SPC AC 161622
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1122 AM CDT SUN MAY 16 2010
VALID 161630Z - 171200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE S CNTRL
U.S....
...SRN PLAINS...
WEAK UPPER LOW SWRN NEB WITH TROUGH SWD TO TX PANHANDLE CONTINUES
ESEWD TO LWR MO/MS VALLEY BY 12Z MON. LITTLE IN THE WAY OF SURFACE
REFLECTION OF TROUGH AS LOWER TROP FLOW GENERALLY WEAK OVER MUCH OF
TX/OK. HOWEVER WITH THE RELATIVELY COLD/STEEP MID LEVEL LAPSE RATES
ACCOMPANYING UPPER SYSTEM AND MOIST BOUNDARY LAYER...WHERE HEATING
CAN OCCUR THUNDERSTORMS WILL BE ABLE TO DEVELOP BY MID AFTERNOON AS
TEMPS RISE TO 80F OR ABOVE.
THERE IS A SURFACE BOUNDARY EXTENDING FROM DECAYING MCS OVER SRN KS
SWWD THRU FAR NWRN OK AND ACROSS THE TX PANHANDLE. LOOK LIKE CLOUDS
WILL HOLD IN ALONG KS/OK BORDER WHILE CURRENTLY MUCH OF WRN OK
HEATING UP WELL. THUS FOCUS FOR ORGANIZED THUNDERSTORMS EXPECTED TO
DEVELOP E/SE ACROSS MUCH OF NRN/CENTRAL OK THIS AFTERNOON ASSOCIATED
BOTH WITH THE LOW LEVEL CONVERGENCE WITH THE SEWD MOVING BOUNDARY
AND THE ZONE OF DIFFERENTIAL HEATING TAKING PLACE S OF KS/OK BORDER.
WITH ABOUT 30KT OF DEEP LAYER SHEAR AND MLCAPES AOA 2000 J/KG STORM
MODE INITIALLY MULTICELL VICINITY BOUNDARIES...BECOMING MORE LINEAR
LATER THIS AFTERNOON/EVENING. LARGE HAIL WILL BE PRIMARY THREAT
GIVEN THE COOL/STEEP MID LEVEL LAPSE RATES WITH SOME WIND DAMAGE
CONCERN AS STORMS BECOME MORE OUTFLOW DOMINATED. HAVE SHIFTED THE
EARLIER HIGHER HAIL PROBS NEWD BASED ON THE ABOVE SCENARIO.
FURTHER S AND E ACROSS AR AND TX...STORMS SHOULD BECOME COMMON BY
MID/LATE AFTERNOON AS CINH DISSIPATES MUCH OF AREA. HOWEVER LACK OF
FOCUS AND WEAK SHEAR MAKES IT DIFFICULT TO PINPOINT AN AREA OF AN
ORGANIZED SEVERE THREAT. HOWEVER LARGE HAIL AND BRIEF DAMAGING WINDS
WILL BE POSSIBLE IN THE STRONGER STORMS GIVEN ADEQUATE SHEAR AND MID
LEVEL LAPSE RATES AROUND 7C/KM.
...SERN STATES...
STRONG STORMS WILL FORM WITH DAYTIME HEATING ALONG/S OF THE RESIDUAL
FRONTAL ZONE/SFC LOW OVER REGION. MODEST DEEP SHEAR AND MOIST
ENVIRONMENT MAY SUPPORT UPSCALE DEVELOPMENT INTO BANDS/SMALL
CLUSTERS WITH LOCALLY DMGG WIND/MARGINALLY SVR HAIL.
WILL MAINTAIN MARGINAL SEVERE PROBABILITIES GIVEN LIMITED SHEAR AND
MID LEVEL LAPSE RATES LESS THAN 7C/KM.
...ORE/SRN WA...
SUBSTANTIAL HEIGHT FALLS WILL OVERSPREAD THE PACIFIC NORTHWEST LATER
TODAY/TONIGHT AS MULTIPLE MID LVL IMPULSES CROSS REGION AHEAD OF
AMPLIFYING OFFSHORE TROUGH. SUFFICIENT MOISTURE/ INSTABILITY AND
MODERATELY STRONG/LARGELY UNIDIRECTIONAL SSW WIND FIELD MAY YIELD
SOME STRONG/SVR TSTMS WITH HAIL/GUSTY WINDS VICINITY ORE CASCADES BY
LATER THIS AFTERNOON...SPREADING NWD TO WA CASCADES THIS EVENING.
..HALES/HURLBUT.. 05/16/2010
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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