The SPC is forecasting ...Severe thunderstorms expected over parts of the Mid-Missouri Valley and the Upper Midwest this afternoon and tonight....   Please read the latest public statement about this event.  View What is a Watch? clip.

   SPC AC 170114

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0814 PM CDT MON JUN 16 2014

   VALID 170100Z - 171200Z

   ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF WRN...CENTRAL
   AND ERN IA...EXTREME SERN MN...SWRN WI...AND EXTREME NWRN IL...

   ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK AREA
   FROM THE WRN GREAT LAKES REGION WWD INTO PART OF THE CENTRAL AND NRN
   PLAINS...

   ...SUMMARY...
   SEVERE THUNDERSTORMS CAPABLE OF PRODUCING WIDESPREAD DAMAGING
   WINDS...VERY LARGE HAIL AND A FEW TORNADOES...WILL PERSIST THROUGH
   THIS EVENING ACROSS NORTHEAST NEBRASKA INTO PART OF NORTHERN IOWA
   AND SOUTHERN MINNESOTA.  WIDESPREAD DAMAGING WINDS SHOULD BECOME THE
   PRIMARY THREAT BY LATE EVENING TO EARLY TUESDAY MORNING ACROSS IOWA
   INTO PART OF SOUTHERN WISCONSIN AND NORTHWEST ILLINOIS.  ADDITIONAL
   ISOLATED TO SCATTERED STRONG TO SEVERE STORMS WILL BE POSSIBLE
   THROUGH TONIGHT INTO THE NORTHERN PLAINS

   ...SYNOPSIS...
   LARGE UPPER TROUGH IN THE WRN U.S. WILL BE MAINTAINED AS CLOSED LOW
   WITHIN THIS SYSTEM DEVELOPS SSE TOWARD THE NRN INTERMOUNTAIN WEST
   AND NRN GREAT BASIN.  THIS EVOLUTION WILL RESULT IN GRADUAL HEIGHT
   RISES DOWNSTREAM FROM THE MID MS VALLEY NWWD THROUGH ERN PORTIONS OF
   THE CENTRAL AND NRN PLAINS.  AS THIS OCCURS...A PROGRESSIVE MIDLEVEL
   SHORTWAVE TROUGH IS RESULTING IN DEEP LAYER ASCENT TO SUPPORT
   ONGOING CLUSTERS OF STRONG-SEVERE STORMS IN SERN SD THROUGH SRN MN
   AND NRN IA.  THIS TROUGH WILL TRACK TOWARD THE WRN GREAT LAKES THIS
   FORECAST PERIOD.  

   AT THE SURFACE...A WARM FRONT STRETCHED FROM NRN OH WNWWD THROUGH
   SRN LAKE MICHIGAN TO ALONG THE IL/WI BORDER TO IN VICINITY OF NRN IA
   AND THE MN BORDER WHERE IT IS CONVECTIVELY ENHANCED BY ONGOING
   STORMS.  THIS BOUNDARY THEN CONTINUED TO EXTEND WNWWD THROUGH FAR
   SERN TO SWRN SD...NRN WY TO WRN MT.  A HIGH THETA-E AIR MASS
   EXTENDED FROM SD...NRN AND ERN NEB THROUGH THE MIDWEST AND OH
   VALLEY.

   ...PART OF MID MO VALLEY AND UPPER MS VALLEY TO WRN GREAT LAKES...
   FORCING FOR ASCENT ATTENDANT TO THE PROGRESSIVE SHORTWAVE TROUGH
   TRACKING THROUGH THE UPPER MS VALLEY TO THE WRN GREAT LAKES REGION
   AND A STRENGTHENING SWLY LLJ EXTENDING INTO IA THROUGH TONIGHT...
   WITHIN A VERY MOIST AND VERY STRONG INSTABILITY FROM ERN NEB ACROSS
   IA TO NRN IL WILL MAINTAIN ONGOING SEVERE STORM POTENTIAL.  ALL
   SEVERE HAZARDS REMAIN POSSIBLE YET THIS EVENING FROM NERN NEB
   THROUGH FAR SERN SD...AND INTO NWRN-NRN IA. MEANWHILE...DAMAGING
   WINDS ARE THE PRIMARY THREAT WITH THE CURRENT BOW ECHO TRACKING EWD
   THROUGH SERN MN AND NERN IA.  INCREASING LOW-LEVEL WAA WITHIN THE
   NOSE OF THE STRENGTHENING LLJ INTO IA AND ASCENT WITH THE SHORTWAVE
   TROUGH SUGGESTS THIS INITIAL BOW WILL BE MAINTAINED WITH A POTENTIAL
   ESEWD TURN ALONG THE INSTABILITY GRADIENT THIS EVENING THROUGH SRN
   WI AND INTO NRN IL.  THESE SAME FACTORS /DEEP LAYER ASCENT AND
   LOW-LEVEL WAA/ WILL SUPPORT ADDITIONAL DAMAGING BOW DEVELOPMENT YET
   THIS EVENING THROUGH TONIGHT ACROSS IA.

   ...WRN AND NRN SD/NERN WY/ERN MT/WRN AND CENTRAL ND...
   THE RESIDUAL MODERATE INSTABILITY EXTENDING NWWD INTO THE NRN PLAINS
   AND EFFECTIVE BULK SHEAR EXCEEDING 35-40 KT SUGGESTS ADDITIONAL
   STRONG TO SEVERE STORMS WILL BE POSSIBLE WITH HAIL AND STRONG WIND
   GUSTS BEING THE PRIMARY THREATS.  A TORNADO CANNOT BE RULED OUT. 
   FOR ADDITIONAL SHORT TERM DETAILS...PLEASE REFER TO SPC MESOSCALE
   DISCUSSION #1027.

   ..PETERS.. 06/17/2014

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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z