DAY2SVR: Nws Storm Prediction Center Norman Ok

ACUS02 KWNS 060528
SWODY2
SPC AC 060527

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1227 AM CDT SAT OCT 06 2007

VALID 071200Z - 081200Z

..NO SVR TSTM AREAS FORECAST...

..SYNOPSIS...

UPPER TROUGH OVER THE WRN U.S. WILL ADVANCE INTO THE PLAINS SUNDAY.
HOWEVER...MODELS CONTINUE TO DIFFER REGARDING DETAILS OF THE
EVOLUTION OF THIS FEATURE. THE GFS AND NAM HAVE TRENDED MORE TOWARD
YESTERDAYS RUN OF THE ECMWF BY ADVANCING THE UPPER TROUGH INTO THE
PLAINS AS A POSITIVE TO NEUTRAL TILT SYSTEM. THESE MODELS ARE NOW
PLACING MORE EMPHASIS ON VORT MAX FORECAST TO LIFT INTO NRN PORTION
OF UPPER TROUGH...AND VORT MAX FORECAST TO ROTATE INTO BASE OF UPPER
TROUGH NOW APPEARS SLOWER AND WEAKER THAN YESTERDAYS RUNS. THUS THE
LOW LEVEL RESPONSE TO THE MASS FIELDS IS MUCH WEAKER OVER THE CNTRL
AND SRN PLAINS WITH LIMITED CYCLOGENESIS AND A MUCH WEAKER LOW LEVEL
JET FORECAST. THESE FACTORS LOWER CONFIDENCE IN OVERALL SEVERE
POTENTIAL THIS PERIOD.

..PORTIONS OF THE SRN AND CNTRL PLAINS UPPER MS VALLEY AND GREAT
LAKES REGIONS...

COLD FRONT INITIALLY FROM THE UPPER MS VALLEY SWWD INTO THE SRN HIGH
PLAINS EARLY SUNDAY WILL ADVANCE SLOWLY SEWD DURING THE DAY AS CP
HIGH PRESSURE BUILDS OVER THE WRN AND CNTRL STATES. PRE-FRONTAL WARM
SECTOR WILL BE CHARACTERIZED BY LOW LEVEL DEWPOINTS GENERALLY IN THE
UPPER 60S. HOWEVER...WEAK LAPSE RATES AND POTENTIAL FOR AREAS OF
WIDESPREAD CLOUDS WILL LIMIT MLCAPE TO 1000-1500 J/KG. WITH THE
UPPER TROUGH NOW EXPECTED TO MAINTAIN MORE OF A POSITIVE TO NEUTRAL
TILT...MOST OF THE STRONGER FORCING FOR ASCENT WILL LIKELY REMAIN IN
THE POST FRONTAL ZONE WITH LITTLE IN THE WAY OF CYCLOGENESIS AND
LIMITED RESPONSE OF THE LOW LEVEL WINDS. THUS LOW LEVEL WIND FIELDS
AND DEEP VERTICAL SHEAR IN WARM SECTOR ARE EXPECTED TO REMAIN MOSTLY
SUPPORTIVE OF MULTICELL STORMS. STORMS MAY INCREASE IN INTENSITY
ALONG AND JUST AHEAD OF THE FRONT DURING THE AFTERNOON AS THE
ATMOSPHERE UNDERGOES MODEST DESTABILIZATION WITH A THREAT FOR MAINLY
ISOLATED STRONG WIND GUSTS AND MARGINALLY SEVERE HAIL. HOWEVER...AT
THIS TIME EXPECTED KINEMATIC AND THERMODYNAMIC ENVIRONMENTS DO NOT
APPEAR SUFFICIENTLY ROBUST TO WARRANT A CATEGORICAL OUTLOOK.

.DIAL.. 10/06/2007

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