Dry weather with sunny days and cool overnight temperatures this week. Valley frost and fog possible. Pattern change possible this weekend into next week.
Discussion
Strong high pressure will remain over the region the next few days. Temperatures will be warming up into the mid 60s over the north end of the valley to the mid to upper 50s further south. Winds today look to be a little bit stronger due to a weak wave dropping down through the Great Basin.
Max gusts generally expected to be around 25 mph over the westside of the valley while max gusts in the mountains around 35 to 45 mph for some of the wind prone areas with some stronger gusts over the peaks along the crest.
Areas of fog are expected this morning mainly over the central part of the valley where some dense fog has a 40-50 percent chance to form from around Marysville southward. Otherwise fair weather is expected.
Little change is expected for Thursday other than lighter winds during the day but winds look like they may stay up enough at night to limit any fog development on Thursday morning.
Friday the ridge will begin to break down as a weak wave drops down from the north over Oregon.
Morning temperature will bottom out around the freezing mark and daytime temperatures will be slightly cooler.
Winds are also expected to shift direction and this may allow for more fog to develop in the central part of the valley for Friday morning compared with Thursday but there is a good chance that frost may offset fog development for a lot of places.
By Saturday a weak mainly dry wave will have passed through the region. While a few showers over the Sierra look possible the system looks mainly dry.
The main change will be in the cooler air the system advects over the region.
Extended Discussion (Sunday through Wednesday)
Troughing will be deepening over the Central and Western US for the start of the extended period. We will be on the edge of this and ensemble cluster analysis still shows some uncertainty with how far west troughing builds and also some uncertainty with timing but does favor some rain and snow for northern California.
Only light showers are expected at this time with Valley QPF less than 0.1 inch and mountain snow around 2 to 5 inches.
Breezy winds and below normal temperatures will accompany this pattern change for the weekend into early next week.