Extreme Heat Warning

Full Alert Message

URGENT - WEATHER MESSAGE National Weather Service Phoenix AZ 1217 AM MST Tue Mar 17 2026 ...EXTREME HEAT WARNING REMAINS IN EFFECT FROM 11 AM MST /11 AM PDT/ WEDNESDAY TO 8 PM MST /8 PM PDT/ SUNDAY... * WHAT...Dangerously hot conditions. Major Heat Risk. Overexposure can cause heat cramps and heat exhaustion to develop and, without intervention, can lead to heat stroke. * WHERE...Portions of southwest Arizona and southeast and southern California. * WHEN...From 11 AM MST /11 AM PDT/ Wednesday to 8 PM MST /8 PM PDT/ Sunday. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Afternoon temperatures 97 to 109 expected. PRECAUTIONARY/PREPAREDNESS ACTIONS... An Extreme Heat Warning means that a period of very hot temperatures, even by local standards, will occur. Actions should be taken to lessen the impact of the extreme heat. 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. 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. Public cooling shelters are available in some areas. Consult county officials for more details.