Saturday, July 12, 2008

DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 130046
SWODY1
SPC AC 130044

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0744 PM CDT SAT JUL 12 2008

VALID 130100Z - 131200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE OH
VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF OK AND NWRN
AR...

...OH VALLEY...

NE-SW ORIENTED MCS HAS EVOLVED OVER THE LOWER OH VALLEY
REGION...EXTENDING ROUGHLY FROM MIE IN NERN IND TO NEAR MDH IN SRN
IL. A SIGNIFICANT COLD POOL HAS DEVELOPED WITH THIS ACTIVITY AS
PRECIPITATION TRAILS LEADING WIND SHIFT BY AT LEAST 50 MI. GIVEN
THE MODEST SWLY FLOW ALOFT WITHIN THE BASE OF THE TROUGH IT APPEARS
THIS MCS WILL PROGRESS ACROSS THE REMAINDER OF SRN IND INTO WRN OH
WHERE WEAKENING IS EXPECTED...MAINLY DUE TO THE LOSS OF DAYTIME
HEATING. PRIOR TO WEAKENING LOCALLY STRONG OR PERHAPS ISOLATED
DAMAGING WINDS MAY ACCOMPANY LEADING EDGE OF MCS.

...OK/AR...

VERY WARM TEMPERATURES DEVELOPED ACROSS MUCH OF SWRN OK THIS
AFTERNOON WHERE READINGS SOARED LOCALLY ABOVE 100F. THIS PROVED
INSTRUMENTAL IN STEEPENING LAPSE RATES AND CREATING A FAVORABLE
ENVIRONMENT FOR ENHANCED DOWNDRAFTS. STRONG THUNDERSTORMS DEVELOPED
ALONG SW-NE ORIENTED COLD FRONT AND QUICKLY PRODUCED DAMAGING WIND
GUSTS. RECENTLY A WIND GUST TO 62 KT WAS OBSERVED AT LTS IN THE
WAKE OF EARLIER CONVECTION. BOUNDARY LAYER COOLING SHOULD RESULT IN
WEAKENING UPDRAFTS/DOWNDRAFTS...THOUGH STORM MERGERS MAY ENHANCE
LOCAL WIND THREAT. AS THE EVENING PROGRESSES IT APPEARS
THUNDERSTORMS WILL BECOME MORE CONCENTRATED FROM NCNTRL OK INTO
NWRN/WCNTRL AR. A GRADUALLY EXPANDING MCS IS UNDERWAY NORTH OF
I-40. 00Z SOUNDING FROM OUN EXHIBITS MORE THAN ADEQUATE
BUOYANCY...MLCAPE ON THE ORDER OF 1700 J/KG...WITH SUFFICIENT SHEAR
FOR SEWD-PROPAGATING CLUSTERS. GIVEN THE LOOSE ORGANIZATION ALREADY
ACROSS THIS REGION IT APPEARS A SLOW-MOVING MCS SHOULD SPREAD ACROSS
MUCH OF NERN OK INTO WCNTRL AR BY 06Z.

...SWRN U.S...

LATEST DIAGNOSTIC DATA SUGGESTS PRECIPITABLE WATER VALUES REMAIN
QUITE HIGH ACROSS SRN CA...VALUES IN EXCESS OF 1.5 INCHES. WITH
STRONG HEATING NOTED ACROSS THIS REGION THUNDERSTORMS EASILY
DEVELOPED BENEATH WWD MIGRATING UPPER VORT...LOCATED OVER SAN
BERNARDINO COUNTY. GIVEN THE RELATIVELY HIGH CLOUD BASES AND 40-45
SFC TEMP/DEW POINT SPREADS...STRONG RAIN CORES MAY ENHANCE LOCALLY
DAMAGING WIND POTENTIAL. DIURNAL COOLING WILL GREATLY REDUCE THIS
POTENTIAL.

..DARROW.. 07/13/2008

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