An atmospheric river is expected to deliver warm rain to Sacramento and heavy, wet snow to the Sierra on Thursday.
Until then, the weather Wednesday is expected to be cloudy and warm with a high of 62 degrees forecast for Sacramento.
Conditions will be different on Thursday when motorists are likely to be coping with slippery and windy driving conditions during the morning commute. Gusts could reach 28 mph in Sacramento.
The weather system is labeled a Pineapple Express because it will be transporting moisture from waters near Hawaii. The National Weather Service is predicting a half-inch to 1.5 inches of precipitation in the valley.
Up in the high country, driving conditions could be hazardous, especially Thursday afternoon and evening, according to the NWS. Snowfall will probably not be light and fluffy, given the tropical nature of the storm.
Still, totals are expected to be fairly good, ranging from a foot to two feet of snow near passes and up to a foot at the 5,000-feet elevation level. The system is expected to exit on Friday but more rain and snow is predicted for Sunday.
The detailed, 7-day forecast from the NWS for the Sacramento region:
Wednesday: Patchy drizzle before 10am. Areas of dense fog before 10am. Otherwise, mostly cloudy, with a high near 62. South southeast wind 5 to 9 mph.
Tonight: Rain, mainly after 4am. Temperature rising to around 60 by 4am. Light south wind increasing to 10 to 15 mph in the evening. Winds could gust as high as 23 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.
Thursday: Rain. Temperature falling to around 55 by 5pm. South southwest wind 10 to 18 mph, with gusts as high as 28 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Thursday night: Rain likely, then rain and possibly a thunderstorm after 10pm. Low around 43. South southwest wind 9 to 11 mph. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Friday: A 40 percent chance of rain, mainly before 4pm. Partly sunny, with a high near 57. South wind 3 to 8 mph.
Friday night: A 20 percent chance of rain before 10pm. Mostly cloudy, with a low around 40.
Saturday: Partly sunny, with a high near 56.
Saturday night: A chance of rain. Mostly cloudy, with a low around 41.
Sunday: Rain likely. Mostly cloudy, with a high near 57.
Sunday night: Showers likely. Mostly cloudy, with a low around 39. Breezy.
Monday: A slight chance of showers. Mostly sunny, with a high near 57.
Monday night: Partly cloudy, with a low around 36.
Tuesday: Mostly sunny, with a high near 57.