Skip Navigation Links weather.gov 
NOAA logo-Select to go to the NOAA homepage NOAA's National Weather Service   Select to go to the NWS homepage
Storm Prediction Center
navigation bar left  
  navigation bar end cap


 
USA.gov is the U.S. Government's official Web portal to all Federal, state and local government Web resources and services.

Mesoscale Discussion 1104
< Previous MD         Next MD >
MD 1104 graphic

   MESOSCALE DISCUSSION 1104
   NWS STORM PREDICTION CENTER NORMAN OK
   0228 PM CDT SUN JUN 21 2015

   AREAS AFFECTED...EASTERN MONTANA AND FAR WESTERN NORTH DAKOTA

   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

   VALID 211928Z - 212130Z

   PROBABILITY OF WATCH ISSUANCE...80 PERCENT

   SUMMARY...A GRADUAL INCREASE IN THUNDERSTORM INTENSITY AND COVERAGE
   IS EXPECTED ACROSS THE DISCUSSION AREA THIS AFTERNOON.  A WW WILL BE
   ISSUED BY 21Z.

   DISCUSSION...A FEW THUNDERSTORMS HAVE DEVELOPED IN NORTHEASTERN
   MONTANA OVER THE PAST 1-2 HOURS...WITH ADDITIONAL DEVELOPMENT LIKELY
   TO OCCUR THROUGH THE LATE AFTERNOON AS INSOLATION/INCREASING
   INSTABILITY AND INCREASING FORCING FOR ASCENT CONTINUE TO OVERSPREAD
   THE DISCUSSION AREA.  CURRENT OBSERVATIONS AND MODEL FORECAST
   SOUNDINGS INDICATE THAT MARGINALLY SEVERE HAIL AND DAMAGING WIND
   GUSTS WILL BE THE MOST LIKELY THREATS WITH THESE STORMS GIVEN
   500-1000 J/KG MLCAPE...20-30 F DEWPOINT DEPRESSIONS...AND 40-50 KNOT
   DEEP LAYER SHEAR.

   LATEST HIGH RESOLUTION MODEL GUIDANCE INDICATES POTENTIAL FOR A FEW
   SUPERCELLS OVER SOUTHEASTERN MONTANA AND SOUTHWESTERN NORTH DAKOTA
   TOWARD EVENING.  A BRIEF WINDOW OF HEIGHTENED TORNADO THREAT MAY
   EXIST ACROSS THESE AREAS AS STORMS MOVE INTO AN ENVIRONMENT WITH
   HIGHER BOUNDARY LAYER MOISTURE/LOWER LCLS AND A STRENGTHENING
   LOW-LEVEL JET.  THIS THREAT WILL BE CONDITIONAL UPON STORMS
   REMAINING AT LEAST SEMI-DISCRETE DURING THAT TIME FRAME...WITH THE
   LIKELIHOOD OF STORMS CONGEALING INTO A COMPLEX INCREASING WITH
   TIME...ESPECIALLY AFTER DARK.

   A WW WILL BE ISSUED BY 21Z.

   ..COOK/CARBIN.. 06/21/2015


   ATTN...WFO...BIS...UNR...BYZ...GGW...TFX...

   LAT...LON   47460868 47740821 47970741 48680643 48950563 48990496
               49000388 48980292 48840249 48480208 47860192 47190194
               46700224 46100287 45770359 45570456 45460570 45510686
               45810785 46400876 46830899 47110895 47460868 

Top/All Mesoscale Discussions/Forecast Products/Home
Weather Topics:
Watches, Mesoscale Discussions, Outlooks, Fire Weather, All Products, Contact Us

NOAA / National Weather Service
National Centers for Environmental Prediction
Storm Prediction Center
120 David L. Boren Blvd.
Norman, OK 73072 U.S.A.
spc.feedback@noaa.gov
Page last modified: June 21, 2015
Disclaimer
Information Quality
Help
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities