SPC AC 151259
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0659 AM CST FRI FEB 15 2008
VALID 151300Z - 161200Z
...THERE IS A SLGT RISK OF SVR TSTMS A LARGE PORTION OF TX...
...SYNOPSIS...
PATTERN WILL REMAIN PROGRESSIVE ACROSS THE LWR 48 THIS PERIOD...WITH
MAIN BELT OF THE WLYS CONTINUING ACROSS SRN CANADA AND GRT LKS/NERN
STATES. UPR LOW NOW CENTERED NEAR YUM SHOULD CONTINUE E INTO SE AZ
THIS EVENING AND REACH THE ELP AREA BY 12Z SATURDAY.
AT THE SFC...SHALLOW COLD FRONT WILL MOVE STEADILY S ACROSS W TX
TODAY...CROSSING THE BIG BEND REGION INTO NRN MEXICO. FARTHER
E...EXPECT THAT THE FRONT WILL MOVE MORE SLOWLY ACROSS CNTRL AND NE
TX. THE BOUNDARY SHOULD BECOME STATIONARY FROM E OF DAL TO NEAR TPL
TO SE OF DRT BY THE END OF THE PERIOD AS CYCLONE SLOWLY DEEPENS SE
OF DRT. FARTHER E...DIFFUSE WARM FRONT MARKING LEADING EDGE OF
GULF/MARITIME AIR EXPECTED TO DRIFT SLOWLY NE...REACHING A
TPL/CLL/BPT AXIS BY 12Z SATURDAY.
...S CNTRL INTO E TX...
WELL-DEFINED EML DEPICTED ON MORNING SOUNDINGS ACROSS WRN/SRN TX
SUGGEST THAT MUCH OF THE STATE LIKELY WILL REMAIN CAPPED TO DEEP
MOIST CONVECTION THROUGH THE DAY...DESPITE SFC HEATING...ADVANCE OF
AFOREMENTIONED COLD FRONT...AND PASSAGE OF WEAK IMPULSES IN SWLY UPR
FLOW DOWNSTREAM FROM AZ UPR LOW. A FEW SFC-BASED STORMS
MAY...HOWEVER...FORM IN THE MOUNTAINS OF COAHUILA STATE IN N CNTRL
MEXICO...WHERE SUSTAINED UPSLOPE FLOW AND ELEVATED HEAT SOURCE MAY
OVERCOME INCREASING POST-FRONTAL CIN. IF SUCH STORMS DO INDEED
FORM...A CONDITIONAL THREAT FOR LARGE HAIL/HIGH WINDS AND POSSIBLY A
TORNADO COULD EXTEND E/NE ACROSS THE RIO GRANDE TO NEAR DRT AS
STORMS MOVE/PROPAGATE ALONG STALLING SEGMENT OF FRONT LATE IN THE
DAY THROUGH EARLY TONIGHT.
FARTHER E...INCREASING WARM ADVECTION/MOISTURE INFLOW MAY SUPPORT
WIDELY SCTD CONVECTIVE DEVELOPMENT LATE IN THE PERIOD INVOF
SLOWLY-ADVANCING WARM FRONT OVER E CNTRL/NE TX. ATTM IT APPEARS
THAT DEGREE OF LIFT MAY NOT BE SUFFICIENT TO OVERCOME SUBSTANTIAL
EML CIN THAT WILL EXIST ACROSS REGION. NEVERTHELESS...GIVEN
SEASONABLY RICH MOISTURE ALREADY IN PLACE OVER THE NWRN GULF AND
ALONG THE TX GULF CST /AOA 1.25 IN PER BLENDED PW DATA/ AND LIKELY
STRENGTHENING/BROADENING OF LLJ ACROSS REGION AFTER 09Z... WILL
MAINTAIN A LOW PROBABILITY RISK FOR SLIGHTLY ELEVATED STORMS WITH
HAIL.
...W TX...NW OF STALLING FRONT...
TSTM POTENTIAL MORE DIRECTLY ASSOCIATED WITH APPROACHING UPR LOW
WILL SHIFT E FROM AZ/NM INTO W TX AFTER 06Z SATURDAY AS LEADING EDGE
OF DPVA REACHES INCREASINGLY RICH ELEVATED MOISTURE AXIS ABOVE
SHALLOW FRONT. STORM COVERAGE AND INTENSITY MAY INCREASE MOST
MARKEDLY AFTER ABOUT 09Z FROM THE BIG BEND REGION NWD ACROSS THE LOW
ROLLING PLAINS INTO PARTS OF NW TX AS MUCAPE INCREASES TO BETWEEN
500 AND 1000 J/KG ON WRN FRINGE OF STRENGTHENING LLJ. COUPLED WITH
INCREASING MID/UPR LEVEL WINDS /60 + KT SSW FLOW AT 500 MB/
FLOW...SETUP LIKELY WILL BECOME FAVORABLE FOR ELEVATED SUPERCELLS
WITH LARGE HAIL.
..CORFIDI.. 02/15/2008
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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