Satellite imagery shows cloud cover increasing across NorCal as the closed low that’s been parked off the coast the past several days opens up and lifts out toward the PacNW. The result has been much milder temperatures across the region early this morning. Current temperatures are running 5-10 degrees warmer compared to 24 hours ago and range from the teens in the mountain valleys to the 40s and lower 50s across the Central Valley and thermal belts.
One more dry day with mild temperatures today as the ridge shifts east. Precip chances return tonight and Thursday as the upper trough and trailing front moves ashore. The front weakens quickly as it moves south as upper trough shears to the north with generally light QPF mainly to the north of I-80. Thus the official forecast continues to lean toward the lower end of QPF forecasts.
Active southern stream with relatively deep moisture, but weak lift, continues Friday into the weekend. Mostly cloudy conditions are expected with only low POPs and light QPF.
Extended discussion (Sunday through Wednesday)
The trend for moisture to be further south early next week continues, with Sunday and Monday looking progressively drier for interior Northern California as upper level ridging develops. With just the northern fringe of moisture over the area at best, have kept a slight chance of light precipitation for the Valley from around Chico southward, and a chance in the foothills and mountains for Sunday, and much of the Valley dry on Monday. If current trends continue, all but the Sierra could end up being dry. Precipitation amounts overall are expected to be minimal. High temperatures are also expected to be quite mild, similar to what the area is seeing in the short term.
The leading of a cold front with the next system currently is expected to move in on Tuesday, with wet weather continuing through Wednesday and into Thursday, and potentially beyond. Models have not been doing well recently in this transitional season, so for now will go with a general unsettled pattern for mid to late next week, with periods of precipitation.