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Feb 20, 2018 0700 UTC Day 2 Convective Outlook
Updated: Tue Feb 20 06:27:18 UTC 2018 (Print Version | 20180220 0700Z Day 2 shapefile | 20180220 0700Z Day 2 KML)
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 Forecast Discussion

   SPC AC 200627

   Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1227 AM CST Tue Feb 20 2018

   Valid 211200Z - 221200Z

   ...NO SEVERE THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   Showers and embedded thunderstorms are expected from Texas through
   the lower Mississippi valley to the central Appalachians Wednesday.

   ...Synopsis...

   A broad positive-tilt synoptic trough will persist over the western
   half of the U.S. Wednesday. Several embedded vorticity maxima will
   eject from the Southern Plains through the OH Valley. A cold front
   from the Great Lakes through south TX will continue southeast, but
   may begin to stall from a portion of the lower MS Valley to Deep
   south TX.

   ...Southern TX through the Lower Mississippi Valley...

   A moist boundary layer with upper 60s F dewpoints will reside in
   pre-frontal warm sector across south and southeast TX supporting
   moderate instability (1000-1500 J/kg MLCAPE). Tendency will be for
   low-level jet to shift northeast away from TX warm sector leaving
   modest flow in the near-surface to 800 mb layer. In south TX the
   east-west orientation of the cold front relative to southwesterly
   winds aloft will contribute to an anafrontal regime where storms
   initiating along the front will tend to become elevated as they
   cross into the cool side of the boundary. Nevertheless MUCAPE from
   400-800 J/kg and 45+ kt effective bulk shear could support some
   threat for hail. Farther east from southeast TX through the lower MS
   valley, stronger winds aloft will reside in post frontal zone with
   modest deep layer and low-level shear in warm sector. Any storms
   developing along warm conveyor belt should remain in an environment
   marginally supportive of storm organization. Due to the potential
   limiting factors, will not introduce severe probabilities this
   update, but a marginal risk category might be needed for a portion
   of these areas in future outlooks.

   ..Dial.. 02/20/2018

   CLICK TO GET WUUS02 PTSDY2 PRODUCT

   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z

        
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Page last modified: February 20, 2018
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