| Sep 2, 2012 0100 UTC Day 1 Convective Outlook | |
| Updated: Sun Sep 2 00:54:30 UTC 2012 | |
| 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 020051 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT SAT SEP 01 2012 VALID 020100Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE INTERMOUNTAIN WEST... ...MID MS VALLEY... A NEARLY UNBROKEN LINE OF STRONG THUNDERSTORMS IS CURRENTLY ONGOING ALONG THE ERN EDGE OF A CLOSED-OFF LOW EVIDENT ON WATER VAPOR IMAGERY CENTERED OVER ERN MO. THE LINE IS BEING SUPPORTED BY A BAND OF STRONG LARGE-SCALE ASCENT TO THE EAST OF THE UPPER-LEVEL LOW. THE LINE IS ALSO LOCATED ALONG AN AXIS OF MODERATE INSTABILITY WHERE SBCAPE IS ESTIMATED AROUND 1000 J/KG IN WRN KY TO ABOVE 2000 J/KG IN SERN AR. THE INSTABILITY AND STRONG LARGE-SCALE ASCENT SHOULD ENABLE THE LINE TO BE MAINTAINED THROUGH MUCH OF THE EVENING MOVING EWD ACROSS NRN MS...WRN TN AND WRN KY. IN ADDITION...MESOANALYSIS SHOWS A WELL-DEFINED 40 TO 50 KT LOW TO MID-LEVEL JET WRAPPING AROUND THE SRN EDGE OF THE UPPER-LEVEL LOW. THE EXIT REGION OF THE JET CURRENTLY INTERSECTS THE LINE OF STORMS IN SRN IL. THE COMBINATION OF SHEAR AND INSTABILITY APPEARS TO BE MAXIMIZED A BIT FURTHER TO THE EAST ACROSS WRN KY AND WRN TN WHERE A THREAT FOR SUPERCELLS EMBEDDED IN THE LINE SHOULD CONTINUE THIS EVENING. THE WSR-88D VWP AT PADUCAH SHOWS IMPRESSIVE LOW-LEVEL SHEAR WITH 0-1 KM SHEAR OF 40 KT AND GRADUALLY VEERING OF THE WINDS WITH HEIGHT FROM THE SFC TO 3 KM. THIS LOW-LEVEL SHEAR ENVIRONMENT SHOULD CONTINUE TO SUPPORT A TORNADO THREAT WITH ROTATING STORMS THAT PERSIST THIS EVENING. WIND DAMAGE WILL ALSO LIKELY ACCOMPANY FAST-MOVING BOWING LINE SEGMENTS. THE TORNADO THREAT MAY NOT BE AS GREAT FARTHER TO THE SOUTHWEST ACROSS ERN AND SRN AR WHERE THE SFC WINDS ARE VEERED. HOWEVER...MLCAPE VALUES ABOVE 2000 J/KG IN SERN AR AND NW MS ALONG WITH STEEP LOW-LEVEL LAPSE RATES SHOULD BE FAVORABLE FOR DAMAGING WIND GUSTS AS THE LINE MOVES EWD ACROSS THE SLIGHT RISK AREA THIS EVENING. ...INTERMOUNTAIN WEST... THE LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-LEVEL TROUGH OVER THE NRN ROCKIES WITH A PRONOUNCED DRY INTRUSION LOCATED ACROSS THE INTERMOUNTAIN WEST. JUST TO THE UPSTREAM OF THE DRY SLOT...NUMEROUS THUNDERSTORMS ARE ONGOING FROM SRN MT SWD INTO NRN UT WHERE MESOANALYSIS HAS SEVERAL POCKETS OF MODERATE INSTABILITY. ALTHOUGH REGIONAL WSR-88D VWPS SHOW UNIDIRECTIONAL WIND PROFILES...SUBSTANTIAL SPEED SHEAR IS PRESENT IN THE LOW TO MID-LEVELS WHICH IS HELPING TO CREATE 50 TO 60 KT OF DEEP LAYER SHEAR ACROSS MUCH OF THE REGION. THE STRONGLY SHEARED ENVIRONMENT SHOULD CONTINUE TO SUPPORT SUPERCELL DEVELOPMENT THIS EVENING AS THE CELLS MOVE QUICKLY NEWD ACROSS SE ID...NRN UT AND INTO WRN WY. LARGE HAIL WILL BE POSSIBLE WITH SUPERCELLS BUT A WIND DAMAGE THREAT SHOULD ALSO EXIST ESPECIALLY WITH ANY MULTICELL CLUSTERS THAT CAN PERSIST OVER THE NEXT FEW HOURS. ..BROYLES.. 09/02/2012 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z