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000
FXUS64 KJAN 171556
AFDJAN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
1056 AM CDT MON JUN 17 2013

.UPDATE...

OVERALL..,ONLY MINOR ADJUSTMENTS WERE MADE IN THIS FORECAST UPDATE.

THERE ARE TWO AREAS OF FOCUS FOR CONVECTIVE DEVELOPMENT THIS
AFTERNOON. A COMPLEX OF STORMS THAT DEVELOPED EARLY THIS MORNING
OVER NORTH CENTRAL MS HAS STABILIZED AREAS ALONG THE HIGHWAY 82
CORRIDOR. THE LATEST HRRR SUGGESTS THAT FUTURE CONVECTION WILL
DEVELOP ALONG THE DIFFERENTIAL HEATING/OUTFLOW BOUNDARY LEFT FROM
THIS COMPLEX OVER AREAS NORTH OF I-20.

THE OTHER FEATURE OF CONCERN IS THE DECAYING UPSTREAM CONVECTIVE
COMPLEX CURRENTLY CROSSING THE ARKLATEX. HIGH RES GUIDANCE SUGGEST
FURTHER DECAY OF COMPLEX WITH A RESIDUAL BOUNDARY HELPING TO INITIATE
STORMS LATER THIS AFTERNOON INTO THE EVENING. LIMITING FACTORS
HOWEVER IN ENVIRONMENT AHEAD OF THE COMPLEX ARE THE NEGATIVE LOW-LEVEL
THETAE ADVECTION INTO SOUTHERN PORTIONS OF THE ARKLAMISS...AND
RELATIVE WESTERLY FLOW AHEAD OF THE BOUNDARY THAT IS LIMITING LOW
LEVEL CONVERGENCE. WITH THIS IN MIND...STILL EXPECT GREATEST
AFTERNOON CONVECTIVE POTENTIAL FOR AREAS ALONG AND NORTH OF THE I-20
CORRIDOR AND THE GOING FORECAST HAS A GOOD HANDLE ON THE SCENARIO.
THE UPDATED AVIATION DISCUSSION IS BELOW. /EC/

&&

.PREV DISCUSSION... /ISSUED 326 AM CDT MON JUN 17 2013/

SHORT TERM...CHALLENGING CONVECTIVE FORECAST TODAY AS TIMING
SPECIFICS ARE VERY DIFFICULT DUE TO POOR REPRESENTATION OF THE
CURRENT S/WV`S AND MCV FEATURES IN THE MODEL DATA. STILL...THE
PATTERN WILL SUPPORT MULTIPLE S/WV FEATURES THROUGH TUE NIGHT AND
BRING SEVERAL OPPORTUNITIES FOR SHRA/TSRA DURING THE NEXT 48 HRS.

YESTERDAY OFFERED GREATER STORM/PRECIP COVERAGE THAN EXPECTED AND
WAS LIKELY THE KICKOFF DAY FOR THIS UPCOMING WETTER PERIOD.
ATMOSPHERIC MOISTURE SHOWED A MARKED INCREASE FROM SUNDAY MORNING TO
THE AFTERNOON AS PWS REACHED 2 IN. LOOK FOR THIS MORE MOIST AIRMASS
TO HANG AROUND WITH PWS RANGING FROM 1.75-2.0 INCHES. THIS WILL
COMBINE WITH MULTIPLE DISTURBANCES TRAVERSING THE REGION TO
INSTIGATE NUMEROUS SHOWERS AND STORMS. THE FIRST MCV JUST PUSHED
INTO AL AND WAS GENERATED BY THE AFTERNOON STORMS OVER THE WESTERN
PART OF THE CWA. EARLY THIS MORNING...A MCV IS PUSHING EAST ACROSS
CENTRAL AR AND WILL LIKELY AID IN PRECIP ACTIVITY THIS
MORNING/AFTERNOON. THERE IS ALSO A MUCH LARGER DISTURBANCE PUSHING
ACROSS OK AND THIS WILL TOO HELP SUPPORT CONVECTION LATER IN THE
AFTERNOON/EVE ESPECIALLY ACROSS THE W/NW AREAS. IF THAT WASN`T
ENOUGH...ADDITIONAL DISTURBANCES ARE PROGGED TO CONTINUE IN THE
PERTURBED FLOW AND SUPPORT ADDITIONAL CONVECTION THROUGH TUE. AT
THIS TIME...WILL CONTINUE TO BE GENERAL WITH TIMING DUE TO THE
UNCERTAINTY WITH HOW EACH FEATURE WILL EVOLVE AND FOLLOW CLOSE TO
THE HIGHER GUIDANCE POPS. FOR TODAY...I CURRENTLY HAVE THE BEST
PRECIP CHANCES FOR THE AFTERNOON...BUT THIS MAY HAVE TO BE REVISITED
BASED ON HOW STORM TRENDS THIS MORNING GO.

TODAY SEEMS TO HAVE A POTENTIAL FOR STRONG STORMS ALONG WITH A FEW
SEVERE STORMS MIXED IN. THE REASON IS THAT SOME WARMER SFC TEMPS MAY
BE REALIZED AS HIGHS PEAK AROUND 90 WHICH COULD RESULT IN NEAR 3000
J/KG OF SBCAPE. THERE WILL ALSO BE SOME COOLER MID LEVEL TEMPS ALONG
WITH SOME STRONGER FLOW (25-30KTS) AT 500MB WHICH SHOULD HELP
SUPPORT A FEW VIGOROUS UPDRAFTS. DUE TO THIS...WILL MENTION THIS
POTENTIAL IN THE HWO/GRAPHICS. THE MAIN THREAT WILL BE FROM GUSTY
WINDS 50-60 MPH AND SMALL HAIL. YESTERDAY...LIGHTNING WAS ALSO
FREQUENT WITH THE STRONGER STORMS AND THAT MAY AGAIN BE THE CASE.
/CME/

LONG TERM...WEDNESDAY THROUGH NEXT MONDAY...A RATHER ACTIVE
PATTERN CONTINUES ACROSS THE FORECAST AREA AS NORTHWEST FLOW
PERSISTS INTO AT LEAST THURSDAY...WHILE SUBTLE UPPER LEVEL
DISTURBANCES IMPEDE UPON THE CWA ALONG A QUASI-STATIONARY SURFACE
BOUNDARY.  AN UPPER RIDGE WILL BUILD EAST INTO THE FORECAST AREA
FRIDAY INTO THE WEEKEND.  CHANCES FOR MAINLY AFTERNOON AND EARLY
EVENING SHOWERS AND STORMS WILL REMAIN OVER PARTS OF THE FORECAST
AREA DURING THIS TIME AND INTO NEXT MONDAY.  CONVECTION FRIDAY
THROUGH MONDAY IS EXPECTED TO BE MORE DIURNALLY DRIVEN AND ISOLATED
TO SCATTERED IN NATURE COMPARED TO THE MORE ORGANIZED CONVECTION
SEEN EARLIER IN THE WORK WEEK.

OTHERWISE...WARM AND VERY HUMID CONDITIONS WILL PERSIST THROUGH THE
ENTIRE PERIOD.  HIGHS EACH AFTERNOON WILL RANGE IN THE LOW TO MIDDLE
90S.  GUIDANCE SUGGESTED AS THE RIDGE BUILT IN FRIDAY...HIGHS COULD
RANGE FROM 95-97.  GIVEN EXPECTED WET GROUND CONDITIONS DURING THIS
TIME...FELT THESE WERE TOO HIGH.  THEREFORE I KNOCKED OFF 2-3
DEGREES AND NOW HAVE HIGHS RANGING FROM 92-94 ON FRIDAY.  ELSEWHERE
THROUGH THE PERIOD...BOTH GUIDANCE HIGH AND LOW TEMPERATURES LOOKED
REASONABLE. /19/

&&

.AVIATION...CONDITIONS WILL GENERALLY BE VFR VFR TODAY...THE
EXCEPTION BEING MVFR CIGS/VSBYS...LCLY IFR VSBYS...WHERE SHWRS/TSTMS
OCCUR. AN AREA OF LATE MORNING SHWRS/TSTMS EXISTS OVER NRN/NERN
ZONES DURING THE LATE MORNING/EARLY AFTERNOON. THE FOCUS WILL SHIFT
TO SCT SHWRS/TSTMS FOR THE REMAINDER OF THE REGION DURING THE
AFTERNOON. FOR TONIGHT...THERE LOOKS TO BE SOME LINGERING STORM
CHANCES OVERNIGHT AND SOME RISK FOR SOME MVFR CONDITIONS FOR THE
AREAS THAT RECEIVED PRECIP. /CME/03

&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       92  71  89  70 /  36  42  49  50
MERIDIAN      91  70  89  69 /  49  47  57  57
VICKSBURG     92  72  89  70 /  29  45  50  47
HATTIESBURG   92  72  91  72 /  36  23  36  31
NATCHEZ       90  71  89  70 /  26  25  37  32
GREENVILLE    91  73  87  70 /  51  67  66  40
GREENWOOD     90  71  88  69 /  54  66  68  41

&&

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

&&

$$