588
WWUS20 KWNS 161736
SEL8
SPC WW 161736
ILZ000-INZ000-LMZ000-170100-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 518
NWS Storm Prediction Center Norman OK
1235 PM CDT Wed Jul 16 2025

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of
  Northern Illinois
  Far Northwest Indiana
  Lake Michigan

* Effective this Wednesday afternoon and evening from 1235 PM
  until 800 PM CDT.

* Primary threats include...
  Scattered damaging wind gusts to 70 mph possible
  Isolated large hail events to 1 inch in diameter possible
  A tornado or two possible

SUMMARY...Scattered thunderstorms are forecast to develop in a
north-south band and move east across the Watch.  A couple of the
stronger thunderstorms may acquire transient supercell
characteristics.  Scattered damaging gusts are the primary hazard,
but an isolated risk for large hail will accompany the stronger
storms and a tornado cannot be ruled out.

The severe thunderstorm watch area is approximately along and 75
statute miles east and west of a line from 40 miles east northeast
of Rockford IL to 20 miles south southeast of Marseilles IL. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU8).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 517...

AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
24025.

...Smith