A heat advisory was issued Monday by the National Weather Service, warning of excessive temperatures in the middle of the week that could reach triple digits in interior areas.
The advisory warns of potentially unhealthy conditions, especially for those in vulnerable groups.
The warning is effective from Wednesday morning through Thursday night for counties from Monterey to Mendocino.
The Weather Service recommended avoiding strenuous outdoor activity and shifting necessary activity to earlier or later in the day.
Never leave pets in vehicles, even with windows down.
Coastal highs are forecast to reach into the low 90s. Overnight lows will range from the mid 60s to mid 70s.
Interior areas could see higher temperatures, including highs that reach into the 100s in higher elevations.
The high temperatures could cause heat-related illness in vulnerable populations if precautions are not taken, according to the Weather Service, which urged increased attention to hydration during the advisory.
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