Severe Thunderstorm Warning 124, NWS Memphis, TN

398 
WWUS54 KMEG 211942
SVSMEG

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MEMPHIS TN
242 PM CDT TUE JUN 21 2016

TNC131-183-211952-
/O.EXP.KMEG.SV.W.0124.000000T0000Z-160621T1945Z/
WEAKLEY TN-OBION TN-
242 PM CDT TUE JUN 21 2016

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN WEAKLEY AND
NORTHEASTERN OBION COUNTIES WILL EXPIRE AT 245 PM CDT...
                
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 3628 8877 3639 8921 3651 8917 3650 8868
TIME...MOT...LOC 1939Z 277DEG 7KT 3650 8907 

$$

Area Forecast Discussion
National Weather Service Memphis TN
106 PM CDT TUE JUN 21 2016

.UPDATE...
Updated to add the 18Z Aviation Discussion.

&&

.PREV DISCUSSION... /issued 936 AM CDT TUE JUN 21 2016/

UPDATE...

Update to remove mention of morning pops across the forecast area.

DISCUSSION...

The upper level height ridge that has been over the region for the
past few days has retrograded westward and left much of the Mid
South beneath a northwest flow regime aloft. A subtle disturbance
upstream across Missouri this morning will advance southeastward
and bring scattered showers and thunderstorms to mainly northwest
Tennessee this afternoon. This area will be grazed by faster mid
level flow aloft which may support organized convection later this
afternoon across these locations. In addition...an increasingly
unstable atmosphere should be in place with MLCAPES in excess of
3500 j/kg along with LI/s to -10c. The only unfavorable
instability parameter will be rather weak mid level lapse rates.
Therefore...will continue with the mention of isolated severe
storms this afternoon over these locations.

Updates to the latest products have been sent out.

JLH

PREV DISCUSSION... /issued 246 AM CDT TUE JUN 21 2016/

DISCUSSION...
Blow off mid to high clouds from convection occurring across Missouri
with a back door cold front will continue to spread across the
Mid-South over the next couple of hours. Some of the showers
and thunderstorms may make it down into portions of Northeast
Arkansas, the Missouri Bootheel, and extreme Northwest Tennessee
before dying out this morning. Models are not initializing
particularly well with this convection especially the NAM. The
big question will be how long it takes for the mid/high clouds to
thin out. If the clouds hang on a good part of the day, it could
keep highs a tad cooler as well as limit any pop up diurnal
convection. Expect the best chance for rain will occur across
portions of West Tennessee this afternoon from convection that
develops ahead of the approaching back door cold front. Will
lower highs a tad across West Tennessee.

The front will make it as far south as Western Kentucky this
evening before lifting back to the north as the upper ridge
strengthens over the Mid-South. Wednesday will be hot with highs
in the mid 90s. Heat indices may reach into the 100 to 105 degree
range during the afternoon and evening. The ridge also should be
strong enough to prevent any diurnal convection from developing.

By Thursday, the ridge begins to retreat to the south allowing another
back door cold front to approach from the northeast.
Some convection ahead of the front could move into northern
portions of the CWA by midday. Better chances will Thursday
evening moves into the vicinity of the KY/TN border. Again, heat
INDICES could reach into the 100 to 105 degree range on Thursday
especially if higher dewpoints pool ahead of the back door cold
front.

The front begins to lift back to the north on Friday as the ridge
re-intensifies over the Mid-South. Both Saturday and Sunday look
hot with highs in the mid 90s as the ridge will be centered over
the area. Expect little if any diurnal convection over the weekend
as a result.

By Monday, the ridge may begin to retreat to the south and west
again.

KRM

&&

.AVIATION...

VFR conditions are expected throughout the 24 hour TAF period. As
of 18Z, a few isolated showers have begun to form along a MS River
along a weak frontal boundary. These showers are expected to
remain isolated in coverage and shouldn't impact any TAF site.
However, based on NAM guidance, added VCTS to account for
thunderstorm development near KMKL later this afternoon. Winds
will be from the east early in the period before switching to the
south.

&&

.MEG Watches/Warnings/Advisories...
AR...None.
MO...None.
MS...None.
TN...None.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MEMPHIS TN
436 AM CDT TUE JUN 21 2016

ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-
MSZ001>017-020>024-TNZ001>004-019>022-048>055-088>092-221200-
ALCORN-BENTON MS-BENTON TN-CALHOUN-CARROLL-CHESTER-CHICKASAW-CLAY-
COAHOMA-CRAIGHEAD-CRITTENDEN-CROCKETT-CROSS-DESOTO-DECATUR-
DUNKLIN-DYER-FAYETTE-GIBSON-GREENE-HARDEMAN-HARDIN-HAYWOOD-
HENDERSON-HENRY-ITAWAMBA-LAFAYETTE-LAKE-LAUDERDALE-LAWRENCE-
LEE AR-LEE MS-MADISON-MARSHALL-MCNAIRY-MISSISSIPPI-MONROE-OBION-
PANOLA-PEMISCOT-PHILLIPS-POINSETT-PONTOTOC-PRENTISS-QUITMAN-
RANDOLPH-SHELBY-ST. FRANCIS-TALLAHATCHIE-TATE-TIPPAH-TIPTON-
TISHOMINGO-TUNICA-UNION-WEAKLEY-YALOBUSHA-
436 AM CDT TUE JUN 21 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST ARKANSAS...
THE MISSOURI BOOTHEEL...NORTH MISSISSIPPI...AND WEST TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

ISOLATED STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE OVER
NORTHWEST TENNESSEE TUESDAY AFTERNOON. DAMAGING WINDS...HAIL AND
LOCALLY HEAVY RAINFALL WILL BE THE PRIMARY THREATS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

HEAT INDEX READINGS MAY REACH 100 TO 105 DEGREES WEDNESDAY
AND THURSDAY AFTERNOONS ACROSS THE ENTIRE MIDSOUTH.

ISOLATED STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE OVER
NORTHWEST TENNESSEE THURSDAY AFTERNOON AND EVENING. DAMAGING
WINDS...HAIL AND LOCALLY HEAVY RAINFALL WILL BE THE PRIMARY
THREATS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME.

KRM