Get ready for a hot start to your work week, and the potential for more mountain thunderstorms on the way for this afternoon and evening. Skies are mostly clear this morning, but a few thin clouds are lingering from the active weather we had on Sunday. Temperatures are starting out very warm, with 60's to 70's in the valley, and 50's to 60's in the mountains. Winds are out of the northeast to around 5mph to start the day, but are expected to shift to become out of the south to around 10mph this afternoon. Gusts to 20mph will be possible in some areas. Humidity has recovered somewhat well overnight and is starting out above 50 percent in most areas, but will dip into the high single digits to around 30 percent this afternoon. High temperatures will continue to end up well above average today. Valley areas are projected to top out in the high 90's to around 108 degrees, while foothill areas end up in the low to mid 90's, and mountain areas climb into the 90's to low triple digits this afternoon. There will be potential for thunderstorm activity in the Sierra and the Northern Mountains later today, and that will increase fire danger in those zones. All around, fire danger will be in the moderate to high range today.
Temperatures will end up several degrees cooler across our region on Tuesday, but the threat of Sierra thunderstorms, gustsy winds, and low humidity will result in a Fire Weather Watch going into effect for portions of the Sierra from Tuesday afternoon through Wednesday evening. Humidity will dip into the teens, winds will be out of the west in the 20 to 30mph range, and thunderstorms could spark new fires. Valley temperatures will start out in the 60's to 70's and end up in the mid 90's to low triple digits on Tuesday. Foothill areas will start out in the 60's to low 70's, and end up in the 80's to low 90's on Tuesday afternoon, and mountain areas will start out in the 50's and end up in the high 80's to mid 90's on Tuesday. Wednesday will be very similar to Tuesday, but the threat of thunderstorms will mostly be off to our east.
High pressure will build back into northern California late this week, and that will result in another upswing in temperatures on the way for your late week and weekend forecast. Valley areas will end up back in the high 90's to around 105 degrees by the end of the week, while foothill and Sierra locations end up in the low to mid 90's. The Northern Mountains will top out in the low 90's to around 100 degrees late this week. Triple digit heat looks likely for the entire valley this weekend, with most areas projected to top out in the 100 to 107 degree range. Foothilll and Sierra locations will end up back in the low to mid 90's both days this weekend, and the Northern Mountains will be in the 90's to low triple digits.