February 15, 2018 – Dry and milder weather for the remainder of the week. Breezy north winds today. Next system brings a chance of showers to the mountains on Sunday followed by below average temperatures early next week with a possible widespread freeze.
Lingering snow showers over the mountains have ended and skies have mostly cleared out across interior NorCal as the upper trough has shifted to the southeast. Current temperatures are pretty similar to 24 hours ago across most of the area and range from the upper teens and 20s in the mountains to the mid 30s to lower 40s through much of the Central Valley. The exception is at the north end, and along the western edge, of the Sacramento Valley where developing north winds are resulting in 10-15 degrees milder readings this morning with temperatures in the mid to upper 40s.
Clear skies across the region today under subsidence in the wake of the trough. Breezy northerly winds will spread through the Central Valley with gusts of 20-30 mph possible mainly along the western edge of the Sacramento Valley.
Pressure gradients relax later today, and lighter winds will set the stage for patchy frost Friday morning in the valley from about Sacramento southward. Enough north wind is expected north of Sacramento to limit frost potential for most of the Sacramento Valley.
Dry and milder weather expected to continue into the weekend. A few weak waves move over the eastern Pacific ridge Friday and Saturday bringing some high clouds, but otherwise will have little effect.
The next more significant upstream system is forecast to move through the region on Sunday bringing cooler weather and breezier conditions. Similar to the past several systems, precipitation is expected to be light and mainly limited to the mountains.
Extended discussion (Monday through Thursday)
Extended forecast period consists of high amplitude upper ridging in the EPAC with deep troughing along the West Coast. Troughing digs into the Great Basin Monday ushering significantly colder air into Interior NorCal. Unsettled weather expected Monday with showers possible in the foothills and mountains with snow levels lowering to around 1500 feet Monday. Clearing skies Monday night with much colder AMS in place will result in freezing temperatures Tuesday morning with 20s to low 30s in the Central Valley. Drier weather expected through midweek with continued cold overnight lows and daytime highs climbing from below normal Monday to near normal Thursday.