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Area forecast discussion 
National Weather Service Memphis Tennessee
645 PM CDT Monday may 25 2015


Updated for 00z aviation discussion


Previous discussion... /issued 326 PM CDT Monday may 25 2015/

We remain in a very active pattern despite a current temporary
lull in activity. The atmosphere has recovered nicely along and
west of the Mississippi River...with rapid destabilization farther
east across the remainder of the midsouth. Laps instability
parameters feature convective available potential energy as high as 2000 j/kg in east
Arkansas...with lifted indice's as low as -4.5c. By sunset...expect to see
similar values across most of the midsouth. Well upstream over
North Texas...a bowing line of thunderstorms is shifting to the
east. Guidance suggests this feature will maintain significant
strength as it moves into the midsouth around midnight tonight. A
negatively tilted shortwave trough will become oriented from north
central Arkansas...into north central Mississippi by midnight
tonight. Surface dew points will remain in the middle to upper
60s. As a result...instability overnight will likely remain
elevated...likely as high as it is this evening. As the Bow
accelerates to the east...straight line wind damage looks
possible...if not likely...along with severe hail. Tornadoes will
also be possible...embedded in the line...most likely in
association with any kinks in the line. Additionally...although
not highly expected...isolated supercells may develop ahead of the
Bow posing a higher risk of tornadoes. The threat of severe
thunderstorms should diminish by midday tomorrow.

Flash flooding is also a concern...and may become the
primary concern by this time tomorrow. Some of the
midsouth...especially north Mississippi and west Tennessee has
already received 2-4 inches of rain. Additional heavy rain is
expected overnight...likely resulting in at least localized
flooding. If you live in a flood prone would be a good
idea to take action now to ensure your safety. Extended the Flash
Flood Watch through tomorrow evening for roughly the eastern half
of the midsouth.

Wednesday through the end of the work week...rain chances as well
as thunderstorms will remain enhanced...although with the lack of
upper level support...they should not be as organized. Expect
summertime type pulse storms driven mostly by daytime heating. Dew
points will remain in the middle to upper 60s...and precipitable waters will remain
around 1.5 inches so rain will be heavy where it falls.
Temperatures will trend warmer through Friday. Guidance has highs
by the end of the work week into the upper 80s. However...with
such a moist atmosphere...and rain expected...will undercut those
numbers slightly and keep readings in the middle 80s.

Don't see much chance in the pattern over the weekend.
Temperatures may turn slightly cooler as heights fall a bit...but
afternoon highs should remain in the low to middle 80s. Late
Sunday into early next week another trough will approach the
Mississippi River valley. Rainfall chances and the threat of
severe storms could increase once again.




00z taf cycle

Quiet early this evening. A few pop up rain showers/thunderstorms and rain showers but coverage
will be limited. South-southeast winds around 10 kts. A well organized squall
line will push across the area after midnight...followed by an
area of rain early Tuesday morning. Conds will deteriorate to
MVFR overnight. Rain will taper off and ceilings will gradually lift
to VFR on Tuesday. South winds at 12-15 kts with occasional higher
gusts on Tuesday.



Meg watches/warnings/advisories...
Arkansas...Flash Flood Watch through Tuesday afternoon for Clay-Craighead-
Crittenden-cross-Greene-Lawrence-Lee Arkansas-Mississippi-
Phillips-Poinsett-Randolph-St. Francis.

MO...Flash Flood Watch through Tuesday afternoon for Dunklin-Pemiscot.

MS...Flash Flood Watch through Tuesday afternoon for Coahoma-DeSoto-

Flash Flood Watch through Tuesday evening for Alcorn-Benton MS-
Calhoun-Chickasaw-Itawamba-Lafayette-Lee MS-Marshall-Monroe-

Tennessee...Flash Flood Watch through Tuesday afternoon for Dyer-Lake-

Flash Flood Watch through Tuesday evening for Benton Tennessee-Carroll-



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