High pressure continues to dominate our forecast over Northern California on Thursday, and the Heat Advisory is set to stay in effect through 8pm. Skies have stayed sunny to mostly sunny, and temperatures are 10 to 15 degrees above average. Valley areas have topped out in the 90's to low triple digits in the valley, foothill areas have ended up in the 80's to 90's, and mountain areas have mostly topped out in the 80's. Winds were out of the North early in the day, but are now out of the Southwest to around 10mph.
We'll finally see an end to this modest heat wave as we head into your Friday. Low pressure will start to track towards our region from the Gulf of Alaska and that will result in a drop in high temperatures by around 10 degrees compared to Thursday and clouds increasing in our Norther zones late in teh day. Valley areas will start out in the 60's and will end up in the low 90's on Friday. Foothill areas will dip into the 50's to low 60's overnight and will end up in the high 70's to low 80's, while the mountain areas start out in the low 50's and ends up in the low 80's. Winds will be out of the South to around 15mph, with gusts to 25mph late in the day. Skies will be sunny to mostly sunny in the valley, foothills, and Sierra, but the Northern Mountains will be partly to mostly cloudy late in the day. The potential for showers will move into the Northern Mountains as early as tomorrow evening.
Showers will start to spread across higher elevations in the Northern portion of our region overnight Friday into Saturday and will then be possible in the valley by Saturday afternoon. We'll also have a decent chance for some thunderstorm activity popping up during the afternoon and evening hours. Gusty winds and hail will be possible in areas impacted by thunderstorms. Rain totals are not expected to be significant. Valley areas are mostly projected to see up to a tenth of an inch, while higher elevations are currently projected to get less than half an inch through the weekend. Temperatures will also be much cooler as we head through your weekend. Valley areas will start out in the 50's to 60's on Saturday and will end up in the mid 70's on Saturday afternoon. Foothill areas will start out in the 50's on Saturday and will end up in the 60's to low 70's, while mountain areas start out in the 40's and end up in the 60's. Snow showers will be possible across the Sierra from Saturday night through early Sunday, and snow levels are projected to dip to as low as 5000'. That could make roads slick and make travel somewhat difficult for the latter part of your weekend. We'll be 5 to 10 degrees cooler than Saturday on Sunday. There will be a decent chance for light showers lingering in the moutains and a slight chance for showers in the valley on Sunday. Thunderstorms will also be possible on Sunday, but do not look as likely as Saturday.
High pressure will be building back into Northern California early to mid week next week, and that will result in clearing skies and a warming trend. Valley areas will be back in the 70's to low 80's on Monday, in the mid 80's to low 90's on Tuesday and in the mid 90's by Wednesday. Foothill areas will be back in the 70's on Monday, 70's to low 80's on Tuesday and mid 80's on Wednesday. Mountain areas can expect high temperatures in the mid to high 60's on Monday, mid 70's on Tuesday and 80's on Wednesday.