Unsettled today, dry Thursday and Friday before the next wave of rain and snow

January 9, 2019 – Unsettled weather will continue today but will be followed by a brief period of dry weather for Thursday. Wet weather will be possible for the weekend and into early next week.

Discussion

Front continues to drop southward through the region early this morning. Winds, while remaining somewhat breezy across much of the area, have decreased behind the front and the wind advisory has been dropped.

Precipitation has picked up across the northern Sierra overnight and Caltrans traffic cameras indicate deteriorating conditions across Donner Pass. Current temperatures remain very mild and range from the 30s in the mountains to the 50s across the Central Valley.

Showery weather continues across the region today in the post- frontal environment. Snow levels will lower to around 5500-6500 feet, and significant snowfall accumulations will be likely across the northern Sierra through this evening. Ridging returns tonight with most of the forecast area expected to dry out. Some patchy morning valley fog will be possible early Thursday.

Dry weather expected Thursday and Friday as the next system is forecast to dig southeast off the coast and head toward SoCal. The western portions of the forecast area may see some showers by later Friday into Saturday as the system skirts by to our west, but confidence is low as to how far inland it could spread.

Extended Discussion (Sunday through Wednesday)

Extended period starts out with frontal band pushing on to the central California coast. Extended models still not consistent in how far associated upper low will dig southward so precipitation amounts in question with ECMWF and its southerly track bringing much less precipitation. Even wetter model keeps precipitation limited but snow levels remain below pass levels so at least some minor mountain travel impacts are expected. Showers continue on Monday as upper low pushes in somewhere along the coast but precipitation amounts remain relatively low so impacts remain minimal. Daytime highs early next week should come in around normal with cloud cover keeping overnight lows above normal.

Next Pacific storm forecast to push into NorCal next Tuesday and Wednesday. More northerly track of this system should ensure higher precipitation amounts across the CWA but timing varies a bit on when this system will move in. Showers round out the extended period Wednesday before possible brief dry out period for the end of next week.