SPC AC 151239
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0739 AM CDT WED APR 15 2009
VALID 151300Z - 161200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
DEEP NV UPR LOW EXPECTED MOVE SLOWLY ESE TOWARD THE FOUR CORNERS
THIS PERIOD AS DOWNSTREAM RIDGE PROGRESSES E FROM THE PLNS TO THE MS
VLY. AT LWR LVLS...LEE LOW SHOULD STRENGTHEN OVER ERN CO LATER
TODAY/TONIGHT WHILE A N-S LEE TROUGH SHARPENS OVER THE CNTRL/SRN HI
PLNS. THE TROUGH WILL SERVE AS A FOCUS FOR ISOLD DIURNAL STORMS.
...TX PANHANDLE/TX S PLNS...
A NARROW AXIS OF MODEST /PW AROUND .75 INCHES/ MOISTURE RETURN WILL
SPREAD N ACROSS W TX TODAY AS SSELY LOW LVL FLOW INCREASES OVER THE
HI PLNS AHEAD OF NV UPR LOW. DEWPOINTS SHOULD REACH THE 40S F OVER
TX E OF LEE TROUGH. COMBINED WITH DAYTIME HEATING AND EML
ALOFT...EXPECT AFTN SBCAPE OF 250-500 J/KG. WIND PROFILES WILL BE
FAVORABLE FOR SUSTAINED STORMS/SUPERCELLS...WITH 20-25 KT NEAR-SFC
SSE FLOW VEERING TO 40 KT WSWLYS AT 500 MB.
PRESENCE OF EML CAP AND ABSENCE OF UPR LVL FORCING FOR ASCENT LIKELY
WILL STRONGLY LIMIT POTENTIAL FOR DEEP MOIST CONVECTION.
NEVERTHELESS...ANY STORMS THAT DO FORM IN RESPONSE TO HEATING AND
LOW-LEVEL CONVERGENCE ALONG LEE TROUGH COULD BECOME BRIEFLY
VIGOROUS/SVR. ALONG WITH A THREAT FOR HAIL...GUSTY WINDS ALSO WOULD
BE POSSIBLE GIVEN DEEP/RELATIVELY DRY SUB-CLOUD LYR. ANY SUCH
THREAT APPEARS MOST PROBABLE VERY LATE IN THE DAY...AND SHOULD
DIMINISH THROUGH THE EVENING.
LATE IN THE PERIOD...I.E. AFTER ABOUT 09Z THU...RENEWED STORM
DEVELOPMENT MAY OCCUR OVER THE TX S PLNS OR PERMIAN BASIN AS VORT
MAX NOW ROUNDING BASE OF LARGER SCALE TROUGH NEAR LAS APPROACHES THE
SRN HI PLNS. SUCH ACTIVITY...IF IT WERE TO DEVELOP...COULD BE
ACCOMPANIED BY A LIMITED THREAT FOR MARGINALLY SVR HAIL. DOWNSTREAM
FROM THE VORT...MORE ELEVATED EARLY MORNING CONVECTION/ACCAS COULD
SPREAD/DEVELOP NNEWD INTO NW TX/WRN OK.
...CNTRL HI PLNS...
SCTD AFTN/EVE STORMS ALSO EXPECTED TO FORM IN AREA OF ENHANCED LOW
LVL CONVERGENCE/SE FLOW N OF LEE CYCLONE IN ERN WY/NE CO AND FAR WRN
PARTS OF THE NEB PANHANDLE. THE MEAN WIND IN THIS REGION WILL BE
WEAKER RELATIVE TO W TX...AND MOISTURE WILL BE SPARSE. BUT STEEP
LAPSE RATES MAY YIELD SMALL HAIL/GUSTY WINDS IN A FEW SPOTS.
..CORFIDI/JEWELL.. 04/15/2009
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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