A Mesodiscussion is issued by the National Weather Service's Storm Prediction Center when there is a chance of a significant weather event impacting an area. These are routinely issued before weather watches or as updated to weather watches.

SPC MD 1394

MD 1394 CONCERNING SEVERE THUNDERSTORM WATCH 440... FOR NORTHERN ILLINOIS...NORTHERN INDIANA AND WEST-CENTRAL OHIO
MD 1394 Image

Mesoscale Discussion 1394
NWS Storm Prediction Center Norman OK
1158 PM CDT Tue Jul 05 2022

Areas affected...Northern Illinois...Northern Indiana and
West-central Ohio

Concerning...Severe Thunderstorm Watch 440...

Valid 060458Z - 060700Z

The severe weather threat for Severe Thunderstorm Watch 440
continues.

SUMMARY...An isolated severe threat will be possible across parts of
northern Illinois and in west-central Ohio, over the next couple of
hours. A marginal severe threat may also develop in parts of
northern Indiana. Due to the marginal nature of the threat, WW 440
will allowed to expire at 05Z.

DISCUSSION...Latest mosaic radar imagery shows a strong line segment
in northern Illinois, with other thunderstorms ongoing from northern
Indiana to central Ohio. The storms are located along the northern
edge of a moderately unstable airmass, with the RAP showing MLCAPE
across this area in the 1500 to 2500 J/kg range. The line of storms
in northern Illinois will likely continue to move eastward, and be
associated with a marginal wind-damage threat. Further to the
east-southeast, the moderate instability combined with adequate
deep-layer shear, may support an marginal wind-damage threat. The
potential for strong wind gusts may be greatest across western and
central Ohio, where surface-based thunderstorms are already ongoing.

..Broyles.. 07/06/2022

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...CLE...ILN...IWX...IND...LOT...DVN...

LAT...LON   41708600 42138846 42108915 41968959 41708976 41328949
            40828737 40368589 39828457 39538362 39558298 39728282
            40118279 40538314 41188454 41708600 

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SPC Center Public Severe Weather Outlook (PWO)

Public Severe Weather Outlook
      
PWO Image
PUBLIC SEVERE WEATHER OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1137 AM CDT TUE JUL 05 2022

...Severe thunderstorms expected over parts of the Mid-Missouri
Valley and Upper Midwest this afternoon and evening...

* LOCATIONS...
  Southeast South Dakota
  Southwest Minnesota
  Northwest Iowa

* HAZARDS...
  Widespread damaging winds, some hurricane force
  Isolated large hail up to baseball size

* SUMMARY...
  A derecho with embedded significant severe wind gusts appears
  probable from central to eastern South Dakota into southwest
  Minnesota and northern Iowa into this evening.

Preparedness actions...

Review your severe weather safety procedures for the possibility
of dangerous weather today. Stay tuned to NOAA Weather Radio,
weather.gov, or other media for watches and warnings. A watch
means that conditions are favorable for severe thunderstorms
over the next several hours. If a severe thunderstorm warning is
issued for your area, move to a place of safety, ideally in an 
interior room on the lowest floor of a sturdy building.

&&

..Grams.. 07/05/2022

$$

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