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000
FXUS64 KMEG 170518
AFDMEG

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
1218 AM CDT MON JUN 17 2013

.UPDATE...
UPDATED FOR 06Z AVIATION DISCUSSION.

&&

.PREV DISCUSSION... /ISSUED 910 PM CDT SUN JUN 16 2013/

DISCUSSION...WATER VAPOR SATELLITE/UPPER AIR PROFILERS/WSR-88D
VAD WIND PROFILES INDICATE SEVERAL 500 MB MID LEVEL SHORTWAVES
EMBEDDED WITHIN NEARLY ZONAL FLOW ALOFT ACROSS THE
CENTRAL/SOUTHERN PLAINS AND MIDDLE/LOWER MISSISSIPPI VALLEYS THIS
EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE MID SOUTH
DISSIPATED A FEW HOURS AGO WITH THE MOST OF THE CONVECTIVE ACTIVITY
THIS EVENING OCCURRING ACROSS PORTIONS OF OKLAHOMA...MISSOURI...ARKANSAS...AND
TEXAS. TEMPERATURES AS OF 8 PM CDT RANGE FROM THE LOWER TO MIDDLE
80S WEST OF THE MISSISSIPPI RIVER...AND 70S TO LOWER 80S EAST.
SHOWER AND THUNDERSTORM POTENTIAL FOR THE REMAINDER OF THE NIGHT
REMAINS THE PREDOMINANT FORECAST CHALLENGE.

00Z KLZK UPPER AIR SOUNDING STILL REMAINS QUITE UNSTABLE WITH
SURFACE BASED CAPE VALUES AROUND 3200 J/KG...LI/S AROUND -8...AND
VERY LITTLE CONVECTIVE INHIBITION. INSTABILITY AT KJAN REMAINS
SIMILAR WITH MUCH MORE LOW LEVEL MOISTURE PRESENT THAN LZK.
MEANWHILE...INSTABILITY IS LOWER AT OHX THIS EVENING. 18Z MODELS
AND THE 00Z NAM ARE NOT HANDLING THE CURRENT CONVECTIVE ACTIVITY
PARTICULARLY WELL. THE LATEST RAPID REFRESH /HRRR/ INDICATES THE
BEST POTENTIAL FOR SHOWER/THUNDERSTORM ACTIVITY WILL REMAIN MAINLY
ALONG AND WEST OF THE MISSISSIPPI RIVER OVERNIGHT. AN ISOLATED
STRONG TO PERHAPS SEVERE THUNDERSTORM MAY BE POSSIBLE FOR THE NEXT
FEW HOURS MAINLY WEST OF THE MISSISSIPPI RIVER. OTHERWISE...OVERALL
POTENTIAL REMAINS LOW AT THIS TIME.

BASED ON THE LATEST TRENDS WILL LOWER POPS SLIGHTLY ACROSS
EASTERN SECTIONS OF THE FORECAST AREA AND KEEP ONGOING CHANCE POPS
ALONG AND WEST OF THE MISSISSIPPI RIVER. WILL ALSO ADJUST
TEMPERATURES...CLOUD COVER...AND ALL OTHER ELEMENTS AS NEEDED TO
ACCOUNT FOR SHORT TERM TRENDS. OTHERWISE...FORECAST OVERALL IS IN
GOOD SHAPE.

UPDATED GRIDS WILL BE AVAILABLE SHORTLY.

CJC

&&

.PREV DISCUSSION... /ISSUED 620 PM CDT SUN JUN 16 2013/

UPDATE...AVIATION DISCUSSION.

PREV DISCUSSION... /ISSUED 318 PM CDT SUN JUN 16 2013/

DISCUSSION...

WET PATTERN SETTING OVER THE MIDSOUTH OVER THE NEXT COUPLE OF
DAYS AS A COLD FRONT AND SEVERAL SHORTWAVES MOVE INTO THE REGION.

TONIGHT...VERY LOW CONFIDENCE ON WHAT WILL HAPPEN AS MODELS DID
NOT INITIALIZE VERY WELL. ABUNDANCE OF CLOUD COVER OVER THE REGION
HAS KEPT THE ATMOSPHERE MORE STABLE THAN WHAT THE MODELS WERE
INDICATING. THUS THE NAM AND RAP MODELS SHOWED NUMEROUS SHOWERS
AND THUNDERSTORMS DEVELOPING THIS AFTERNOON INTO THE EVENING HOURS
DUE TO THE COMBINATION OF PEAK HEATING AND THE EXPECTED UNSTABLE
ATMOSPHERE. THIS IS NOT THE CASE AT LEAST SO FAR. HOWEVER...WITHIN
THE LAST 45 MINUTES A THUNDERSTORM HAS DEVELOPED OVER PANOLA
COUNTY. THE NAM AND RAP SHOWED WHATEVER ACTIVITY DEVELOPED DYING
OUT AFTER SUNSET. MEANWHILE...OTHER MODELS LIKE THE HRRR SHOWED
DEVELOPMENT ALONG AND AHEAD OF AN OUTFLOW BOUNDARY WHICH IS DRAPED
ACROSS SOUTHERN MISSOURI. BEGINNING TO SEE DEVELOPMENT OCCUR ALONG
THE BOUNDARY BUT NOTHING AHEAD OF IT YET OTHER THAN A FEW SHOWERS.
THE HRRR BRINGS THE ACTIVITY INTO NORTHERN PORTIONS OF THE
MIDSOUTH THIS EVENING AND THEN DISSIPATES IT BY MIDNIGHT. IN
ADDITION...THE GFS AND ECMWF SHOWED LITTLE ACTIVITY OCCURRING THIS
EVENING. IN FACT...THE ECMWF SHOWED LITTLE ACTIVITY THE ENTIRE
NIGHT. HOWEVER...THE GFS AND THE NAM BOTH SHOW REDEVELOPMENT OF
SHOWERS AFTER MIDNIGHT...POSSIBLY DUE TO A WEAK LOW LEVEL JET.
WITH SUCH A WIDE RANGE OF SCENARIOS...HAVE KEPT 40 POPS ACROSS
FROM THE TENNESSEE/MISSISSIPPI LINE NORTHWARD MAINLY DUE TO THE
CONVECTION YOU SEE BEGINNING TO DEVELOP ALONG THE OLD OUTFLOW
BOUNDARY. THINK THIS CONVECTION WILL PUSH DOWN INTO NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL...AND NORTHWEST TENNESSEE. MAY
ALSO SEE A FEW MORE POP UP DIURNAL THUNDERSTORMS ACROSS NORTH MISSISSIPPI. DON/T
KNOW IF ANY STORM WILL BE SEVERE BUT WILL KEEP THE STRONG TO
SEVERE WORDING IN THE HWO FOR NOW. LOWS WILL BE IN THE LOWER TO
MID 70S.

MONDAY...A STRONGER SHORTWAVE WILL MOVE INTO THE REGION AS A COLD
FRONT SLIDES SOUTH INTO THE CWA. THE COMBINATION OF THE TWO SHOULD
PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE CWA. CLOUD
COVER MAY AFFECT INSTABILITY LIKE IT DID TODAY BUT CAN/T RULE OUT
A FEW STORMS BECOMING STRONG TO SEVERE. ISOLATED HEAVY RAINFALL
UNDERNEATH SLOW MOVING STORMS MAY BE A BIGGEST ISSUE WITH ANY
THUNDERSTORMS THAT OCCUR TOMORROW. THE ACTIVITY WILL CONTINUE INTO
MONDAY NIGHT AND TUESDAY AS THE COLD FRONT SLIDES SOUTHWARD. HIGHS
ON MONDAY AND TUESDAY WILL BE IN THE 80S DUE TO THE CLOUD COVER
AND AMOUNT OF CONVECTION AROUND.

TUESDAY NIGHT INTO WEDNESDAY....THE GFS SLIDES THE FRONT SOUTH OF THE
CWA WHILE THE ECMWF CONTINUES TO HOLD THE FRONT UP OVER NORTH
MISSISSIPPI. BOTH THE GFS/ECMWF ARE CONSISTENT WITH THEIR
SOLUTIONS AND ITS REALLY ANYBODY/S GUESS WHICH IS CORRECT. FOR NOW
WILL CONTINUE WITH CURRENT FORECAST WHICH LEANS TOWARD THE GFS.

THURSDAY AND FRIDAY...UPPER RIDGE BEGINS TO START MOVING BACK INTO
THE AREA FROM THE WEST. SOME DIURNAL CONVECTION COULD OCCUR ON
THURSDAY. OTHERWISE...WARMER TEMPERATURES WILL RETURN WITH HIGHS
IN THE UPPER 80S TO LOWER 90S.

NEXT WEEKEND...HOT AND DRY CONDITIONS ARE EXPECTED AS THE UPPER
RIDGE WILL BE CENTERED OVER THE MIDSOUTH. HIGHS WILL BE IN THE
LOWER TO MID 90S WITH LOWS IN THE 70S.

KRM

&&

.AVIATION...

06Z TAF CYCLE

VFR CONDITIONS WILL PREVAIL THROUGH THIS TAF PERIOD. ONLY ONE STORM
COMPLEX IS OF CONCERN ON THE RADAR...IT MAY IMPACT MEM BETWEEN 09
AND 11Z...BUT CONFIDENCE IS LOW THAT IT WILL -1 STAY TOGETHER...AND
-2 MAINTAIN ITS EASTWARD TRACK.  IT IT DOES AN HOUR OR TWO OF MVFR
TO IFR VIS CAN BE EXPECTED ALONG WITH TEMPORARY GUSTY WINDS...MOST
LIKELY FROM THE WEST. REMOVED MENTION OF TS AT ALL OTHER SITES FOR
THE REMAINDER OF THE NIGHT.  WINDS WILL BE LIGHT AND VARIABLE DUE TO
MULTIPLE OUTFLOW BOUNDARIES ACROSS THE MIDSOUTH...BUT GENERALLY FROM
THE SOUTH. TOMORROW...THUNDERSTORM COVERAGE WILL INCREASE AGAIN BY
MIDDAY. INCLUDED VCTS AT ALL SITES. INDIVIDUAL STORMS WILL REDUCE
VIS AND MAY RESULT IN STRONG GUSTY WINDS...BUT PREVAILING CONDITIONS
WILL REMAIN VFR. COVERAGE AND INTENSITY OF STORMS SHOULD DIMINISH
AFTER SUNSET.

&&

.PRELIMINARY POINT TEMPS/POPS...
MEM  71  86  71  88 /  80  40  10  10
MKL  69  85  64  87 /  80  30  10  10
JBR  69  87  67  87 /  40  10  10  10
TUP  72  84  68  88 /  70  60  10  10

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&

$$