Saturday, September 12, 2009

DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 121606
SWODY1
SPC AC 121602

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1102 AM CDT SAT SEP 12 2009

VALID 121630Z - 131200Z

...NO SVR TSTM AREAS FORECAST...

BLOCKED FLOW PATTERN IN PLACE ACROSS CONUS. UPPER LOW CONTINUES TO
GRADUALLY DEVELOP OVER TX AS 70KT SUB-TROPICAL JET APPROACHES FROM
NRN MEXICO PROVIDING INCREASING UPPER DIVERGENCE ACROSS SRN HALF OF
TX. ALSO IN RESPONSE TO DEVELOPMENTS ALOFT...A SURFACE LOW HAS NOW
FORMED OFFSHORE ABOUT 50 MILES E OF CRP.

WHILE CONDITIONS ARE NOT FAVORABLE FOR SIGNIFICANT DEEPENING OF THE
SURFACE LOW...SHEAR PROFILES WILL GRADUALLY INCREASE THRU THE
FORECAST PERIOD FROM THE UPPER TX COAST EWD TO SRN MS AS LOW SLOWLY
MOVES ENEWD JUST OFFSHORE TO SRN LA BY 12Z SUN.

WITH A CONTINUED FEED OF VERY MOIST/TROPICAL AIR MASS INTO LWR MS
VALLEY...CONDITIONS WILL BE FAVORABLE FOR EXTENSIVE PCPN INCLUDING
THUNDERSTORMS...PARTICULARLY THIS EVENING/OVERNIGHT WITH INCREASE OF
THE LARGE SCALE ASCENT. LOW LEVEL VEERING SHEAR PROFILES WILL
SUPPORT POTENTIAL FOR ROTATING STORMS...PROVIDED SUFFICIENT
INSTABILITY IS AVAILABLE. WITH LAPSE RATES GENERALLY LESS THAN 6C/KM
AND A SATURATED COLUMN...WILL JUST MAINTAIN A LOW THREAT FOR
ISOLATED TORNADOES AND GUSTY WINDS IN STRONGER
CONVECTION...PRIMARILY TONIGHT...MID GULF COASTAL REGION.

..HALES/GRAMS.. 09/12/2009

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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: