The transition to an unsettled weather pattern begins today as a slow moving weather system builds in. Here are the overnight forecast updates:

As an unsettled weather pattern builds into NorCal this week, shower and thunderstorm chances are expected.

Shower and isolated thunderstorm chances are beginning to trend a bit more widespread this morning with increasing potential for activity into the Valley and foothills today through Thursday.

As a weather system moves into the region today, isolated thunderstorms will be possible across the mountains and potentially into portions of the Valley this afternoon and evening.

Highest chances for thunderstorms (15-35%) continue to favor the mountains.

โ€ขSlick roads and minor travel delays possible

Chances for high elevation, light snowfall remain persistent this week as well, with best opportunities Wednesday AM and Thursday AM. Forecast snow levels expected to remain 6500′-7500′ or higher.

NWS removed Fire Weather impacts from Wednesday. Gusty north wind potential continues a downward trend and, alongside increasing precipitation chances, attendant fire weather concerns from dry and windy weather are following suit as well.

Probability of rainfall greater than 1 inch

Mountain shower and isolated thunderstorm chances look to linger Friday into the early weekend, although become less widespread as the system gradually begins to depart the region.

A trend toward drier and warmer weather is looking probably through the weekend and into early next week, but confidence remains moderate on this evolving pattern at this time.