[MCD] SWOMCD

Thu Apr 20 18:41:21 UTC 2006

ACUS11 KWNS 201839
SWOMCD
SPC MCD 201838 
TNZ000-GAZ000-ALZ000-MSZ000-LAZ000-ARZ000-202045-

MESOSCALE DISCUSSION 0583
NWS STORM PREDICTION CENTER NORMAN OK
0138 PM CDT THU APR 20 2006

AREAS AFFECTED...NRN AL...SRN MIDDLE TN...NRN/CENTRAL MS

CONCERNING...SEVERE THUNDERSTORM WATCH 221...

VALID 201838Z - 202045Z

CONTINUE ALL OF WW 221.

WEAK SURFACE CONVERGENCE COMBINED WITH MID/HIGH CLOUD COVER ARE
LIKELY THE MAIN INHIBITING FACTORS FOR NEW DEEP CONVECTIVE
DEVELOPMENT OVER NRN AL/SRN MIDDLE TN. HOWEVER...A FEW MORE HRS OF
HEATING AND LIKELY CLEARING OF SOME OF THE CLOUD COVER SHOULD AID IN
A GREATER POTENTIAL FOR SVR TSTM DEVELOPMENT OVER WW 221 BY
MID-AFTERNOON.

FURTHER WEST...A WELL DEFINED MCV ON SAT IMAGERY OVER THE ARKLATEX
WAS MOVING QUICKLY NEWD. AHEAD OF THIS FEATURE...AN OUTFLOW BOUNDARY
WAS WELL DEFINED EXTENDING FROM SERN AR ENEWD INTO NRN MS. OBJECTIVE
ANALYSIS INDICATES THAT THE AIRMASS OVER MUCH OF NRN/CENTRAL MS HAS
LITTLE REMAINING CINH. WITH THE FOCUSED CONVERGENCE ALONG THE
BOUNDARY AND APPROACHING UPPER SUPPORT...SCT CONVECTION MAY DEVELOP
OVER NRN/CENTRAL MS IN THE NEXT FEW HRS. MODERATE INSTABILITY AND
SHEAR IN PLACE OVER THE AREA WOULD SUPPORT A SVR THREAT WITH ANY
TSTMS. THUS...A NEW WW MAY BE NEEDED WEST OF WW 221 IN THE NEXT HOUR
OR SO.

..CROSBIE.. 04/20/2006

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

ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG...JAN...

35068784 35648756 35598481 34458526 33068577 32918872
32929108 33459119 34499034 

WWWW