SWODY1
SPC AC 190426
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1126 PM CDT SUN SEP 18 2011
VALID 191200Z - 201200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
AN UPPER TROUGH AXIS ACROSS THE MS RIVER VALLEY WILL WEAKEN AS IT
EJECTS NEWD ACROSS THE OH VALLEY AND INTO THE NERN STATES BY TUE. AT
THE SURFACE...A WEAK TROUGH AND COLD FRONT WILL STRETCH FROM LOWER
MI SWWD INTO SE TX AT 00Z...WITH MID TO UPPER 60S BOUNDARY LAYER
DEWPOINTS AHEAD OF IT.
TO THE W...AN UPPER WAVE IS FORECAST TO AMPLIFY ACROSS MT DURING THE
AFTERNOON...SPREADING INTO THE NRN PLAINS OVERNIGHT. A DEVELOPING
COLD FRONT AS WELL AS A DEEPENING SURFACE LOW WILL BOTH MAXIMIZE
FORCING FOR ASCENT ACROSS THIS REGION...BUT MOISTURE WILL BE LIMITED
FOR STORMS.
...ERN MT INTO THE DAKOTAS...
CONVERGENCE WILL INCREASE MARKEDLY DURING THE AFTERNOON ACROSS ERN
MT AS A COLD FRONT DEVELOPS. MODESTLY STEEP LOW TO MID LEVEL LAPSE
RATES WILL EXIST AHEAD OF THE FRONT DUE TO HEATING...BUT MOISTURE
WILL BE MEAGER WITH MUCAPE OF 100-200 J/KG EXPECTED. HOWEVER...GIVEN
VERY STRONG WIND FIELDS AND BOUNDARY LAYER MIXING...A FEW
CONVECTIVELY ENHANCED WIND GUSTS WILL BE POSSIBLE. THE THREAT OF
HIGH BASED/STRONGLY FORCED SEVERE WIND GUSTS MAY PERSIST INTO THE
EVENING ACROSS NWRN SD AND INTO ND AS BOUNDARY LAYER LAPSE RATES
REMAIN STEEP DUE TO MIXING...AND FORCING INCREASES FURTHER NEAR THE
SURFACE LOW/FRONT.
...LOWER OH/MS VALLEY SWWD INTO SERN TX...
RAIN AND STORMS WILL BE ONGOING MON MORNING OVER A LARGE AREA
STRETCHING FROM ERN TX/LA INTO NEWD TO LOWER MI NEAR A WEAK SURFACE
TROUGH. AS THE UPPER TROUGH DEPARTS AND WEAKENS...WIND FIELDS WILL
SLACKEN ACROSS THE REGION...AND GIVEN WIDESPREAD PRECIP AND
CLOUDS...SUBSTANTIAL DESTABILIZATION IS NOT EXPECTED.
THIS...COMBINED WITH WEAK SHEAR...SHOULD PRECLUDE MUCH OF A SEVERE
THREAT.
..JEWELL/ROGERS.. 09/19/2011
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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:
Post a Comment