Click-to-scroll-up Image
Skip Navigation Links 
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 is the U.S. Government's official Web portal to all Federal, state and local government Web resources and services.

Mesoscale Discussion 1646
< Previous MD         Next MD >
MD 1646 graphic

   Mesoscale Discussion 1646
   NWS Storm Prediction Center Norman OK
   0545 PM CDT Wed Aug 03 2022

   Areas affected...Portions of southeast Lower Michigan...extreme
   northwest Ohio...much of central Indiana...southern
   Illinois...southeast Missouri

   Concerning...Severe Thunderstorm Watch 514...515...516...

   Valid 032245Z - 040015Z

   The severe weather threat for Severe Thunderstorm Watch 514, 515,
   516 continues.

   SUMMARY...The severe threat continues across Severe Thunderstorm
   Watches 514, 515, and 516. Damaging gusts are the main threat with
   stronger storms embedded in the line. The severe threat is expected
   to gradually wane after sunset. Local WW extensions may be

   DISCUSSION...A loosely organized squall line, extending roughly from
   Detroit, MI to areas south of St. Louis, MO, continues to propagate
   east-southeast amid a very unstable airmass (3000+ J/kg MLCAPE per
   22Z mesoanalysis). In the absence of stronger upper flow, shear and
   deep-layer ascent, the squall line persists eastward by means of
   cold pool propagation into a well-mixed boundary layer (90 F surface
   temperatures overspread by 7 C/km 0-3 km lapse rates). As such,
   damaging gusts will continue to accompany the more pronounced line
   segments where locally stronger cold pool(s) can continue to
   interact with the heated/mixed boundary layer. However, nocturnal
   cooling after sunset should support effective cold pool weakening
   and a waning of the severe threat. Until then, locally stronger
   portions of the squall line may propagate outside of the ongoing WWs
   before sunset, and local watch extensions may be needed.

   ..Squitieri.. 08/03/2022

   ...Please see for graphic product...


   LAT...LON   37459093 38858915 40598602 41678452 42148383 42168333
               41728306 41218331 40648383 39988477 39298579 37918801
               37368960 37459093 

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.
Page last modified: August 04, 2022
Information Quality
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities