DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1244 AM CDT SUN JUL 26 2015 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF EASTERN MONTANA/WESTERN NORTH DAKOTA... ...THERE IS A MRGL RISK OF SVR TSTMS SURROUNDING THE SLIGHT RISK AREA OVER PORTIONS OF THE CENTRAL/NORTHERN PLAINS AND UPPER MIDWEST... ...SUMMARY... SEVERE THUNDERSTORMS WILL BE POSSIBLE MONDAY OVER PORTIONS OF THE CENTRAL AND NORTHERN PLAINS AND UPPER MIDWEST. ...SYNOPSIS... A SEASONABLY STRONG UPPER TROUGH WILL MOVE ACROSS THE NORTHERN ROCKIES MONDAY AS A WEAK TROUGH MOVES SLOWLY EASTWARD ALONG THE EAST COAST. SURFACE LOW PRESSURE WILL DEEPEN FROM EASTERN MONTANA INTO WESTERN NORTH DAKOTA AS AN ASSOCIATED COLD FRONT MOVES ACROSS THE NORTHERN PLAINS. ...CENTRAL/NORTHERN PLAINS INTO UPPER MIDWEST... A FEW ELEVATED STRONG/SEVERE STORMS MAY BE IN PROGRESS EARLY MONDAY ACROSS NORTHEAST MONTANA/NORTHWEST NORTH DAKOTA AS A LEAD SHORTWAVE TROUGH LIFTS NORTHEAST IN ADVANCE OF THE PRIMARY UPPER LEVEL TROUGH. LARGE HAIL WOULD BE THE MAIN THREAT WITH EARLY DAY STORMS. AS THE SURFACE LOW DEEPENS OVER EASTERN MONTANA DURING THE DAY...A MOIST LOW-LEVEL EASTERLY FLOW /SURFACE DEW POINTS 60-65/ WILL DEVELOP NORTH OF THE LOW AND A FRONTAL BOUNDARY EXTENDING NORTHEAST FROM THE LOW INTO NORTH-CENTRAL NORTH DAKOTA. WITH STEEP MID-LEVEL LAPSE RATES IN PLACE...MODERATE/STRONG SURFACE-BASED INSTABILITY SHOULD EXIST BY AFTERNOON. STRENGTHENING MID-LEVEL FLOW ABOVE LOW-LEVEL EASTERLIES WILL RESULT IN A STRONGLY SHEARED ENVIRONMENT /0-6 KM SHEAR 45-55 KTS/. AS HEIGHT FALLS/FORCING FOR ASCENT OVERSPREAD THE AREA DURING THE AFTERNOON...THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER NORTHEAST MONTANA/NORTHWEST NORTH DAKOTA WITH SUPERCELLS LIKELY AND A RISK FOR LARGE HAIL AND DAMAGING WINDS. DESPITE MARGINAL LCL HEIGHTS...SOME TORNADO RISK MAY EXIST WHERE BACKED LOW-LEVEL FLOW CONTRIBUTES TO ENHANCED 0-3 KM STORM-RELATIVE HELICITY. FARTHER SOUTH...THUNDERSTORM DEVELOPMENT IS POSSIBLE DURING THE AFTERNOON IN ADVANCE OF THE COLD FRONT ALONG A NORTH-SOUTH SURFACE TROUGH AS FAR SOUTH AS NORTHWESTERN KANSAS...HOWEVER THE PRESENCE OF AN ELEVATED MIXED LAYER/POTENTIAL CAPPING CONCERNS CAST SOME DOUBT ON COVERAGE. INTENSE HEATING WILL RESULT IN MODERATE/STRONG INSTABILITY AND WITH 30-40 KTS OF SHEAR...STORMS THAT DO DEVELOP WOULD CARRY SOME RISK OF MAINLY DAMAGING WINDS. THUNDERSTORM COVERAGE MAY INCREASE SOMEWHAT MONDAY EVENING AS A NOCTURNALLY STRENGTHENING LOW-LEVEL JET RESULTS IN STRONG WARM ADVECTION ACROSS THE CENTRAL/NORTHERN PLAINS...AND AN IMPULSE WITHIN SOUTHWEST FLOW ALOFT MOVES ACROSS THE DAKOTAS/WESTERN MINNESOTA. DAMAGING WINDS WOULD BE THE PRIMARY SEVERE THREAT...WITH SOME SEVERE HAIL POSSIBLE. ..BUNTING.. 07/26/2015
from SPC Convective Outlooks http://1.usa.gov/1LHQZVW
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