SWODY1
SPC AC 260053
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0753 PM CDT FRI JUL 25 2008
VALID 260100Z - 261200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PARTS OF THE UPPER GREAT
LAKES AREA...
...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CNTRL HIGH PLAINS
AREA...
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE MID MS
VALLEY...
...CNTRL HIGH PLAINS...
STORMS CONTINUE DEVELOPING OVER THE HIGHER TERRAIN FROM WY SEWD
THROUGH NRN CO. ACTIVITY IS SPREADING EWD INTO AXIS OF STRONGER
INSTABILITY OVER THE CNTRL HIGH PLAINS OF WRN NEB AND NERN CO. WV
IMAGERY AND RUC ANALYSIS INDICATE A SHORTWAVE TROUGH CRESTING TOP OF
UPPER RIDGE MOVING INTO WY. THIS FEATURE MAY CONTINUE TO AID
DEVELOPMENT OVER THE HIGHER TERRAIN AND STORMS WILL SPREAD EWD INTO
THE HIGH PLAINS WHERE A MODEST LOW LEVEL JET IS FORECAST TO DEVELOP.
FARTHER EAST OVER THE PLAINS...CONVECTIVE INHIBITION WILL INCREASE
THIS EVENING AS THE BOUNDARY LAYER BEGINS TO COOL...AND SUGGESTS
STORMS WILL PROBABLY HAVE AN INCREASINGLY DIFFICULT TIME REMAINING
ORGANIZED WITH EWD EXTENT INTO CNTRL NEB. SELY LOW LEVEL FLOW
VEERING TO WLY 25-30 KT AT 500 MB IS RESULTING IN SUFFICIENT BULK
SHEAR FOR ORGANIZED STORM STRUCTURES. ISOLATED LARGE HAIL AND
DAMAGING WIND WILL REMAIN THE PRIMARY THREATS NEXT FEW HOURS.
...MID MS VALLEY REGION...
A WARM FRONT EXTENDS FROM A WEAK SURFACE LOW IN W CNTRL MO SEWD
THROUGH SERN MO. THE ATMOSPHERE REMAINS QUITE UNSTABLE ALONG AND
SOUTH OF THIS BOUNDARY WITH MLCAPE FROM 2000 TO 3000 J/KG. THIS
REGION IS ON SRN FRINGE OF STRONGER UPPER FLOW. NWLY BULK SHEAR OF
30-35 KT IS SUPPORTIVE OF MAINLY MULTICELL STORMS AND MARGINALLY
FAVORABLE FOR SOME STORMS TO DEVELOP MID-LEVEL ROTATION. STORMS WILL
LIKELY CONTINUE DEVELOPING THROUGH LATE EVENING...ORGANIZING INTO
SMALL CLUSTERS AS THEY SPREAD SEWD. THE STRONGER STORMS WILL REMAIN
CAPABLE OF PRODUCING ISOLATED STRONG DOWNBURSTS AND HAIL NEXT FEW
HOURS...THOUGH OVERALL HAIL THREAT SHOULD REMAIN LIMITED BY WARM MID
LEVEL TEMPERATURES.
...GREAT LAKES AREA...
NARROW AXIS OF MODEST INSTABILITY PERSISTS IN WARM SECTOR FROM NERN
IA...SERN MN THROUGH WI WITH MLCAPE FROM 1000 TO 1500 J/KG. FORCING
FOR ASCENT WITH DPVA ATTENDING SHORTWAVE TROUGH MOVING EWD THROUGH
NRN MN AND NRN WI CONTINUES TO PROMOTE WIDELY SCATTERED STORMS OVER
WARM SECTOR. LOW LEVEL FLOW HAS VEERED TO WSWLY AHEAD OF FRONT DUE
TO CIRCULATION AROUND PRIMARY UPPER LOW IN ONTARIO. THIS IS LIMITING
CONVERGENCE ALONG THE FRONT AN OVERALL MAGNITUDE OF VERTICAL SHEAR.
HOWEVER...AN UPPER JET ROTATING AROUND BASE OF SHORTWAVE TROUGH IS
MAINTAINING AROUND 35 KT UNIDIRECTIONAL BULK SHEAR...SUFFICIENT FOR
SOME UPDRAFTS TO DEVELOP MID LEVEL ROTATION. THIS ENVIRONMENT WILL
PROMOTE A THREAT OF ISOLATED DAMAGING WIND AND HAIL NEXT COUPLE
HOURS...BUT THREAT SHOULD BEGIN TO WANE WITH ONSET OF NOCTURNAL
COOLING.
...SRN AZ AND SERN CA...
ELY FLOW IN THE 700-500 MB LAYER WILL CONTRIBUTE TO STORMS
DEVELOPING OVER THE HIGHER TERRAIN SPREADING WSWWD THROUGH THE
DESERT VALLEYS WHERE LARGE BOUNDARY LAYER TEMPERATURE DEWPOINT
SPREADS...AND MODERATE INSTABILITY WILL SUPPORT A THREAT FOR
ISOLATED DAMAGING WIND GUSTS THROUGH LATE EVENING.
..DIAL.. 07/26/2008
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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