Severe storm threat continues… Severe thunderstorm watch #138 in effect until 10pm

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The latest thinking on  Severe Thunderstorm Watch #138 from the Storm Prediction Center

 Mesoscale Discussion 0477
   NWS Storm Prediction Center Norman OK
   0325 PM CDT Mon Apr 10 2017

   Areas affected...Portions of IL...extreme east-central
   MO...IN...southern WI...southwest Lower MI...southern Lake MI...far
   western OH

   Concerning...Severe Thunderstorm Watch 138...

   Valid 102025Z - 102230Z

   The severe weather threat for Severe Thunderstorm Watch 138

   SUMMARY...The risk for severe thunderstorms continues across Watch
   138. An isolated severe risk may extend farther south, though
   additional watch issuance is unlikely.

   DISCUSSION...Isolated to scattered thunderstorms continue to develop
   near a front from far south-central WI southward to west-central IL
   and into east-central MO. The greatest coverage of this activity
   lies within western portions of Watch 138, in proximity to the
   strongest deep ascent, and will continue tracking

   Surface-based convection encountering the strongest buoyancy will
   extend across northern parts of central IL east-northeastward into
   northwest Indiana -- characterized by 1000-2000 J/kg of MLCAPE aided
   by a narrow corridor of dewpoints around 60F ahead of the front
   beneath 8.0-8.5 C/km midlevel lapse rates. Semi-discrete cells
   evolving near and south-southwest of the Peoria area will ingest
   this stronger buoyancy and likely be the most intense across the
   Watch area -- from the general area around Peoria east-northeastward
   toward the Pontiac area and farther east-northeast toward the far
   south suburbs of Chicago and adjacent far northwest Indiana. With
   effective shear around 45-55 kt, supercell structures will remain
   possible. The Lincoln IL VAD wind profile indicates slight veering
   of winds with height above the ground, though with ample low-level
   speed shear, supporting around 200-250 m2/s2 of 0-1-km SRH. An
   isolated tornado could occur with the most intense storms, though
   large hail and damaging winds should be the primary risk. Otherwise,
   the risk for severe hail and locally damaging winds will continue
   spreading across Watch 138, with the severe risk diminishing west of
   the front.

   South of Watch 138 near the front, storm coverage should remain more
   isolated owing to weaker deep ascent, though an isolated severe
   hail/wind risk may evolve from the Saint Louis vicinity into
   southern parts of central IL. Convective coverage is presently
   forecast to remain too limited for additional watch issuance. Also
   south of Watch 138, from east-central IL into central IN, a separate
   quasi-linear band of convection is evolving, and will continue
   developing eastward/northeastward during the next several hours.
   This activity will be supported by gradually moistening inflow
   (surface dewpoints rising into the lower 50s) yielding weak
   buoyancy. Effective shear around 30-45 kt, combined with 30-40 kt of
   flow around 1-2 km above ground, may support semi-organized
   convective structures capable of locally damaging wind gusts. Weak
   buoyancy should minimize severe coverage such that additional watch
   issuance is unlikely.
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