SPC 1730Z Day 2 Outlook
DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1230 PM CDT SUN JUL 28 2013 VALID 291200Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SOUTH-CENTRAL PLAINS... ...SYNOPSIS... AN INCREASINGLY LOWER AMPLITUDE/QUASI-ZONAL LARGE SCALE PATTERN WILL EXIST OVER THE CONUS/ADJACENT CANADA ON MONDAY. A CONSEQUENTIAL UPPER TROUGH CURRENTLY OVER THE GREAT LAKES WILL OPEN/BECOME MORE PROGRESSIVE AS IT SPREADS EAST-NORTHEASTWARD TOWARD NEW ENGLAND/SOUTHERN QUEBEC. MEANWHILE...UPPER HEIGHTS WILL SLOWLY BUILD OVER MUCH OF THE ROCKIES/PLAINS...WITH THE STRONGER MID/HIGH LEVEL WESTERLIES EXTENDING FROM THE NORTHERN GREAT BASIN/NORTHERN INTERMOUNTAIN REGION TO THE UPPER MIDWEST/GREAT LAKES. ...SOUTH-CENTRAL PLAINS/LOWER MO VALLEY/OZARKS... A LOOSELY ORGANIZED MCS OR AT LEAST CLUSTERS OF TSTMS ARE LIKELY TO BE ONGOING MONDAY MORNING ACROSS PORTIONS OF KS/MO. ASSOCIATED OUTFLOW/DIFFERENTIAL HEATING WILL HELP TO REINFORCE A FRONTAL ZONE ON THE SOUTHERN EDGE OF THIS EARLY DAY ACTIVITY. BACKGROUND FORCING FOR ASCENT WILL BE RELATIVELY WEAK IN THE PRESENCE OF SLIGHT RISING HEIGHT HEIGHTS INTO THE AFTERNOON/EVENING. HOWEVER...A DESTABILIZING AIRMASS ALONG/WSW OF THE EFFECTIVE FRONTAL ZONE AND WEAK WARM/MOIST ADVECTION WILL LIKELY LEAD TO A RENEWED BOUT OF TSTM DEVELOPMENT BY LATE AFTERNOON/EARLY EVENING ACROSS KS/TX PANHANDLE/FAR NORTHERN OK. MODERATE INSTABILITY AND 30-35 KT OF EFFECTIVE SHEAR MAY SUPPORT SOME INITIAL MODE SUPERCELLS ASIDE FROM A PREVALENT MODE OF SEMI-ORGANIZED CLUSTERS. HIGH MOISTURE CONTENT/PRECIPITATION LOADING IN CONJUNCTION WITH POSSIBLE MCS DEVELOPMENT ARE SUGGESTIVE OF WIND GUST POTENTIAL ASIDE FROM SOME SEVERE HAIL AS STORMS SPREAD EAST-SOUTHEASTWARD THROUGH THE EVENING. ...MT/NORTH-CENTRAL HIGH PLAINS... SURFACE COLD FRONT WILL SPREAD EAST-SOUTHWARD ACROSS THE REGION ON MONDAY AS A RELATIVELY STRONG/LOW AMPLITUDE BELT OF WESTERLIES OVERSPREADS THE REGION. A COMBINATION OF NEAR-FRONTAL CONVERGENCE AND POST-FRONTAL UPSLOPE TRAJECTORIES SHOULD LEAD TO INCREASING TSTM DEVELOPMENT BY LATE AFTERNOON ACROSS THE WESTERN DAKOTAS AND CENTRAL/SOUTHEAST MT AND EASTERN WY IN AREAS NEAR/EAST OF THE BIG HORNS. WHILE THE AIRMASS WILL NOT BE PARTICULARLY MOIST/UNSTABLE...STEEP LAPSE RATES AND SUFFICIENT INSTABILITY /500-1000 J PER KG MLCAPE/ WILL EXIST IN THE PRESENCE OF STRONG VERTICAL SHEAR FOR STRONGER/POTENTIALLY SEVERE TSTMS INCLUDING A FEW SUPERCELLS. ISOLATED BOUTS OF SEVERE HAIL WILL LIKELY BE THE PRIMARY HAZARD...ALTHOUGH LOCALLY DAMAGING WINDS WILL BE POSSIBLE AS WELL. ...MAINE/COASTAL NEW ENGLAND... AHEAD OF THE PROGRESSIVE/OPENING UPPER TROUGH AND ALONG/AHEAD OF A FRONTAL SEGMENT...SUFFICIENT DESTABILIZATION MAY OCCUR IN CONJUNCTION WITH STRONG VERTICAL SHEAR FOR A FEW STRONGER/POTENTIALLY SEVERE TSTMS CAPABLE OF HAIL OR WIND DURING THE DAY. ..GUYER.. 07/28/2013
via SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day2otlk_1730.html
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