January 2, 2018 – Dry today with above average high temperatures. Wet weather returns Wednesday into Saturday. A brief break early next week then potential for more wet weather mid week.
Dry conditions continue with above normal temperatures today as high pressure remains over the west coast. High temperatures today will reach 10 or more degrees above normal. So far, morning fog has been limited and with dew point depressions at generally 2 or more degrees, not expecting significant fog development.
The upper ridge will begin to shift eastward on Wednesday as an upper low currently several hundred miles off the SoCal coast shifts northeastward. A precipitation threat moves into the coast range by Wednesday afternoon as the upper low opens and moves into the northwest corner of the state. The remainder of the north state will see significant cloud cover and nearly all areas will see a few degrees of cooling. Even with this cooling, daytime highs will still come in several degrees above normal.
Precipitation chances spread over the entire forecast area Wednesday night. This relatively weak trough shifts north of the state by mid day Thursday and is not expected to drop heavy precipitation. Snow levels remain generally above pass levels so snow will have minimal impacts on travel.
Thursday will see more cooling with daytime highs coming in just a bit above normal. Another shortwave trough will move northeast across the north state either Thursday night or Friday depending on model. This system will contain a bit more moisture but still not a heavy precipitation producer and with relatively high snow levels should still not produce significantly travel impacts.
Extended discussion (Saturday through Tuesday)
Model forecasts are in better agreement this morning regarding the upper flow pattern this Saturday with a small disturbance moving across northern California with a small stable ridge in place for Sunday. Beyond early Sunday, model solutions diverge between a stormy pattern or a ridge of high pressure for the start of next week.
There are some general similarities for next week, but timing and progression do not line up in model solutions leading to low confidence for next week. At any rate, expect chances for light rain and high elevation light snow for Saturday, and conditions improving for Sunday with continuing chances for light precipitation for the mountains.