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Extreme Heat Warning


URGENT - WEATHER MESSAGE
National Weather Service Tucson AZ
912 PM MST Thu Aug 21 2025

AZZ501>507-509-221215-
/O.CON.KTWC.XH.W.0006.000000T0000Z-250823T0300Z/
Western Pima County-Tohono O`odham Nation-Upper Santa Cruz River
Valley/Altar Valley-Tucson Metro Area-South Central Pinal County-
Southeast Pinal County-Upper San Pedro River Valley-Upper Gila
River Valley-
Including the cities of Marana, Picacho Peak State Park, Sierra
Vista, Tucson, Oracle, Ajo, Vail, Organ Pipe Cactus N.M., Sells,
Safford, Green Valley, Clifton, Benson, Mammoth, and Nogales
912 PM MST Thu Aug 21 2025

...EXTREME HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM MST FRIDAY...

* WHAT...Dangerously hot conditions with temperatures ranging from
  105 to 110 across much of Pima and southeastern Pinal counties
  leading to Major Heat Risk. In other areas of southeastern
  Arizona, high temperatures will range from 100 to 105 degrees.

* WHERE...South Central Pinal County, Southeast Pinal County, Tohono
  O`odham Nation, Tucson Metro Area, Upper Gila River Valley, Upper
  San Pedro River Valley, Upper Santa Cruz River Valley/Altar
  Valley, and Western Pima County.

* WHEN...Until 8 PM MST Friday.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To reduce risk during outdoor work, the Occupational Safety and
Health Administration recommends scheduling frequent rest breaks in
shaded or air conditioned environments. Anyone overcome by heat
should be moved to a cool and shaded location. Heat stroke is an
emergency! Call 9 1 1.

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when possible
and drink plenty of water.

&&

$$

GEL

U.S. Dept. of Commerce
NOAA National Weather Service
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Silver Spring, MD 20910
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Page last modified: June 2, 2009
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