December 31, 2017 – Dry weather through the rest of the year with above average high temperatures and patchy morning fog. Chance of seeing some rain by the middle of next week.
Satellite imagery shows a plentiful amount of high clouds moving over the area early this morning. Current temperatures are pretty similar to readings from 24 hours ago and generally range from the mid 20s to lower 30s in the mountain valleys to the mid 30s to lower 40s in the Central Valley with 40s to mid 50s in the foothill and Sierra thermal belts. Some patches of valley fog will be possible again this morning.
Overall, little change is expected thru the first couple of days of 2018 as high pressure remains over the area maintaining the dry and relatively mild weather pattern. Mid-level moisture increases over the region this afternoon into this evening as a wave moves through the ridge. Some virga will be possible with perhaps some sprinkles over the mountains.
Precipitation prospects will increase across NorCal by mid-week as the another batch of energy lifts out of the trough off the West Coast giving the region a glancing blow. QPF is forecast to be relatively low despite decent available moisture (TPW plume around an inch) as stronger forcing goes to our north. Snow levels will also remain high (above 7500 feet).
Extended discussion (Thursday through Sunday)
Wet weather pattern continues through Thursday as shortwave passes through area. Precipitation should decrease later in the day and into the evening as this system exits. Snow levels with this mild system are expected to be above pass levels, so light snow accumulation’s should be mainly over higher peaks. Another mild system moves in on Friday, bringing additional precipitation to the area. Additional weak disturbances could continue chances of precipitation into Saturday, with lingering light precip mainly in the mountains into Sunday. Models seem to be trending a bit drier for early next week.