[MCD] SWOMCD

Fri Apr 21 00:38:19 UTC 2006

ACUS11 KWNS 210035
SWOMCD
SPC MCD 210035 
ALZ000-MSZ000-ARZ000-LAZ000-210200-

MESOSCALE DISCUSSION 0591
NWS STORM PREDICTION CENTER NORMAN OK
0735 PM CDT THU APR 20 2006

AREAS AFFECTED...SERN AR...NRN MS

CONCERNING...SEVERE THUNDERSTORM WATCH 222...

VALID 210035Z - 210200Z

SVR TSTM THREAT APPEARS TO BE VERY LOW DURING THE REMAINING VALID
PORTIONS OF WW 222 THROUGH THE REST OF THE WATCH VALID TIME /02Z/.
WILL KEEP PORTIONS OF SERN AR/NRN MS IN THE WW 222 UNTIL THEN IN
CASE NEW DEVELOPMENT OCCURS. 

00Z JAN SOUNDING SHOWED AN INVERSION CENTERED AROUND 700 MB THAT IS
LIKELY PART OF THE REASON CONVECTION HAS FAILED TO BE SUSTAINED OVER
MUCH OF WW 222 THIS AFTERNOON/EARLY EVENING. WITH LIMITED
CONVERGENCE...WEAK LOW LEVEL WINDS /REF 00Z SHV AND JAN SOUNDINGS/
AND DECREASING INSTABILITY WITH NIGHTFALL...IT IS A VERY LOW
PROBABILITY THAT NEW SVR TSTM DEVELOPMENT WILL OCCUR BEFORE 02Z.
HOWEVER...SHORT TERM MODELS INDICATE THAT AS UPPER SYSTEM MOVES OUT
OF ERN TX...WAA WILL INCREASE. GIVEN RELATIVELY LIMITED CINH OVER
NRN LA /PER THE 00Z SHV SOUNDING/ NEW SVR TSTM DEVELOPMENT MAY
INCREASE LATER TONIGHT. HOWEVER THIS IS ANTICIPATED TO OCCUR WELL
AFTER 02Z...SO WW 222 WILL LIKELY BE ALLOWED TO EXPIRE.

..CROSBIE.. 04/21/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...BMX...MEG...JAN...LZK...

34908830 34229181 32969174 32898964 33158822 

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