Heat Advisory

Locations Affected

Riverside, CA ∙ San Bernardino, CA ∙ Corona, CA ∙ Fontana, CA ∙ Ontario, CA ∙ Moreno Valley, CA ∙ Rancho Cucamonga, CA ∙ Rialto, CA ∙ Murrieta, CA ∙ Temecula, CA

Full Alert Message

URGENT - WEATHER MESSAGE National Weather Service San Diego CA 1156 AM PDT Tue Aug 18 2026 ...HEAT ADVISORY IN EFFECT FROM 10 AM WEDNESDAY TO 8 PM PDT THURSDAY... * WHAT...Temperatures up to 105 expected. * WHERE...San Bernardino and Riverside County Valleys-The Inland Empire. * WHEN...From 10 AM Wednesday to 8 PM PDT Thursday. * IMPACTS...Hot temperatures may cause heat illnesses. 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.

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