Showers and thunderstorms expected today with snow continuing in the mountains. Drier weather expected Thursday and Friday. Precipitation chances return over the weekend and persist into next week.
Discussion
The large cold low pressure system continues to spin off the northwest coast of California. Radar shows numerous showers rotating onshore across much of interior NorCal, especially to the north of Interstate 80. QPF has been much lighter overnight compared to Tuesday with amounts generally less than a third of an inch since Tuesday evening.
Interstate 5 north of Redding has reopened as has Interstate 80 over Donner Pass. The low will remain just off the coast as it moves southeast today, reaching the central coast of California by late this evening.
Several bands of showers are will to rotate through the region today with thunderstorm chances forecast to be the greatest from about I-80 southward. Heavy rain, small hail and gusty winds are expected to be the primary threat. Stronger storms may be accompanied by rainfall rates between 1/2 and 1 inch per hour and may lead to some local flooding during the afternoon into the early evening.
Showers will taper off from the north tonight as the low shifts further south. Besides some lingering light snow showers in the mountains, expect mostly dry conditions Thursday as we’ll be under mostly dry northwest flow.
Brief, short-wave ridge will develop Friday keeping drier weather in the forecast. Below normal temperatures will continue with Valley high temperatures in the upper 50’s to near 60 degrees.
The next system moves into far northern California Saturday bringing a return of precipitation to the northern Sacramento Valley and northern mountains, but impacts will likely be considerably less than the current storm.
Extended Discussion (Sunday through Wednesday)
Upper troughing drops into the area Sunday into early Monday bringing a threat of showers with snow showers in the mountains. Highest QPF expected over the northern and eastern foothills/mountains.
Another short wave trough possible Tuesday into Wednesday, however not all models are showing this which is resulting in forecast uncertainty.
Below normal temperatures expected through the extended forecast period.