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 1245
< Previous MD         Next MD >
MD 1245 graphic

   MESOSCALE DISCUSSION 1245
   NWS STORM PREDICTION CENTER NORMAN OK
   0109 PM CDT TUE JUN 30 2015

   AREAS AFFECTED...PORTIONS OF NRN/ERN LA...CNTRL/SRN/WRN MS...FAR SRN
   AR

   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

   VALID 301809Z - 302045Z

   PROBABILITY OF WATCH ISSUANCE...40 PERCENT

   SUMMARY...THE AREA IS BEING MONITORED FOR AN INCREASING RISK OF
   SEVERE THUNDERSTORMS AND POSSIBLE WW ISSUANCE.

   DISCUSSION...AN OUTFLOW BOUNDARY FROM EARLIER CONVECTION ARCS FROM
   FAR SERN AR TO S-CNTRL MS...INTERSECTING A DIFFUSE FRONTAL ZONE
   DRAPED W/E NEAR THE LA/AR BORDER. THE EFFECTIVE TRIPLE POINT IS VERY
   NEAR WEST CARROLL PARISH LA...WHERE ENHANCED MESOSCALE CONVERGENCE
   IS FOSTERING TOWERING CUMULUS. OTHER CUMULUS BUILD-UPS ARE EVIDENT
   NEAR THE FRONTAL ZONE AND ALONG THE OUTFLOW BOUNDARY. THE AIR MASS
   IS BECOMING STRONGLY UNSTABLE IN THE NON-CONVECTIVELY-PERTURBED AIR
   S OF THE FRONTAL ZONE...WITH DIABATIC SFC HEATING AMIDST DEWPOINTS
   IN THE LOWER/MIDDLE 70S SUPPORTING 2500-3500 J/KG OF MLCAPE.
   THUNDERSTORMS WILL LIKELY BLOSSOM ACROSS THE REGION IN THE NEXT FEW
   HOURS -- INITIATING NEAR THE FRONT AND OUTFLOW BOUNDARY -- AND
   BECOME INTENSE OWING TO THE STRONG BUOYANCY. SHV AND JAN VWPS
   SUGGEST THAT THE STRONGER VERTICAL SHEAR IS DISPLACED E OF THE
   STRONGEST BUOYANCY. HOWEVER...THE STRONG BUOYANCY WILL STILL SUPPORT
   INTENSE UPDRAFT MASS FLUXES...WITH CORRESPONDING RISKS FOR DMGG WIND
   GUSTS AND SVR HAIL. THE DMGG-WIND RISK WOULD LOCALLY INCREASE WHERE
   COLD POOLS AMALGAMATE YIELDING UPSCALE CONVECTIVE GROWTH. THIS
   ACTIVITY MAY SPREAD E INTO THE MODIFYING COLD POOL IN MS...WHERE
   DEEP SHEAR WILL BE SLIGHTLY ENHANCED -- PERHAPS FACILITATING MORE
   ORGANIZED/FORWARD-PROPAGATING CONVECTIVE CLUSTERS.

   ..COHEN/HART.. 06/30/2015


   ATTN...WFO...JAN...LIX...LCH...SHV...

   LAT...LON   31959004 31319026 31129118 31289289 32149389 33039367
               33119214 32949090 31959004 

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 30, 2015
Disclaimer
Information Quality
Help
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities