SWODY1
SPC AC 230557
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1257 AM CDT MON APR 23 2007
VALID 231200Z - 241200Z
..THERE IS A MDT RISK OF SVR TSTMS LATER THIS AFTERNOON AND TONIGHT
ACROSS E CENTRAL CO...W CENTRAL AND SWRN KS...THE OK/TX PANHANDLE
AND A SMALL PART OF NWRN OK....
..THERE IS A SLGT RISK OF SVR TSTMS SURROUNDS THE MDT RISK ACROSS
PARTS OF THE CENTRAL AND SRN HIGH PLAINS....
..SIGNIFICANT SEVERE WEATHER EVENT IS EXPECTED ACROSS PARTS OF THE
CENTRAL AND SOUTHERN HIGH PLAINS LATE THIS AFTERNOON AND TONIGHT...
..SYNOPSIS...
MID/UPPER LEVEL LOW DEEPENING OVER W CENTRAL/SRN NV THIS MORNING IS
FORECAST TO MOVE EWD OVER THE FOUR CORNERS AREA AND INTO CENTRAL/SRN
COLORADO BY THE END OF THE PERIOD. MODELS ARE DIFFERENT IN HANDLING
OF SURFACE FEATURES WITH THE NAM BEING THE MOST AGGRESSIVE IN
BRINGING A DRYLINE/SURFACE TROUGH EWD INTO THE NERN TX PANHANDLE/WRN
OK BY 24/00Z. HOWEVER...THE UKMET AND GFS MODELS ARE ALL SLOWER
PLACING THIS FEATURE FROM A LOW BETWEEN PUB AND DEN THEN SEWD/SWD
THROUGH THE CENTRAL PARTS OF THE OK/TX PANHANDLE WHICH IS THE
PREFERRED LOCATION AT THIS TIME.
..E CENTRAL CO AND WRN KS INTO PARTS OF THE OK/TX PANHANDLE/NWRN
OK...
LOW LEVEL JET IS EXPECTED TO INCREASE THIS AFTERNOON AS BROAD
CYCLONIC CIRCULATION ASSOCIATED WITH MID/UPPER LEVEL TROUGH MOVING
EWD ACROSS THE SOUTHERN INTERMOUNTAIN REGION. THIS JET WILL
INCREASE FROM 30-35 KT THIS AFTERNOON EXTENDING FROM NWRN PARTS OF
TX NWD/NWWD INTO NWRN KS. A WARM FRONTAL BOUNDARY IS EXPECTED TO
MOVE NWD FROM NRN OK THIS MORNING INTO E CENTRAL CO EXTENDING SEWD
INTO SERN KS BY TONIGHT. LOW LEVEL THERMAL AND MOISTURE ADVECTION
IS EXPECTED IN THE VICINITY OF THE LOW LEVEL JET/FRONTAL BOUNDARY BY
THIS EVENING AS EXIT REGION OF 50-70 KT SWLY MID LEVEL JET EXTENDS
OVER THE BOUNDARY ENHANCING VERTICAL SHEAR PROFILES ACROSS PARTS OF
ERN CO INTO SWRN KS AND THE OK AND NRN TX PANHANDLES.
AIR MASS WILL BECOME MODERATELY UNSTABLE DURING THE DAY AS FORECAST
SURFACE TEMPERATURES ARE EXPECTED TO BE INTO THE LOW/MID 70S ALONG
THE CO/KS BORDER GIVING MLCAPE VALUES BETWEEN 2000 AND 2300 J/KG.
THIS COMBINED WITH DEEP LAYER SHEAR VALUES BETWEEN 50-60 KT CREATES
VERY FAVORABLE ENVIRONMENT TO SUPPORT STRONG UPDRAFTS/DISCRETE
SUPERCELLS IN THE VICINITY/JUST OFF THE DRYLINE BY LATE AFTERNOON.
GIVEN THAT LOW/MID LEVEL LAPSE RATES ARE BETWEEN 7.0 AND 8.0C/KM BY
LATE AFTERNOON...LARGE HAIL MAY BE THE INITIAL THREAT WHEN THE
STORMS DEVELOP. BY 24/00Z...FORECAST SOUNDINGS SHOW EXIT REGION OF
MID/UPPER LEVEL JET COUPLING WITH SSELY LOW LEVEL FLOW TO ENHANCE
THE LOW/MID LEVEL SHEAR PROFILE INCREASING 0-3KM HELICITY TO AROUND
325 M2/S2 AND 0-1 KM HELICITY TO NEAR 150 M2/S2 SUFFICIENT
MESOCYCLONE/TORNADO DEVELOPMENT NEAR THE CO/KS BORDER INTO SWRN KS.
THERE ARE INDICATIONS THAT A FEW DAMAGING TORNADOES COULD OCCUR WITH
THESE STORMS GIVEN THE SUFFICIENT 0-1KM SHEAR AND LCL/LFC HEIGHTS
BETWEEN 1000 AND 1500 M.
..LOWER OHIO VALLEY NEWD INTO PARTS OF THE LOWER GREAT LAKES...
COLD FRONTAL BOUNDARY WILL MOVE SLOWLY SEWD TODAY AND TONIGHT
EXTENDING FROM CENTRAL LAKE ERIE SWWD THROUGH CENTRAL INDIANA AND
SRN MO. SCATTERED THUNDERSTORMS ARE EXPECTED ALONG THE FRONTAL
BOUNDARY THIS AFTERNOON AND EARLY TONIGHT AS AIR MASS JUST AHEAD OF
THE BOUNDARY WILL BECOME UNSTABLE WITH MLCAPE BETWEEN 500 AND 1000
J/KG. SOME OF THIS ACTIVITY COULD PRODUCE SOME STRONG GUSTY WINDS
GIVEN DRY AIR AT MID LEVELS AND THE PRESENCE OF 30-40 KT OF DEEP
LAYER SHEAR. GIVEN THE LIMITED INSTABILITY IS REASON FOR LIMITING
SEVERE POTENTIAL WITH THIS ACTIVITY.
.MCCARTHY/JEWELL.. 04/23/2007
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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:
Post a Comment