National Weather Service United States Department of Commerce

Fresh Snow and Temperature Outlook Ahead of Christmas Day

If you are looking for fresh snow by Christmas morning or are curious about potential travel disruptions, the best chances for at least 1" of new snowfall early this week exist across the mountainous West, Great Lakes, and Northeast. Otherwise, temperatures this last full week of December will average above normal for much of the lower 48 states. Read More >

Mesoscale Discussion #0432 issued at 1929 UTC 10 April 2009
MESOSCALE DISCUSSION 0432
NWS STORM PREDICTION CENTER NORMAN OK
0229 PM CDT FRI APR 10 2009
   
AREAS AFFECTED...NRN AND CNTRL GA
   
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
VALID 101929Z - 102100Z
   
STORMS ARE EXPECTED TO DEVELOP EWD INTO NRN AND CNTRL GA LATER THIS
AFTERNOON AND EVENING. THREAT WILL EXIST FOR SUPERCELLS CAPABLE OF
PRODUCING LARGE HAIL AND TORNADOES...A FEW OF WHICH COULD BE STRONG.
DAMAGING WIND WILL ALSO BE POSSIBLE WITH SOME OF THE STORMS. A WW
WILL LIKELY BE NEEDED BY 20-21Z.
   
PRE-FRONTAL LINE OF MOSTLY DISCRETE SUPERCELLS EXTENDS FROM MIDDLE
TN SSWWD THROUGH NRN AL MOVING EAST AT 40-45 KT. A CONVECTIVELY
ENHANCED BOUNDARY EXTENDS FROM NRN SC THROUGH NE GA INTO ERN TN.
SOUTH OF THESE FEATURES...OTHER PRE-FRONTAL CONVERGENCE BOUNDARIES
MANIFESTED BY CLOUD STREETS EXIST OVER MUCH OF THE WARM SECTOR
ACROSS CNTRL AL EXTENDING INTO WRN GA. LATEST OBJECTIVE ANALYSIS AND
THE 18Z RAOB FROM BIRMINGHAM AND ATLANTA INDICATES MINIMAL TO NO CAP
IN WARM SECTOR. THEREFORE...DESPITE A TENDENCY FOR THE STRONGER DEEP
FORCING ASSOCIATED WITH THE EWD ADVANCING SHORTWAVE TROUGH TO REMAIN
FARTHER NORTH OVER THE TN VALLEY...CONVECTIVE INITIATION MAY OCCUR
AS FAR SOUTH AS NORTH CNTRL GA AS THE BOUNDARY LAYER DESTABILIZES
EWD WITH TIME. THE COUPLED LOW-MID LEVEL JET STRUCTURE ATTENDING THE
SHORTWAVE TROUGH WILL MAINTAIN FAVORABLE WIND PROFILES WITH BULK
SHEAR 50+ KT AND 0-1 KM STORM RELATIVE HELICITY FROM 200-300 M2/S2
INTO THE EARLY EVENING. THIS ENVIRONMENT WILL SUPPORT ORGANIZED
STORMS INCLUDING SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND
TORNADOES.
   
..DIAL.. 04/10/2009
   
   
ATTN...WFO...GSP...FFC...BMX...
   
LAT...LON   34948457 34638398 34378351 34148286 33278350 32848474
            33498564 34758503 34948457