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000
FXUS64 KMEG 160833
AFDMEG

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
333 AM CDT THU MAY 16 2013

.DISCUSSION...

SKIES WERE GENERALLY CLOUDY ACROSS THE MIDSOUTH WITH A FEW
ISOLATED PATCHES OF LIGHT RAIN. WINDS WERE OUT OF THE SOUTH AND
UNDER 10 KTS...WHILE TEMPERATURES RANGED FROM THE MID 60S TO THE
LOW 70S. SATELLITE INDICATED APPROACHING CLOSED LOW CENTERED OVER
CENTRAL OKLAHOMA WITH LINE OF AFTERNOON GENERATED CONVECTION STILL
SURGING SOUTHEAST ACROSS EAST TEXAS.

FOR TODAY THROUGH SATURDAY...MODELS CONTINUE TO AGREE THAT THE
CLOSED LOW/DISTURBANCE WILL SLOWLY TRACK EAST...AND BECOME MORE
DIFFUSE AS THE CIRCULATION TRANSITIONS TO AN OPEN WAVE. DESPITE
THIS...THE 00Z RUNS ARE INDICATING MORE QPF FOR THE
AREA...ESPECIALLY FRIDAY AND FRIDAY NIGHT...AND ALONG AND SOUTH
OF INTERSTATE FORTY. HAVE AGREED ON THIS THINKING AND HAVE BUMPED
UP RAIN CHANCES STARTING TONIGHT. OTHER INTERESTING NOTE IS THE
LATEST DAY TWO SEVERE OUTLOOK SHOWING A SLIGHT RISK OVER
SOUTHWEST TENNESSEE AND NORTH MISSISSIPPI FOR FRIDAY. BELIEVE THIS
MAY BE OVERDONE FOR THE FOLLOWING REASONS...SHEAR IS WEAKENING
...A LONGER PERIOD OF SHOWERS WILL ONLY GENERATE CAPE VALUES IN
THE 500 J/KG-1000 J/KG RANGE WITH CONTINUED LONG SKINNY CAPE
PROFILES...LAST LIFT FROM THE LOW IS WEAKENING SO STORMS WILL BE
DISORGANIZED. FOR NOW WILL CONTINUE WITH AN ISOLATED STRONG
STORM ACROSS THE AREA IN THE FUTURE HWO.

HAVE ALSO INCREASED POPS SLIGHTLY OVER THE EAST ON SATURDAY AS
THIS REGION WILL STILL BE UNDER WEAK TROUGHING. HAVE LOWERED HIGH
TEMPERATURES A DEGREE OR TWO THROUGH THIS PERIOD.

SUNDAY AND MONDAY...THE GFS AND EURO INDICATE A STRONGER TROUGH
WILL CROSS THE ROCKIES...BUILDING THE DOWNSTREAM RIDGE OVER THE
PLAINS AND MISSISSIPPI VALLEY. FORECAST SOUNDINGS SHOW
TEMPERATURES APPROACHING 90F ALONG WITH CAPE AMOUNTS IN EXCESS OF
3000 J/KG. THEY ALSO INDICATE A 2-3C CAP DEVELOPING. THUS HAVE
REMOVED THE POPS DURING THIS TIME FRAME. AS THE TROUGH MOVES INTO
THE UPPER HIGH PLAINS MONDAY...A SURFACE LOW IS EXPECTED TO
OCCLUDE IN THE DAKOTAS WITH A TRAILING COLD FRONT BECOMING MORE
ACTIVE IN THE LOWER MISSOURI RIVER VALLEY. THIS CONVECTION COULD
EASILY CONTINUE DURING THE NIGHT AS THE LLJ INTENSIFIES REACHING
THE NORTHERN COUNTIES BY DAWN TUESDAY. HEAT INDICES BOTH DAYS
WILL RUN IN THE LOW TO MID 90S.

TUESDAY AND WEDNESDAY...THE EURO AND GFS PAINT NEARLY THE SAME
PICTURE AS FAR AS THE COLD FRONT STALLING OVER THE MIDSOUTH AND
FIZZLING. CONVECTION CHANCES WILL CONTINUE BOTH DAYS WITH A RISK
FOR A FEW STRONG OR POSSIBLY SEVERE STORMS. THE MAIN DIFFERENCES
IN THE MODELS ARE IN REGARDS TO THE UPPER LEVEL SUPPORT. THE EURO
CONTINUES TO TRACK THE CLOSED LOW FROM THE DAKOTAS SOUTHEAST TO
THE OHIO VALLEY AS AN UPPER LEVEL RIDGE BUILDS FURTHER WEST. THE
GFS ON THE OTHER HAND TAKES THE CLOSED LOW EAST ACROSS THE GREAT
LAKES AND TRANSITIONS IT TO AN OPEN WAVE. THE EURO SCENARIO WOULD
LIKELY CREATE A BETTER THREAT FOR SEVERE WEATHER IN THE AREA.
SINCE THIS DISAGREEMENT IS WELL OFF IN THE FUTURE...WILL LEAVE OUT
ANY MENTION OF THE SEVERE POTENTIAL IN THE HWO. TEMPERATURES THIS
PERIOD WILL ONLY COOL SLIGHTLY FROM SUNDAY AND MONDAY.

JAB

&&

.AVIATION...

06Z TAF CYCLE

VFR CONDITIONS GENERALLY EXPECTED THROUGH THE PERIOD. A FEW SHRAS
COULD EFFECT AREAS ALONG AND WEST OF THE MISSISSIPPI RIVER THROUGH
12Z INCLUDING KMEM AND KJBR. PLAN TO CARRY VCSH ALONG WITH TEMPO FOR
SHOWERS AT KJBR AND KMEM THROUGH 11/12Z. CHANCES FOR TSRAS WILL
AGAIN OCCUR AFTER 18Z ACROSS ALL OF THE MIDSOUTH DUE TO THE
PROXIMITY OF THE UPPER LEVEL LOW. WILL INTRODUCE VCTS AT ALL TAF
SITES AND WILL CONTINUE THROUGH EVENING AS UPPER LEVEL LOW IS
FORECAST TO MOVE OVER THE MIDSOUTH BY TOMORROW NIGHT. SSW WINDS WILL
INCREASE TO 8-12 KTS AFTER 15Z WITH HIGHER GUSTS.

KRM/JLH

&&

.PRELIMINARY POINT TEMPS/POPS...
MEM  81  67  82  70 /  30  50  50  30
MKL  80  64  80  66 /  20  50  50  30
JBR  78  64  80  67 /  40  50  50  20
TUP  81  65  82  67 /  30  50  50  30

&&

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

$$