The National Weather Service in Sacramento alerts that the region is bracing for a dynamic weather pattern, beginning today and extending into next week, with multiple weather systems expected to bring rain, wind, and snow to northern California. Morning fog, which could see visibility drop below 0.5 miles, will give way to rain and snow as a series of fronts move through the area, as reported by the National Weather Service.
According to the National Weather Service forecast, rain will start later this morning, transitioning to showers in the Sierra and adjacent foothills by this evening. Rain totals will vary, ranging from 0.25-0.75 inches north of I-80 in the Valley to 0.75-1.50 inches in the foothills and mountain areas. Snow levels starting at 6000-7000 feet are predicted to rise to 7000-8500 feet by the afternoon. Lassen National Park could see up to six to eight inches of snow as the first weather wave progresses.
On Sunday, forecast models show some uncertainty with the timing of the next wave of precipitation, but minor impacts are anticipated with a drier system compared to Saturday's. The National Weather Service advisory notes that, "Snow is not expected to accompany this wave as snow levels will be 7500-8500' during the bulk of the expected precipitation."
Looking ahead to Monday afternoon through Tuesday night, which encompasses Christmas Eve, the National Weather Service expects this period to be the wettest, with significant travel impacts from rain and snow. Snow levels will start high but drop significantly by Tuesday evening to 4500-5500 feet. The Sierra could get an additional four to eight inches of snow, with up to a foot along the crest and near Lassen NP. Gusty south winds are also forecasted, "strongest over the northeastern foothills and over the Sierra," potentially creating challenging travel conditions.
The weather on Wednesday, Christmas Day, is forecasted to be calmer, with only light north winds. However, the active weather pattern is set to resume on Thursday, with another system bringing rain and snow chances through Friday. The National Weather Service concludes, "There is still much uncertainty with this later week system, so stay tuned to the forecast for updates as we move through the weekend when ensembles and cluster analysis come into better agreement." Travelers are advised to keep abreast of the latest conditions by checking road conditions at quickmap.dot.ca.gov or by dialing 511.
