MESO: Mesoscale Discussion 2200

ACUS11 KWNS 050519
SWOMCD
SPC MCD 050518
NCZ000-TNZ000-GAZ000-ALZ000-MSZ000-LAZ000-051115-

MESOSCALE DISCUSSION 2200
NWS STORM PREDICTION CENTER NORMAN OK
1118 PM CST FRI DEC 04 2009

AREAS AFFECTED...ERN MS...CENTRAL AND NRN AL...FAR NRN GA...ERN TN
AND FAR WRN NC

CONCERNING...HEAVY SNOW

VALID 050518Z - 051115Z

AN EARLY SEASON SNOWFALL EVENT WILL SHIFT OUT OF MS GENERALLY BY 09Z
AND TRANSLATE NEWD ACROSS CENTRAL/NRN AL AND FAR NRN GA INTO THE
MOUNTAINS OF TN/NC BY 09-12Z. HOURLY SNOWFALL RATES ARE EXPECTED TO
REMAIN LIGHT...THOUGH VISIBILITIES MAY BE REDUCED TO ONE MILE AT
TIMES.

PRECIPITATION ONGOING ACROSS MS/SERN LA IS FORECAST TO CONTINUE
SPREADING NEWD INTO AL THROUGH 09Z WITHIN A ZONE OF ASCENT OCCURRING
AHEAD OF A PROGRESSIVE S/W TROUGH. SURFACE OBSERVATIONS INDICATE A
RAPID CHANGE OVER FROM RAIN TO SNOW /WITH A MIXTURE OF SLEET IN SERN
LA/ HAS BEEN OCCURRING AS WET BULB COOLING DROPS TEMPERATURES TO
AROUND 32-35 DEG F. WITH SURFACE DEWPOINTS GENERALLY RESIDING IN THE
TWENTIES DOWNSTREAM FROM THE ONGOING PRECIPITATION
SHIELD...ADDITIONAL WET BULB COOLING TO NEAR FREEZING IS LIKELY AS
RAIN OVERSPREADS AL/NRN GA/ERN TN/WRN NC...WHICH WILL CONTINUE TO
SUPPORT A TRANSITION TO SNOW. HOWEVER...MODEL FORECAST GUIDANCE
INDICATES STRONGEST ASCENT WILL SHIFT AWAY FROM THE REGION DURING
THE OVERNIGHT...WHICH SUGGESTS THAT HOURLY SNOWFALL RATES WILL BE
LIGHT /GENERALLY UNDER A HALF INCH PER HR/.

..GARNER.. 12/05/2009

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

...NOTICE...
SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A
SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR
TIMES A DAY...AROUND 00 UTC...06 UTC...12 UTC...AND 18 UTC
FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS.

ATTN...WFO...GSP...MRX...FFC...OHX...BMX...HUN...MOB...JAN...
LIX...

LAT...LON 35038320 32828522 31128841 30718985 31019043 31819024
35028654 36338469 36578397 36398315 35888286 35038320

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.