SPC AC 131617
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1117 AM CDT TUE APR 13 2010
VALID 131630Z - 141200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NORTHERN/CENTRAL
HIGH PLAINS...
...NRN AND CENTRAL PLAINS...
COLD TROUGH OVER THE INTERMOUNTAIN REGION THIS MORNING IN THE
PROCESS OF LIFTING NEWD WITH EXPECTED DEEPENING UPPER LOW INTO
CENTRAL MT TONIGHT. ASSOCIATED 100 PLUS KT POLAR JET AZ-CO WILL
SHIFT NEWD WITH THE TROUGH INTO CENTRAL AND NRN HIGH PLAINS THIS
AFTERNOON/EVENING AS STRONG COLD FRONT EMERGES FROM ROCKIES INTO
HIGH PLAINS.
WITH HIGH PRESSURE HOLDING OVER THE ERN US INTO NRN GULF...ONLY
LIMITED GULF MOISTURE HAS BEEN ABLE TO RETURN IN THE STRONG SLY FLOW
ACROSS THE HIGH PLAINS. EVEN WITH STEEP LAPSE RATES TO 8C/KM
DEVELOPING IN ADVANCE OF THE COLD FRONT...DEWPOINTS ONLY INTO THE
40S/LOW 50S WHILE RESULT IN MLCAPES NO HIGHER THAN 500 J/KG MUCH OF
WARM SECTOR.
WITH STRONG PRIMARILY UNIDIRECTIONAL FLOW IN THE MARGINALLY UNSTABLE
WARM SECTOR...THE FORCING WITH THE COLD FRONT EXPECTED TO BE FOCUS
FOR SEVERE THUNDERSTORM DEVELOPMENT. THE COMBINATION OF 40-50KT
SFC-1KM SHEAR AND CONVECTIVE CONTRIBUTION FROM THE DEVELOPING LINE
OF STORMS SHOULD LEAD TO A BAND OF STRONG/DAMAGING WIND GUSTS BY
EARLY/MID AFTERNOON WRN DAKOTAS/WRN NEB/NERN CORNER CO.
EMBEDDED MORE INTENSE SEGMENTS ARE POSSIBLE WITHIN THE SQUALL LINE
BY MID/LATE AFTERNOON...INCREASING WIND DAMAGE POTENTIAL AND EVEN
THE POSSIBILITY OF A BRIEF TORNADO OR TWO. ACCORDINGLY WIND DAMAGE
PROBABILITY HAS BEEN INCREASED THIS AREA.
BY LATE EVENING MUCH OF THE AVAILABLE INSTABILITY WILL BE NEGLIGIBLE
VIA A DECOUPLING/CONVECTIVELY OVERTURNED BOUNDARY LAYER...LEADING TO
A DECREASE IN THE DAMAGING WIND THREAT.
...SOUTHERN HIGH PLAINS...
WITHIN A MORE SUBTLY FORCED LARGE SCALE REGIME...MODESTLY MOIST LOW
LEVEL UPSLOPE WILL CONTRIBUTE TO ISOLATED STRONG/PERHAPS SEVERE
STORMS ACROSS PORTIONS OF EASTERN NM AND FAR WEST/SOUTHWEST TX THIS
AFTERNOON/EARLY EVENING. SUFFICIENT VEERING COULD YIELD SOME
SEMI-SUSTAINED STORMS/MARGINAL SUPERCELLS...WITH SEVERE HAIL AS THE
PRIMARY CONCERN ON AN ISOLATED BASIS.
..HALES/JEWELL.. 04/13/2010
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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