Another heat wave on tap for North Bay. Here’s how hot it will get and when

The second heat wave to hit the North Bay in three weeks will push temperatures into the 90s and possibly 100s and increase chances for fire spread, according to the National Weather Service.

The high-pressure system responsible for last week’s highs near 110 degrees is returning Wednesday, weather service meteorologist Dylan Flynn said. This round of higher temperatures will not be as intense but will increase the heat risk well into next week.

“We are going to be up in the upper 90s,” said Flynn, who works in the weather service’s Monterey office. “And, to be honest, the latest trends and forecasts have been turning warmer and warmer.

“We could flirt with triple digits and places like Santa Rosa,” he added.

Temperatures will peak Friday, with 97 degrees in Santa Rosa and 93 degrees in Napa. Cloverdale, consistently one of the hottest spots in the North Bay, is set for 101 degrees.

The weather service issued a heat advisory for Thursday and Friday for inland portions of the North Bay.

Meteorologists are uncertain with the forecast, however, because models are showing varying possibilities for highs. Some are indicating hotter temperatures.

“We don't quite know exactly what's going to happen at this point,” Flynn said.

Given the current forecast, officials are predicting a widespread moderate heat risk in interior portions of the North Bay with some spots of major risk. Those who are more sensitive to heat could become ill if they aren’t in air conditioning, aren’t drinking enough water or are working outside too long.

The marine layer is expected to hold together through the heat wave this time, allowing for higher humidity and more onshore winds to curb threats of red flag warnings.

On Thursday and Friday nights, offshore winds with gusts up to 30 mph in higher elevations coupled with the higher overnight temperatures and lower humidity ― especially in the Mayacamas Mountains ― could create volatile conditions.

The weather service has not issued a fire weather watch, but it is possible, Flynn said. Concerns over fire spread will dissipate Saturday morning, when the winds are predicted to slow.

Though inland areas will battle another round of hot days, the coast will again remain cooler, with highs from the 50s to upper-60s. On Friday, the high could reach 70 degrees in Bodega Bay.

You can reach Staff Writer Madison Smalstig at madison.smalstig@pressdemocrat.com. On X (Twitter) @madi.smals.