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Mesoscale Discussion 991
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   Mesoscale Discussion 0991
   NWS Storm Prediction Center Norman OK
   0527 PM CDT Wed Jun 24 2020

   Areas affected...Portions of eastern Alabama into central and
   southern Georgia...southern South Carolina...far northern Florida

   Concerning...Severe Thunderstorm Watch 300...

   Valid 242227Z - 250000Z

   The severe weather threat for Severe Thunderstorm Watch 300

   SUMMARY...The severe threat continues across parts of Severe
   Thunderstorm Watch 300. Damaging wind gusts appear to be the primary
   threat through the remainder of the afternoon. Some severe threat
   may expand east of WW 300, with convective trends being closely

   DISCUSSION...Relatively vigorous convection has become widespread
   over the past few hours, both in the immediate vicinity of an MCV,
   currently located across southwest AL, and with convective clusters
   in both central/southern GA and central SC. A couple of damaging
   wind gusts have been observed over the past few hours with
   convection across GA. In addition, areas east of Severe Thunderstorm
   Watch 300 across east-central GA into western SC continue to receive
   insolation, with sfc-3km lapse rates exceeding 8 C/km and MLCAPE
   around 1500 J/kg. With observations showing temperatures in the 90s
   and temperature/dewpoint spreads exceeding 20F, efficient
   evaporative cooling with the stronger storms may encourage
   additional damaging gusts, until the airmass across this vicinity is
   convectively overturned. 

   In addition, convective outflow slowly sagging southward across SC
   may provide localized lift for a very brief uptick in convective
   activity. A damaging gust or perhaps a brief tornado cannot be
   completely ruled out if a longer lasting updraft happens to traverse
   this boundary. Nonetheless, the severe threat is expected to be
   brief given onset of nocturnal cooling within the next couple of
   hours, and this is reflected in the latest model guidance.

   ..Squitieri/Edwards.. 06/24/2020

   ...Please see for graphic product...


   LAT...LON   30858679 32148704 32868659 33198417 33978275 33527992
               33077953 32158029 31318123 30608304 30858679 

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