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Extreme Heat Watch


URGENT - WEATHER MESSAGE
National Weather Service St Louis MO
203 AM CDT Fri Jun 20 2025

ILZ099>102-MOZ061-063>065-202215-
/O.CON.KLSX.XH.A.0001.250621T1700Z-250625T0200Z/
Jersey IL-Madison IL-Saint Clair IL-Monroe IL-Saint Charles MO-
Saint Louis MO-Saint Louis City MO-Jefferson MO-
Including the cities of Alton, Belleville, Saint Louis, Saint
Charles, Cahokia, and Edwardsville
203 AM CDT Fri Jun 20 2025

...EXTREME HEAT WATCH REMAINS IN EFFECT FROM SATURDAY AFTERNOON
THROUGH TUESDAY EVENING...

* WHAT...Dangerously hot conditions with heat index values up to 109
  possible.

* WHERE...In Illinois, Jersey IL, Madison IL, Monroe IL, and Saint
  Clair IL Counties. In Missouri, Jefferson MO, Saint Charles MO,
  Saint Louis City MO, and Saint Louis MO Counties.

* WHEN...From Saturday afternoon through Tuesday evening.

* IMPACTS...Heat related illnesses increase significantly during
  extreme heat and high humidity events.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors.

Do not leave young children and pets in unattended vehicles. Car
interiors will reach lethal temperatures in a matter of minutes.

Monitor the latest forecasts and warnings for updates.

If you do not have air conditioning in your home or lack shelter,
you can call 211 for assistance locating appropriate shelter from
the heat.

&&

$$

Jaja

U.S. Dept. of Commerce
NOAA National Weather Service
1325 East West Highway
Silver Spring, MD 20910
E-mail: w-nws.webmaster@noaa.gov
Page last modified: June 2, 2009
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