California Heat Wave Threatens to Break March Temperature Records

Forecasters predict temperatures could reach over 110 degrees in some areas, far exceeding typical March highs.

Mar. 17, 2026 at 12:08am by Ben Kaplan

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Forecasters expect California's ongoing heat wave to shatter temperature records this week, with the Coachella Valley and Imperial Valley potentially reaching highs well above 100 degrees. Experts warn this early-season heat could be especially dangerous, as people's bodies have not yet adapted to the extreme temperatures.

Why it matters

This heat wave is arriving much earlier than normal, raising concerns about public health impacts before people have had a chance to acclimate. It also highlights the growing threat of climate change, with extreme weather events becoming more frequent and severe.

The details

The National Weather Service predicts the community of Thermal could reach 111 degrees on Thursday, which would surpass the current California record for the hottest March day of 107 degrees set in Mecca in 2004. Nationwide, the hottest March temperature on record is a tie between 108 degrees in Rio Grande City, Texas in 1954 and Falcon Dam, Texas in 2020.

  • The heat wave is expected to last from Tuesday through Friday this week.
  • Pinnacles National Park could see its earliest 100-degree day on record, beating the previous record of April 8, 1989.

The players

Rose Schoenfeld

A National Weather Service meteorologist in Los Angeles.

Joe Merchant

A meteorologist for the National Weather Service covering the greater San Francisco Bay Area.

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What they’re saying

“This first heat wave of the season is much earlier than normal. Science shows that your body's adaptation to heat is a big factor in whether or not you see health impacts. We're not adjusted to heat right now in the area, so what normally would be just a regular day could be much more significant.”

— Rose Schoenfeld, National Weather Service meteorologist (SFGATE)

“Virtually every site that we maintain a long record for has a risk of having their record broken. There will be a slew of daily records broken and probably a lot of March records broken, too.”

— Joe Merchant, National Weather Service meteorologist (SFGATE)

What’s next

Meteorologists will continue to monitor the heat wave and provide updates on any new record-breaking temperatures or public health advisories.

The takeaway

This extreme early-season heat wave underscores the growing threat of climate change, with California facing increasingly severe and unpredictable weather patterns that pose risks to public health and safety. Experts warn that communities must take proactive steps to prepare for and adapt to these climate impacts.