May 24, 2013 1630 UTC Day 1 Convective Outlook | |||||||||
Updated: Fri May 24 16:29:35 UTC 2013 | |||||||||
Probabilistic to Categorical Outlook Conversion Table |
Categorical Graphic | |||||||||
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Probabilistic Tornado Graphic | |||||||||
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. |
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Probabilistic Damaging Wind Graphic | |||||||||
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. |
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Probabilistic Large Hail Graphic | |||||||||
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. |
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SPC AC 241625 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1125 AM CDT FRI MAY 24 2013 VALID 241630Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL AND SRN HIGH PLAINS... ...SYNOPSIS... A PROMINENT MID TO UPPER-LEVEL LOW WILL BE MAINTAINED THROUGH THE D1 PERIOD OVER THE PACIFIC NW AND SRN BC/AB...RESULTING IN A SWLY FLOW REGIME ACROSS THE INTERMOUNTAIN WEST INTO NRN/CNTRL PLAINS. AN EMBEDDED VORTICITY MAXIMUM OVER THE NRN HIGH PLAINS WILL PIVOT NEWD TODAY WHILE A SERIES OF WEAKER PERTURBATIONS TRANSLATE THROUGH THE GREAT BASIN INTO NRN/CNTRL HIGH PLAINS. DOWNSTREAM FROM THESE DEVELOPMENTS...THE SRN PORTION OF AN AMPLIFIED MIDLEVEL TROUGH FROM ERN CANADA INTO THE CNTRL/SRN APPALACHIANS WILL PROGRESS EWD/NEWD TO OFF THE MID-ATLANTIC COAST BY SATURDAY MORNING. IN THE LOW LEVELS...THE PREVAILING SWLY MIDLEVEL FLOW REGIME ACROSS THE ROCKIES WILL MAINTAIN A LEE LOW OVER THE CNTRL HIGH PLAINS WITH A LEE TROUGH/DRYLINE EXTENDING SWD INTO SWRN TX. ...CNTRL/SRN HIGH PLAINS THIS AFTERNOON AND EVENING... THE LARGE-SCALE PATTERN WILL SUSTAIN A SLY LLJ ACROSS THE NRN/CNTRL PLAINS TODAY WHICH WILL ENHANCE THE NWD FLUX OF AN INCREASINGLY MOIST PBL CHARACTERIZED BY DEWPOINTS IN THE UPPER 50S TO LOWER 60S. THIS PROCESS WILL OCCUR BENEATH AN EML WHERE 700-500-MB LAPSE RATES OF 8.0-9.5 C/KM WERE OBSERVED BY 12Z REGIONAL RAOBS. WHEN COUPLED WITH DAYTIME HEATING...THE ENVIRONMENT IS EXPECTED TO BECOME MODERATELY UNSTABLE BY AFTERNOON WITH MLCAPE VALUES APPROACHING 1000-2000 J/KG. LATEST MODEL GUIDANCE SUGGESTS THAT LARGE-SCALE FORCING FOR ASCENT WILL REMAIN NEGLIGIBLE THROUGH THE PEAK OF THE DIURNAL HEATING CYCLE WITH LITTLE CHANGE TO THE 500-MB HEIGHT FIELD. THERE IS SOME INDICATION IN CURRENT WATER VAPOR IMAGERY THAT A WEAK PERTURBATION MAY BE MOVING INTO THE FOUR CORNERS REGION...WHICH MAY APPROACH THE DISCUSSION AREA THIS EVENING. IN GENERAL...IT APPEARS THAT STRONG HEATING ALONG THE DRYLINE/LEE TROUGH --AND PERHAPS SOME WEAK UPSLOPE COMPONENT-- WILL BE THE PRIMARY MECHANISM/S/ INITIATING ISOLATED STORMS LATER THIS EVENING. FORECAST HODOGRAPHS VALID 25/00Z EXHIBIT 20-30 KT SSELY LOW-LEVEL WINDS VEERING TO WLY AT 25-30 KT IN THE MIDLEVELS WHICH WILL BE SUPPORTIVE OF SUPERCELL DEVELOPMENT GIVEN THE MODERATE INSTABILITY. WHILE LARGE HAIL WILL BE THE PRIMARY HAZARD...A TORNADO OR TWO IS POSSIBLE...AS ARE LOCALLY DAMAGING WIND GUSTS. STORMS MAY CONGEAL INTO CLUSTERS LATER THIS EVENING BEFORE WEAKENING TONIGHT AS THE PBL COOLS AND STABILIZES. ...SRN TX THIS AFTERNOON AND EVENING... A NOCTURNAL MCS HAS GENERATED A WELL-DEFINED MCV /PER RADAR DATA/ OVER THE EDWARDS PLATEAU WHICH SHOULD SLOWLY DRIFT EWD/SEWD TODAY. FORCING ASSOCIATED WITH THIS FEATURE AND LOW-LEVEL UPLIFT ALONG RESIDUAL OUTFLOW BOUNDARIES WILL PROMOTE AN INCREASE IN STORMS THIS AFTERNOON ACROSS THE EDWARDS PLATEAU AND HILL COUNTRY INTO THE BRUSH COUNTRY. WHILE VERTICAL SHEAR WILL REMAIN WEAK...THE PRESENCE OF A MOIST AND MODERATELY UNSTABLE ENVIRONMENT WILL BE SUPPORTIVE OF VIGOROUS STORMS WITH A RISK FOR LOCALLY DAMAGING WINDS OWING TO WATER-LOADED DOWNDRAFTS. ..MEAD/MOSIER.. 05/24/2013 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z |