOCUS FROM THE STALLED
SFC BOUNDARY. ADDITIONALLY...WATER VAPOR IMAGERY SHOWS THE MID/UPPER
TROUGH AXIS QUITE WELL AND IT IS SITUATED JUST TO OUR WEST. THIS
FEATURE SHOULD ASSIST LIFT (ESP THIS MORNING) AND GENERATE PRECIP
ACROSS THE SOUTHERN HALF OF THE AREA. THINKING THAT THE AIRMASS HAS
BEEN WORKED OVER QUIET A BIT...OVER ALL LESS STORM COVERAGE IS
EXPECTED. THUS...FOLLOWING THE 20-40% POPS FROM THE GFS SEEM VALID.
WITH ANOTHER EARLY START TO ACTIVITY...WILL TREND POPS/WX DOWN FOR
THE LATE AFTERNOON.

LIKE YESTERDAY...TEMPS WILL BE HELD IN CHECK THANKS TO CLOUDS AND
THE EARLY START TO PRECIP. GFS GUIDANCE INDICATES THIS WELL AND HAVE
FOLLOWED. TONIGHT WILL BE GENERALLY QUIET WITH CLEARINGS SKIES.
TEMPS WILL BE A BIT COOLER THAN WHAT WE HAVE SEE WITH UPPER 60S
EXPECTED.

THURSDAY WILL BE A TRICKIER FORECAST AS THE PREV MENTIONED SFC
BOUNDARY WILL STILL BE IN THE GENERAL AREA BUT LIKELY
SITUATED/ORIENTED IN A DIFFERENT MANNER. DEEP MOISTURE WILL BE
OVERALL LOWER AREAWIDE WITH HIGHER MOISTURE CONTENT GENERALLY ACROSS
THE SW/S HALF. WHAT MAKES THE FORECAST TRICKY IS THE PRESENCE OF A
DISTINCT S/WV DROPPING SE. ASSOCIATED WITH THIS FEATURE WILL BE
COOLER TEMPS IN THE MID LEVEL AND ALOFT. THE MID/UPPER LEVEL JET
WILL ALSO BE SITUATED IN A WAY THAT SUPPORTS UPWARD MOTION. EVEN AS
THESE FAVORABLE FEATURES EXIST...MODEL DATA IS NOT SHOWING MUCH
DEVELOPMENT. I CAN`T ARGUE THAT THERE WILL BE LESS OVERALL
POTENTIAL...BUT FEEL THAT ENOUGH INGREDIENTS WILL EXIST THAT
ISOLATED STORMS WILL BE POSSIBLE DURING THE AFTERNOON. WITH
THAT...HAVE INCREASED POPS FROM 10% TO 20% AND MENTIONED SLIGHT
CHANCE FOR AFTERNOON ACTIVITY. AT THIS TIME...I WILL NOT MENTION ANY
POSSIBILITY FOR STRONG STORMS...BUT THIS WILL HAVE TO BE MONITORED
AS THE COOLER TEMPS ALOFT WILL LEAD TO BETTER LAPSE RATES AND A BIT
HIGHER INSTABILITY AS SFC TEMPS WILL BE 2-4 DEGREES WARMER. /CME/

LONG TERM...FRIDAY THROUGH NEXT WEDNESDAY...AN UPPER RIDGE WILL
TRY BUILDING INTO THE WESTERN HALF OF THE FORECAST AREA FRIDAY INTO
THE WEEKEND AS AN UPPER TROUGH PULLS OFF TO THE NORTHEAST AND UP THE
EAST COAST.  AS THIS HAPPENS...THE TROUGH WILL LEAVE BEHIND A PIECE
OF ENERGY THAT`LL SET THE STAGE FOR SOME ISOLATED TO SCATTERED
AFTERNOON AND EARLY EVENING SHOWERS AND STORMS OVER MAINLY EAST AND
SOUTHEAST MISSISSIPPI THROUGH THE WEEKEND.  RAIN CHANCES LOOK TO
WANE HEADING INTO THE NEW WORK WEEK AS THE UPPER RIDGE BUILDS
FURTHER EAST INTO THE CWA.

OTHERWISE...LOOK FOR CONTINUED HOT AND HUMID CONDITIONS THROUGH THE
FORECAST PERIOD.  GUIDANCE SUGGESTED HIGHS AND LOWS LOOK REASONABLE
THIS MORNING.  HIGHS EACH AFTERNOON WILL RANGE IN THE LOW TO MID
90S...WHILE LOWS EACH NIGHT GENERALLY RANGE FROM THE UPPER 60S TO
LOWER 70S.  /19/

&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       89  66  91  69 /  25   9  17   6
MERIDIAN      87  64  91  68 /  27  12  15  12
VICKSBURG     88  64  91  68 /  21   7  17   4
HATTIESBURG   87  68  92  69 /  40  24  23  12
NATCHEZ       87  67  90  68 /  34   9  23   6
GREENVILLE    90  68  94  70 /   6   4   7   3
GREENWOOD     90  65  93  68 /   7   4   5   5

&&

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

$$

DC/BK/CME/19