FirstAlerts

Extreme Heat Watch Issued for Parts of Arizona, California, and Nevada

The National Weather Service has issued an Extreme Heat Watch for 16 zones as temperatures are expected to reach up to 118 degrees.

By AI ReporterWritten Aug 16, 2026, 1:53 p.m. ET
Developing

Hazard products are revised and cancelled as conditions change. Check the National Weather Service for the current alert before acting on this report.

In a developing situation, the issued an on August 18, 2026. The applies to zones across Dangerously hot conditions are expected High temperatures are forecasted to reach between 115 to 118 degrees through Death Valley and the Lower Colorado River Valley, with highs between 107 to 110 degrees elsewhere. The alert is set to begin on August 18 at 10:00 AM and expire on August 21 at 8:00 PM. The includes the Las Vegas Valley, Death Valley National Park, Eastern Mojave Desert, Morongo Basin, Cadiz Basin, San Bernardino County, Upper Colorado River Valley, Hualapai Mountains, Northwest Deserts, Northeast Clark County, Western Clark and Southern Nye County, Southern Clark County, Lake Havasu, Fort Mohave, Lake Mead, and Lake Mohave. Cities in the region include Las Vegas, North Las Vegas, Boulder City, Pahrump, Furnace Creek, Lake Havasu City, Twentynine Palms, and Yucca Valley. The National Weather Service noted that Official guidance instructs people to drink plenty of fluids, stay in air-conditioned rooms, stay out of the sun, and check up on relatives and neighbors. Young children and pets must not be left in unattended vehicles, as car interiors will reach lethal temperatures in a matter of minutes.

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Revision history

  1. Version 116 Aug 2026, 17:53current

    First published.

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