529  
ACUS01 KWNS 241244  
SWODY1  
SPC AC 241242  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0742 AM CDT SUN JUL 24 2016  
 
VALID 241300Z - 251200Z  
 
...THERE IS A MRGL RISK OF SVR TSTMS GREAT LAKES TO CNTRL HIGH  
PLAINS...  
   
..SUMMARY
 
 
ISOLATED SEVERE STORMS WILL BE POSSIBLE ACROSS THE GREAT LAKES AND  
MIDWEST REGIONS...ALONG WITH THE CENTRAL HIGH PLAINS...MAINLY LATE  
AFTERNOON AND EVENING.  
   
..SYNOPSIS
 
 
A SHORTWAVE TROUGH WILL MOVE EAST ACROSS ONTARIO...WITH AN EMBEDDED  
IMPULSE AND ASSOCIATED MID-LEVEL SPEED MAX TRANSLATING THROUGH THE  
BASAL PORTION OF THE TROUGH OVER THE UPPER GREAT LAKES TONIGHT.  
PRIMARY SURFACE CYCLONE SHOULD SHIFT OVER NORTHERN ONTARIO WITH AN  
ATTENDANT COLD FRONT PUSHING EAST ACROSS THE UPPER GREAT LAKES.  
TRAILING PORTION OF THIS BOUNDARY SHOULD STALL AND BISECT KS.  
   
..GREAT LAKES...MIDWEST
 
 
AN MCS IS ONGOING ACROSS CENTRAL LAKE MI INTO WEST-CENTRAL LOWER MI.  
THIS ACTIVITY SHOULD SPREAD EAST-SOUTHEAST ACROSS LOWER MI THIS  
MORNING AMID PERSISTENT LOW-LEVEL WAA. POTENTIAL WILL EXIST FOR  
SURFACE-BASED STORM DEVELOPMENT THIS AFTERNOON ALONG TRAILING  
OUTFLOW WITH A RISK FOR MARGINAL SEVERE WIND/HAIL WITHIN A MODESTLY  
SHEARED ENVIRONMENT.  
 
FARTHER WEST...NEAR-NEUTRAL 500-MB HEIGHT CHANGE AND A NOTABLE DRY  
AIR INTRUSION /PER WATER VAPOR IMAGERY/ OVERSPREADING FROM THE UPPER  
MS VALLEY...SUGGEST THAT SURFACE-BASED STORM DEVELOPMENT ALONG THE  
COLD FRONT SHOULD BE DELAYED AND RATHER ISOLATED THROUGH PEAK  
HEATING. A FEW STORMS MAY FORM LATE DAY OVER EASTERN UPPER MI AS THE  
LEADING EDGE OF MID-LEVEL HEIGHT FALLS/DCVA BEGIN TO OVERSPREAD THE  
FRONT. THE MAIN UNCERTAINTY THIS FAR NORTH IS THE DEGREE OF  
DESTABILIZATION...BUT A SEVERE STORM OR TWO WITH SEVERE HAIL/WIND IS  
POSSIBLE. ANOTHER AREA OF LATE AFTERNOON/EARLY EVENING DEVELOPMENT  
MAY BE ACROSS SOUTHEAST WI/NORTHERN IL WHERE LARGE UNCAPPED BUOYANCY  
SHOULD EXIST BETWEEN THE FRONT AND LAKE MI /PER MODIFIED 12Z DVN  
RAOB/. IF STORMS FORM...MODEST DEEP SHEAR SHOULD YIELD A PREDOMINANT  
CLUSTER MODE AND A RISK FOR SEVERE WIND/HAIL.  
 
GREATER FORCING FOR ASCENT WILL OVERSPREAD THE FRONT/WARM SECTOR  
TONIGHT AS A 60-KT 500-MB SPEED MAX BECOMES CENTERED OVER NORTHERN  
LOWER MI BY EARLY MORNING MONDAY. THIS SHOULD YIELD SCATTERED STORMS  
DEVELOPING ALONG THE FRONT AND RESIDUAL EARLY-DAY OUTFLOW BOUNDARIES  
FROM THE LOWER GREAT LAKES TOWARDS THE MID-MS VALLEY. WHILE TIME OF  
DAY SHOULD LIMIT OVERALL INSTABILITY AND THE BULK OF STRONG  
MID/UPPER-LEVEL FLOW SHOULD LAG BEHIND THE FRONT...MODERATE BUOYANCY  
WITH MODEST DEEP SHEAR COULD SUPPORT AN ISOLATED SEVERE  
WIND/MARGINAL SEVERE HAIL RISK CONTINUING INTO THE OVERNIGHT.  
   
..CENTRAL PLAINS
 
 
THE TRAILING COLD FRONT EXPECTED TO STALL ACROSS KS TODAY WILL  
LARGELY SETTLE SOUTH OF MODERATE MID-LEVEL FLOW WHERE SHEAR WOULD  
SUPPORT ORGANIZED UPDRAFTS. EVEN SO...ROBUST SURFACE HEATING SHOULD  
AID IN WIDELY SCATTERED STORM DEVELOPMENT BY LATE AFTERNOON WITH HOT  
TEMPERATURES SOUTH OF THE FRONT CONDUCIVE TO SPORADIC STRONG TO  
SEVERE GUSTS.  
 
SHEAR PROFILES WILL BE MORE SUPPORTIVE FOR ORGANIZED UPDRAFTS ACROSS  
THE HIGH PLAINS FROM SERN WY INTO CO WHERE VEERING PROFILES WITH  
HEIGHT MAY ENABLE UPDRAFTS TO WEAKLY ROTATE. DIABATIC HEATING  
ACROSS THE HIGH TERRAIN AND WEAK EASTERLY LOW-LEVEL INFLOW COULD  
ENCOURAGE A CLUSTER TO GRADUALLY PROPAGATE SOUTHEAST OVER EASTERN CO  
WITH A RISK FOR ISOLATED SEVERE WIND/HAIL.  
 
..GRAMS/MARSH.. 07/24/2016  
 

 
 
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