| 
)| Categorical Graphic | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
|||||||||
| 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. |
|||||||||
| 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. |
|||||||||
| 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. |
|||||||||
| |||||||||
SPC AC 081241 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 AM CDT THU AUG 08 2013 VALID 081300Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE SRN PLNS... ...SYNOPSIS... PATTERN WILL REMAIN LARGELY UNCHANGED THIS PERIOD...AS ELONGATED UPR LOW PERSISTS OVER WRN ONT AND A WEAKER LOW LINGERS OVER THE NRN CA CST. SEASONABLY STRONG CYCLONIC FLOW WILL CONTINUE ACROSS THE UPR MS VLY AND UPR GRT LKS ALONG SRN SIDE OF THE ONT LOW. FARTHER S...BELT OF SOMEWHAT ENHANCED SW TO WSWLY FLOW WILL CONTINUE FROM AZ/NM ACROSS THE SRN PLNS INTO THE LWR OH VLY. A WEAK DISTURBANCE IN THIS FLOW...NOW CENTERED OVER SRN CO...SHOULD SHEAR ENE ACROSS KS LATER TODAY AND INTO MO EARLY FRI. AT LWR LVLS...DIFFUSE W-E FRONT WILL REMAIN NEARLY STNRY FROM THE TX PANHANDLE THROUGH CNTRL OK INTO NRN AR...WHILE ERN PART OF SAME BOUNDARY ADVANCES SLOWLY E/SE AS A WEAK COLD FRONT OVER THE LWR GRT LKS. OUTFLOW BOUNDARIES FROM OVERNIGHT STORMS LIKELY WILL BE PRESENT S OF SYNOPTIC FRONT IN THE SRN PLNS. ...SRN PLAINS TO OZARKS TODAY/TNGT... LARGE MCS AND RELATED STORMS/MCV SHOULD CONTINUE TO WEAKEN OVER PARTS OF KS...MO...OK...AND AR THROUGH LATER THIS MORNING. CLOUD DEBRIS LIKELY WILL LEAVE A ROUGHLY W-E DIFFERENTIAL HEATING BOUNDARY OVER CNTRL/NRN PARTS OF OK AND AR THAT WILL LOCALLY REINFORCE WEAK SYNOPTIC BOUNDARY ALREADY IN PLACE. DAYTIME HEATING/LOW-LVL DESTABILIZATION SHOULD THEREFORE BE GREATEST A BIT FARTHER S AND W...ROUGHLY FROM THE TX PANHANDLE EWD ALONG I-40 INTO OK. HEATING SHOULD INITIATE ANOTHER ROUND OF TSTMS BY EARLY AFTN IN WEAKLY-CAPPED ENVIRONMENT ALONG THE BOUNDARY...ESPECIALLY NEAR ITS INTERSECTION WITH N/S LEE TROUGH IN W TX AND THE TX PANHANDLE. ADDITIONAL STORMS ALSO SHOULD FORM OVER NE NM...SE CO...AND SW KS...IN WEAK UPSLOPE FLOW N OF FRONT. GIVEN 25-30 KT WSWLY MID-LVL WINDS...E TO SELY LOW-LVL FLOW...AND WEAK FORCING FOR ASCENT PROVIDED BY SRN EXTENSION OF CO UPR IMPULSE...SETUP SHOULD PROVE FAVORABLE FOR A COMPLEX MIX OF LOOSELY-ORGANIZED STORM CLUSTERS THAT MAY INCLUDE TRANSIENT ROTATING STRUCTURES AND EMBEDDED LEWPS...IN ADDITION TO MULTICELLS...CAPABLE OF SVR WIND/HAIL. CONTINUED NEWD ADVANCE OF UPR IMPULSE...AND ASSOCIATED VEERING OF MID-LVL WINDS...SHOULD ENCOURAGE UPSCALE GROWTH INTO A LARGE MCS/POSSIBLE MCC TNGT...WITH A CONTINUING /THOUGH SPORADIC/ RISK FOR BOWING SEGMENTS AND LOCALLY DMGG WIND OVER PARTS OF OK...SRN KS...SRN MO...AND NRN AR TNGT/EARLY FRI. ...UPSTATE NY TO NRN NEW ENGLAND THIS AFTN... CLOUDS AND ONGOING STORMS WILL DIMINISH SFC HEATING/DESTABILIZATION IN CORRIDOR OF 60S TO LWR 70S SFC DEW POINTS ALONG/AHEAD OF WEAK COLD FRONT NOW APPROACHING THE LWR GRT LKS. SATELLITE DATA AND MODEL FCSTS SUGGEST THAT IN WAKE OF STRONGER UPR IMPULSE THAT MOVED ACROSS THE REGION LATE YESTERDAY...HEIGHTS WILL SLIGHTLY REBOUND IN THE 30-35 KT MID-LVL WLY FLOW ON SE SIDE OF ONT UPR LOW. NEVERTHELESS...WHILE FORCING FOR ASCENT WILL BE WEAK...POCKETS OF ENHANCED INSOLATION SHOULD YIELD SUFFICIENT BUOYANCY FOR ISOLD TO SCTD AFTN MULTICELL STORMS...ESPECIALLY WRN/NRN NY INTO NRN NEW ENGLAND. A FEW OF THESE COULD YIELD LOCALLY DMGG WIND/MARGINALLY SVR HAIL. ...CNTRL/NRN NRN HIGH PLNS INTO SD/NRN NEB THIS AFTN/EVE... WEAK UPSLOPE FLOW ASSOCIATED WITH A SECONDARY FRONTAL SURGE INTO THE NRN PLNS...ALONG WITH DAYTIME HEATING...MAY PROMOTE ISOLD TSTMS OVER/NEAR THE HIGHER TERRAIN OF SRN MT...NRN AND ERN WY...AND WRN SD...AND ALONG WEAK FRONT/MOIST AXIS EXTENDING E ACROSS SRN SD. 30-35 KT WNWLY DEEP SHEAR ON SW FRINGE ON ONT UPR LOW AND FAIRLY STEEP MID-LVL LAPSE RATES COULD YIELD A FEW INSTANCES OF MARGINALLY SVR HAIL/WIND. ...NRN CA/SRN ORE/NW NV THIS AFTN/EVE... COOL TEMPERATURES /-12 TO -16 DEG C/...ENHANCED /25-30 KT/ SELY FLOW...AND DCVA WILL OVERSPREAD NRN CA...NW NV...AND WRN/SRN ORE AT 500 MB LATER TODAY AS NEG-TILT VORT LOBE ASSOCIATED WITH NRN CA CSTL LOW APPROACHES REGION. COUPLED WITH SFC HEATING...SETUP COULD YIELD SCTD STORMS OVER THE CASCADES AND NRN SIERRA CAPABLE OF MARGINALLY SVR HAIL/WIND. ..CORFIDI/COHEN.. 08/08/2013 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z |