Jul 22, 2014 1300 UTC Day 1 Convective Outlook

DAY 1 CONVECTIVE OUTLOOK  

   NWS STORM PREDICTION CENTER NORMAN OK
   0758 AM CDT TUE JUL 22 2014

   VALID 221300Z - 231200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL PLNS ENE INTO
   LWR MI...

   ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN HIGH PLNS...

   ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF CNTRL ORE...

   ...SUMMARY...
   SCATTERED SEVERE STORMS WITH WIND AND HAIL WILL OCCUR LATER TODAY
   AND TONIGHT FROM THE CENTRAL PLAINS EAST-NORTHEAST TO SOUTHERN LAKE
   MICHIGAN. A CLUSTER OF SEVERE STORMS IS POSSIBLE OVER THE BLACK
   HILLS REGION...AND MORE ISOLATED WIND AND HAIL STORMS MAY OCCUR OVER
   INTERIOR PORTIONS OF THE PACIFIC NORTHWEST.

   ...SYNOPTIC SETUP...
   STRONG SRN RCKYS RIDGE WILL EXPAND N INTO THE NRN HIGH PLNS THIS
   PERIOD AS ITS NERN EXTENSION TEMPORARILY IS NIPPED BY
   CONVECTIVELY-ENHANCED SHORTWAVE TROUGH NOW CROSSING LK SUPERIOR. ON
   THE WRN FLANK OF THE RIDGE...SEASONABLY STRONG SSW FLOW WILL PREVAIL
   OVER THE FAR W. A SHORTWAVE IMPULSE IN THIS JET...NOW OFF THE CNTRL
   CA CST...SHOULD CONTINUE NNE INTO NRN CA THIS EVE. THE SYSTEM SHOULD
   THEN ACCELERATE INTO NRN ID BY 12Z WED AS WINDS FURTHER STRENGTHEN
   AHEAD OF POTENT UPR LOW MOVING SSE OFF THE BC/WA CST. ELSEWHERE...A
   WEAK UPR LOW WILL CONTINUE DRIFTING WSW ALONG THE CNTRL GULF CST.

   AT THE SFC...COLD FRONT ASSOCIATED WITH LK SUPERIOR IMPULSE WILL
   ADVANCE STEADILY SE ACROSS THE UPR GRT LKS AND MID MS VLY THROUGH
   TNGT AS ITS WRN PORTION BECOMES STNRY OVER THE CNTRL HIGH PLNS.

   ...CNTRL PLNS ENE INTO IL/IND/SRN WI/LWR MI TODAY/TNGT...
   SEVERAL BANDS OF MODERATE TO STRONG STORMS LIKELY WILL CONTINUE ENE
   ACROSS UPR MI AND PERHAPS NRN LWR MI LATER THIS MORNING THROUGH
   EARLY THIS AFTN ON SRN FRINGE UPR IMPULSE CROSSING CNTRL/SRN ONT.
   WHILE SEASONABLY STRONG/VERTICALLY VEERING FLOW WILL BE SUFFICIENT
   FOR SUPERCELLS...MODEST MOISTURE AND STRENGTHENING EML CAP WILL
   LIMIT BUOYANCY. SFC HEATING AND TRAILING BAND OF MOISTURE ARRIVING
   FROM MN/WI COULD...HOWEVER...YIELD A SOMEWHAT MORE FAVORABLE
   ENVIRONMENT FOR STORMS OVER LWR MI THIS AFTN AND EVE AS A SECONDARY
   WAVE OF ASCENT LOOSELY TIED TO THE DEPARTING ONT TROUGH BRUSHES
   REGION.

   THE SECONDARY WAVE OF ASCENT ALSO COULD SPARK STORMS IN CONSIDERABLY
   MORE UNSTABLE ENVIRONMENT FARTHER SW FROM SRN WI/NRN IL/SE IA INTO
   NRN KS LATER THIS AFTN AND EVE. HEATING IN THIS CORRIDOR WILL BOOST
   SBCAPE TO BETWEEN 3000 AND 5000 J/KG ALONG AND AHEAD OF COLD FRONT.
   N TO NWLY DEEP SHEAR WILL RANGE FROM LESS THAN 20 KTS IN KS TO
   AROUND 35 KTS OVER SRN LK MI. SCTD SVR STORMS CAPABLE OF LARGE HAIL
   AND DMGG WIND THUS APPEAR POSSIBLE AS EML CIN IS BREACHED. THE
   ENVIRONMENT SHOULD BECOME FAVORABLE FOR THE ACTIVITY IN THE MID-MS
   VLY/MIDWEST TO CONSOLIDATE INTO SW-DEVELOPING CLUSTERS LATER THIS
   EVE INTO TNGT...WITH A CONTINUED RISK FOR SVR WIND AND HAIL.

   ...NRN HIGH PLNS THIS AFTN/EVE...
   SFC FLOW WILL VEER TO SELY ON BACKSIDE OF POST-FRONTAL SFC HIGH
   ENTERING THE NRN PLNS. WEAK UPSLOPE FLOW AND STRONG HEATING WILL
   OCCUR BENEATH COOL MID-LVL TEMPS AND 40 KT WNWLY 500 MB FLOW. WITH
   SUFFICIENT LOW-LVL MOISTURE LIKELY TO REMAIN FOR STORMS...SETUP MAY
   YIELD A FEW SUPERCELLS CAPABLE OF LARGE HAIL...LOCALLY DMGG
   WIND...AND PERHAPS A TORNADO.

   ...NRN CA/ORE/ID/WRN MT/NRN NV THIS AFTN INTO TNGT...
   SUBSTANTIAL DEEP-LAYER SHEAR WILL YIELD LONG HODOGRAPHS TODAY IN 
   STRENGTHENING SSW FLOW DOWNSTREAM FROM CA UPR IMPULSE. IN
   ADDITION...COOL MID-LVL TEMPS AND STRONG HEATING WILL YIELD STEEP
   LOW TO MID-LVL LAPSE RATES...WITH MUCAPE AOA 500 J/KG. THIS SETUP
   COULD SUPPORT SCTD STRONG TO LOCALLY SVR STORMS WITH STRONG TO
   PERHAPS SVR WIND GUSTS AND MARGINALLY SVR HAIL INTO TNGT.