Tuesday, January 6, 2009

DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 070101
SWODY1
SPC AC 070058

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0658 PM CST TUE JAN 06 2009

VALID 070100Z - 071200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM A PORTION OF THE CENTRAL
GULF COAST STATES TO WRN CAROLINAS...

...SYNOPSIS...
FULL LATITUDE TROUGH OVER THE CENTRAL U.S. EARLY THIS EVENING WILL
PROGRESS EWD TO THE MS RIVER VALLEY BY 12Z WEDNESDAY. A COUPLE OF
SHORT WAVE TROUGHS EMBEDDED WITHIN THE SRN EXTENT OF THE LARGE SCALE
TROUGH...FROM OZARKS TO SRN PLAINS...WILL MOVE EWD OVERNIGHT AND
REACH THE OH TO LOWER MS VALLEYS BY THE END OF THE FORECAST PERIOD.
IN THE LOW LEVELS...LOW PRESSURE WILL TRACK EWD THROUGH THE OH
VALLEY...WHILE ANOTHER WEAKER LOW...CURRENTLY LOCATED OVER FAR NRN
GA...WILL MOVE INTO WRN CAROLINAS OVERNIGHT. AT 12Z WEDNESDAY...A
SURFACE FRONT SHOULD EXTEND FROM THE UPPER OH VALLEY SSWWD THROUGH
THE WRN CAROLINAS INTO WRN GA TO THE CENTRAL GULF.

...NRN GA/WRN CAROLINAS...
THE PORTION OF THE FRONT EXTENDING SWD FROM THE SRN APPALACHIANS TO
THE GULF COAST WILL REMAIN THE AREA OF CONCERN THIS FORECAST PERIOD.
HOWEVER...GIVEN WEAK INSTABILITY...ESPECIALLY FROM NRN GA INTO WRN
CAROLINAS...AND THE CONTINUED PRESENCE OF A MID LEVEL INVERSION PER
00Z FFC SOUNDING SUGGEST UPDRAFTS WILL CONTINUE TO STRUGGLE. THIS
TREND IS INDICATED BY RECENT LOSS OF LIGHTNING PRODUCTION WITH ALL
ACTIVITY PROGRESSING ENEWD ALONG THE EXTENT OF THE SURFACE FRONT.
STRONG SHEAR SUGGESTS A NON-ZERO THREAT FOR AN ISOLATED TORNADO OR
DAMAGING WINDS WITH ANY SUSTAINED ACTIVITY...BUT SEVERE WEATHER
THREAT SHOULD DIMINISH OVER THIS AREA.

...CENTRAL GULF COAST STATES...
MODELS INDICATE SOME POTENTIAL FOR REDEVELOPMENT/INTENSIFICATION
ALONG THE SRN EXTENT OF THE SURFACE FRONT FROM FAR SERN MS AND EWD
AS THE FRONT PROGRESSES THROUGH SRN AL/FL PANHANDLE TO WRN GA
OVERNIGHT. STRONGER HEIGHT FALLS /90-120 METERS/ ARE EXPECTED TO
SPREAD EWD ACROSS THE GULF COAST STATES THIS PERIOD RESULTING IN AN
INCREASE IN DEEP LAYER FORCING ALONG THE FRONT. THIS WOULD
EFFECTIVELY WEAKEN THE PRE-FRONTAL MID LEVEL INVERSION AND SUPPORT
UPDRAFTS DEEP ENOUGH FOR LIGHTNING PRODUCTION ALONG AND AHEAD OF THE
BOUNDARY. MUCAPE 500-1000 J/KG OVER SRN AL/FL PANHANDLE COMBINED
WITH STRONG DEEP LAYER /60 KT/ AND LOW LEVEL SHEAR SUGGEST A THREAT
FOR DAMAGING WINDS AND ISOLATED TORNADOES...GIVEN THE REDEVELOPMENT
OF STORMS. MODELS ARE ALSO INDICATING THE DEVELOPMENT OF A REAR
INFLOW JET OVER SERN AL/FL PANHANDLE BETWEEN 09-12Z WHICH WOULD
INCREASE THE THREAT FOR DAMAGING WINDS.

..PETERS.. 01/07/2009

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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.

No comments: