Sonoma County to face ‘substantial’ rain, subfreezing temperatures this week

The North Bay could experience “substantial” rainfall, subfreezing temperatures and winds up to 40 mph this week, according to the National Weather Service.

Tuesday morning in Sonoma County will begin with temperatures as low as 30 degrees in the interior valleys and 40 in the coastal regions, according to meteorologist Sarah McCorkle of the weather service’s Monterey office.

Wednesday morning is expected to be this week’s coldest period, with lows ranging from the upper 20s to lower 40s. In Santa Rosa, the temperature could drop to 29 degrees.

There is also a 70% to 90% chance of frost on Tuesday and Wednesday mornings and about a 40% to 50% chance of a freeze. Friday and Saturday morning are also predicted to hit subfreezing temperatures.

The temperatures on Tuesday and Wednesday are about 5 to 12 degrees below normal for this time of year, McCorkle said.

“We would expect temperatures to be coldest around this time,” she said, “but given that it is 10 degrees below normal, we do have concerns for those who are unhoused and more vulnerable populations.”

In response to the weather conditions, Santa Rosa announced Monday night it would work with Catholic Charities of the Diocese of Santa Rosa to open a “temporary drop-in warming center.”

It’ll be open 7 p.m. to 7 a.m. Tuesday through Thursday at the Homeless Services Center of Catholic Charities’ Caritas Center, 301 Sixth St., Suite 108.

The entrance is on Morgan and Sixth streets and the facility fits up to 78 people but an outdoor courtyard with heaters will also be used, if necessary.

McCorkle encouraged Sonoma County residents to check on anyone during the coming days who does not have access to heat.

Highs across Sonoma County will also be lower than normal, starting in the upper 50s and lower 60s on Tuesday. Temps will continue to drop until Thursday, when they are expected to stay in the low- to mid-50s through the weekend.

After 12:01 a.m. Thursday, a moderate to heavy rain will begin in the northern portion of the North Bay and continue throughout the region. It is expected to taper off at about 5 p.m., McCorkle said.

Strong winds will also accompany the rain, reaching up to 40 mph in Sonoma County’s higher terrains and up to 25 mph in the valleys.

During the storm, Sonoma County residents could face hazards such as water pooling on roadways, flying debris, flooding in poor drainage areas, overflowing of small streams and possible power outages, McCorkle said.

The coastal mountain ranges are expected to receive about 2 to 3 inches of rainfall and the inland areas, such as Santa Rosa, are predicted to get about 1 to 2 inches.

McCorkle said the rain will be a welcome occurrence following a few weeks without much rainfall in the region.

“Usually this is when we start to see our rain,” she said. “So, we are excited to see it.”

There is also a chance of rain Saturday morning through Sunday afternoon, though the weather service is less sure of timing and rainfall totals for these predicted showers.

As of Monday, mountainous areas in Sonoma County were expected to receive as much as 1½ inches of rain while the lower terrain could get about 1 inch through the weekend, McCorkle said.

Staff Writer Colin Atagi contributed to this report.

You can reach Staff Writer Madison Smalstig at madison.smalstig@pressdemocrat.com. Her Twitter is madi.smals.