Jun 8, 2011 1630 UTC Day 1 Convective Outlook | |
Updated: Wed Jun 8 16:30:10 UTC 2011 | |
Probabilistic to Categorical Outlook Conversion Table |
Categorical Graphic |
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Probabilistic Tornado Graphic |
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Probability of a tornado within 25 miles of a point. Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point. |
Probabilistic Damaging Wind Graphic |
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Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point. Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point. |
Probabilistic Large Hail Graphic |
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Probability of hail 1" or larger within 25 miles of a point. Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point. |
SPC AC 081626 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1126 AM CDT WED JUN 08 2011 VALID 081630Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NEW ENGLAND INTO THE GREAT LAKES AND THEN SWWD INTO THE CENTRAL PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS NEAR THE NERN CO FOOTHILLS... ..NERN PA/ERN NY INTO NRN NEW ENGLAND... STRONG HEATING OF MOISTENING BOUNDARY LAYER WILL RESULT IN MLCAPES UP TO 2000 J/KG. THIS INSTABILITY AND DEEP LAYER SHEAR AT 30-40 KT WILL BE FAVORABLE FOR MULTICELLS WITH HAIL/DAMAGING WINDS. HOWEVER...BUILDING 500 MB HEIGHTS AND CAPPING INVERSION ARE EXPECTED TO LIMIT CONVECTIVE DEVELOPMENT. THE BEST CHANCES FOR STORMS WILL BE IN MAINE LATER THIS AFTERNOON AS SHORTWAVE TROUGH...CURRENTLY OVER QUEBEC...SHIFTS EWD ACROSS AT LEAST NRN ME. AS THE RIDGE BREAKS DOWN IN THE NERN STATES LATER TODAY... STORMS LOCATED OVER LOWER MI REGION MAY MOVE EWD INTO PORTIONS OF NRN/WRN NY THIS EVENING. ELSEWHERE...STORMS ARE EXPECTED TO BE TOO ISOLATED FOR A SLIGHT RISK ISSUANCE. ...GREAT LAKES TO IA/NRN MO SWWD INTO NERN KS... LIGHTNING HAS BEEN DECREASING IN STORMS IN IA...THOUGH NEW STORMS HAVE RECENTLY DEVELOPED IN ERN WI. THESE STORMS APPEAR TO STILL BE SLIGHTLY ELEVATED...BUT MAY CONTINUE WITH A SEVERE POTENTIAL AS THEY SHIFT EWD INTO LOWER MI THIS AFTERNOON. ELSEWHERE ACROSS AREA...AT MID MORNING...COLD FRONT STRETCHED FROM THE FAR WRN U/P SWWD INTO NRN KS. STRONG HEATING AHEAD OF SEWD MOVING FRONT WILL RESULT IN AIR MASS TO BECOME MODERATELY TO STRONGLY UNSTABLE. SMALL CLUSTERS OF SURFACE BASED STORMS ARE FORECAST TO DEVELOP ALONG AND AHEAD OF THE FRONT. THE STRONGER WINDS ALOFT WILL REMAIN BEHIND THE FRONT...THE DEEP LAYER SHEAR WILL BE MOST FAVORABLE FOR MULTICELLS. HOWEVER...SUPERCELL STRUCTURES ARE POSSIBLE OVER THE WRN GREAT LAKES...WHERE EFFECTIVE BULK SHEAR WILL BE STRONGER...AND PERHAPS SWWD INTO IA WHERE INSTABILITY WILL BE QUITE STRONG. LARGE HAIL...AND DAMAGING WINDS WILL BE POSSIBLE WITH STRONGER STORMS AND A BRIEF TORNADO OR TWO. ...CENTRAL KS SWWD INTO NWRN OK... DESPITE A RELATIVELY DRY BOUNDARY LAYER...DEWPOINTS MOSTLY IN THE 40S TO LOWER 50S...COMBINATION OF STRONG SURFACE HEATING AND SURFACE CONVERGENCE ALONG SEWD MOVING COLD FRONT MAY BE ENOUGH FOR A FEW STORMS TO DEVELOP NEAR THE FRONT LATE AFTERNOON. FORECAST SOUNDINGS INDICATE ANY STORMS THAT DEVELOP WILL BE HIGH BASED AND SUPPORTIVE OF SEVERE WINDS. THE THREAT SHOULD DISSIPATE QUICKLY AFTER SUNSET WITH LOSS OF DAYTIME HEATING. ...CENTRAL PLAINS... SURFACE HIGH PRESSURE WILL BUILD INTO PORTIONS OF WRN CENTRAL PLAINS AS COLD FRONT MOVES SWD INTO THE TX PANHANDLE AND EWD THROUGH CENTRAL KS. BOUNDARY LAYER MOISTURE HAS DRIED OUT WITH PASSAGE OF FRONT AND WITH LACK OF DYNAMICAL FORCING...SEVERE PROBABILITIES HAVE BEEN LOWERED ACROSS NEB/NERN CO AND SERN WY. FARTHER SOUTH ACROSS THE NERN CO FOOTHILLS...THERE MAY BE ENOUGH MOISTURE IN ELY UPSLOPE FLOW FOR A STORM OR TWO DEVELOP LATE AFTERNOON. ANY STORMS THAT DEVELOP WILL HAVE SUFFICIENT SHEAR TO ROTATE. THE RELATIVELY DRY BOUNDARY LAYER INDICATES THAT SEVERE HAIL WOULD BE THE PRIMARY THREAT. ...GREAT BASIN... HIGH BASED STORMS WITH GUSTY WINDS ARE LIKELY THIS AFTERNOON AHEAD OF APPROACHING UPPER TROUGH. SEVERE COVERAGE ATTM IS EXPECTED TO BE ISOLATED. ...LOWER/MID MS VALLEY REGION... THUNDERSTORMS SHOULD ONCE AGAIN DEVELOP IN MOIST AIR MASS WITHIN VERY WEAKLY SHEARED ENVIRONMENT. AIR MASS DOES APPEAR A LITTLE MORE STABLE THAN TUE...ESPECIALLY ACROSS MS...BUT PULSE TYPE SEVERE STORMS ARE POSSIBLE. ISOLATED SEVERE STORMS ALSO POSSIBLE ACROSS NERN AR/SERN MO LATER TODAY AHEAD OF WEAK MCV. ..IMY/SMITH.. 06/08/2011 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z