Wednesday, September 12, 2007

DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 121545
SWODY1
SPC AC 121543

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1043 AM CDT WED SEP 12 2007

VALID 121630Z - 131200Z

..NO SVR TSTM AREAS FORECAST...

.SYNOPSIS...
PATTERN WILL REMAIN PROGRESSIVE ACROSS THE NRN TIER THIS PERIOD AS
SYSTEM THAT AFFECTED THE GRT LKS YESTERDAY CONTINUES NE TO LABRADOR
AND UPSTREAM DISTURBANCE NOW OVER THE CANADIAN RCKYS AMPLIFIES SE
INTO ND/MB. FARTHER S...VORT MAX NOW OVER SW CO AS NOTED ON W/V
IMAGERY...SHOULD EDGE SLOWLY SE INTO NRN NM LATER TODAY...AND INTO W
TX TONIGHT/EARLY THURSDAY.

AT LWR LVLS...SFC LOW ASSOCIATED WITH CANADIAN SYSTEM WILL
DEEPEN AS IT TRACKS E FROM THE NRN HIGH PLAINS INTO NRN MN/WRN
SWRN ONTARIO BY THURSDAY MORNING. STRONG COLD FRONT TRAILING SW
FROM LOW WILL SWEEP SE ACROSS THE NRN PLAINS. IN THE NWRN
GULF...TROPICAL DEPRESSION NINE EXPECTED TO MOVE SLOWLY NWD AND
STRENGTHEN SLIGHTLY BEFORE MOVING INLAND TONIGHT ON THE UPPER TX
COAST.

..SRN HI PLNS...
LEE TROUGH WILL STRENGTHEN OVER THE CNTRL/SRN HI PLNS TODAY IN
RESPONSE TO INCREASED WLY FLOW ON SRN EDGE OF AMPLIFYING CANADIAN
UPR IMPULSE. A DEEPLY-MIXED ENVIRONMENT WILL DEVELOP ALONG THE
TROUGH THIS AFTERNOON...WITH SBCAPE LIKELY INCREASING TO 500-1000
J/KG OVER ERN NM AND SE CO. SFC HEATING AND ASCENT ASSOCIATED WITH
CO UPR VORT SHOULD FOSTER TERRAIN-ENHANCED STORM DEVELOPMENT OVER
CNTRL NM BY MID AFTERNOON...WITH ISOLATED TO WIDELY SCTD STORMS
FORMING A BIT LATER ALONG LEE TROUGH.

BELT OF 20-25 KT WNWLY MID LVL FLOW ON SRN SIDE OF CO VORT WILL
ENHANCE DEEP SHEAR ACROSS REGION...BUT DEEP SHEAR LIKELY WILL REMAIN
SOMEWHAT MARGINAL FOR SUSTAINED/ORGANIZED STORMS.
NEVERTHELESS...GIVEN DEEPLY-MIXED BOUNDARY LYR...SIZABLE
TEMP-DEWPOINT SPREADS AND LIKELIHOOD FOR SOME CLUSTERING OF
ACTIVITY...A FEW OF THE STORMS COULD YIELD MARGINALLY SVR HAIL
AND/OR BRIEFLY SVR WIND GUSTS E INTO WRN PARTS OF THE OK/TX
PANHANDLE. ANY SUCH THREAT SHOULD QUICKLY DIMINISH AS THE LWR LVLS
COOL AFTER DARK.

..MIDDLE/UPR TX GULF CST...
APPROACH OF TD 9 WILL RESULT IN A GRADUAL INCREASE IN LOW LVL SPEED
AND DIRECTIONAL SHEAR ALONG THE MIDDLE AND UPR TX GULF CST THROUGH
EARLY THURSDAY. GIVEN VERY RICH MOIST ENVIRONMENT...SETUP COULD
BECOME INCREASINGLY FAVORABLE FOR DISCRETE OR SEMI-DISCRETE
SHOWERS/STORMS CONTAINING LOW LVL STORM ROTATION. WITH TROPICAL
SYSTEM NOT EXPECTED TO STRONGLY INTENSIFY...OVERALL WIND FIELD
SHOULD REMAIN WEAK AND ANY TORNADO THREAT POSED SHOULD REMAIN BRIEF
AND ISOLATED.

.HALES/BROYLES.. 09/12/2007

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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 chris@lib.siu.edu.

No comments: