MESOSCALE DISCUSSION 1211
   NWS STORM PREDICTION CENTER NORMAN OK
   0908 AM CDT MON JUN 30 2014

   AREAS AFFECTED...PORTIONS OF ERN NEB INTO SWRN IA

   CONCERNING...SEVERE THUNDERSTORM WATCH 372...

   VALID 301408Z - 301515Z

   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 372
   CONTINUES.

   SUMMARY...PARTS OF WW 372 IN ERN NEB INTO SWRN IA MAY NEED TO BE
   UPGRADED TO A TORNADO WATCH.  CURRENT THINKING AT SPC INDICATED
   CONCERN FOR A POTENTIAL INCREASE IN THE TORNADO THREAT THROUGH THE
   MORNING ACROSS THIS DISCUSSION AREA.

   DISCUSSION...MID-MORNING SURFACE ANALYSIS PER TRENDS IN OBSERVATIONS
   AND VISIBLE SATELLITE/RADAR IMAGERY SHOWED AN OUTFLOW BOUNDARY
   ARCING ACROSS FAR SRN IA /FROM SRN WASHINGTON COUNTY TO LUCAS
   COUNTY...AND THEN NWWD TO POTTAWATTAMIE COUNTY NEAR THE STORM THAT
   PRODUCED GOLF BALL SIZE HAIL AT 1306Z/.  MEANWHILE...AN AREA OF LOW
   PRESSURE WAS LOCATED NEAR BBW WITH A WARM FRONT EXTENDING EWD TO
   NEAR OMA.  THESE TWO BOUNDARIES ARE LOCATED WITHIN A W-E CORRIDOR OF
   VERY RICH MOISTURE /SURFACE DEWPOINTS IN THE LOWER 70S/...VERY
   STRONG INSTABILITY AND A VORTICITY RICH ENVIRONMENT.  THE STORM IN
   NERN NEB...NEAR 30 WSW SUX AT 1350Z...APPEARS TO BE LOCATED ALONG A
   WEAK BOUNDARY EXTENDING FROM NEAR OFK NEWD INTO NWRN IA...AND IS
   ASSOCIATED WITH A RELATIVELY COOLER...MORE STABLE AIR MASS.  

   A MIDLEVEL SHORTWAVE TROUGH CURRENTLY TRACKING THROUGH CENTRAL/SRN
   NEB AND NRN KS WILL SPREAD EWD.  ASCENT WITH THIS FEATURE COMBINED
   WITH A ZONE OF PERSISTENT LOW-LEVEL WAA WITHIN THE NOSE OF A 30 KT
   SSWLY LLJ SUGGESTS STORMS WILL CONTINUE TO DEVELOP OVER ERN NEB INTO
   WRN IA.  AFOREMENTIONED FACTORS COMBINED WITH SFC-1 KM SHEAR OF 30
   KT AND 0-1 KM SRH OF 260 M2/S2 PER OMA WSR-88D SUGGESTS STORMS
   FORMING AND/OR INTERACTING WITH THE WARM FRONT AND IA OUTFLOW WILL
   HAVE A TORNADO POTENTIAL.  LARGE HAIL AND DAMAGING WINDS WILL BE A
   THREAT AS WELL.

   ..PETERS/CORFIDI.. 06/30/2014


   ATTN...WFO...DMX...OAX...

   LAT...LON   41999709 41949642 41739558 41439421 40989399 40849499
               40969618 41009686 41499728 41999709