If forecasts hold true, Northern California’s wet January came to an end after Thursday’s rain.
A ridge of high pressure is expected to develop over the Pacific Ocean and block any storms from reaching the area, perhaps through the first week of February, according to the National Weather Service.
“It looks dry through the next 10 days,” said Drew Peterson, a meteorologist with the weather service. “Any systems that are coming to the West Coast will be getting deflected to the Pacific Northwest and southern British Columbia.”
The system that moved through overnight Wednesday into Thursday delivered a decent soaking, with rainfall totals generally ranging between one-quarter to one-half inch, with more registered in Lake County. According to the Accuweather monitoring station in Lakeport, just over half an inch fell on Wednesday, with another 0.32 added on Thursday. Around the rest of the region, as of 8 a.m. Thursday, 24-hour rainfall totals include Santa Rosa .70 inches, San Francisco .48 inches, Redwood City .40, San Rafael .39, San Jose .36 inches, Oakland .28 and Concord .20.
In the Sierra Nevada, up to 1.5 feet of snow was reported, according to the National Weather Service in Sacramento, which issued a winter weather warning through 10 a.m. Friday. Thursday night, chain controls were in effect for stretches of Interstate 80, Highway 50 and other roadways, according to the California Highway Patrol.
January has been a wet month for much of the area. As of midnight Wednesday, many cities had already surpassed the monthly average for rainfall, including San Francisco 5.13 inches (112 percent of January average), Oakland 4.54 inches (114 percent) and San Jose 3.06 inches (106 percent).
In contrast, Lake County has fallen short of the historical normal for January. As Thursday’s rain began to wane, Accuweather tallied 4.88 inches at the Lakeport station, well below the 6.74 norm.
Still, precipitation has been a relative constant throughout the month. In the first week of January, a third of an inch fell at lake level. Between January 7-12, a large system dumped 2.74 on Lakeport, more in some areas. Almost an inch was added during bouts of damp weather from January `16 through January 22.
As a result, by Thursday at 11:15 a.m., Clear Lake had cleared 2.90 on the Rumsey Gauge and was approaching 3.00.
The January rainfall was not enough to overcome one of the driest Decembers on record. For the water season, which began Oct. 1, rainfall totals throughout California remain below average.
“January is doing what it can to get us out of this deficit,” Peterson said. “The water year is longer than one month. Hopefully February and March will bring us additional rainfall.”
