Get ready for a welcome drop in temperatures, but also gusty winds that will drive high fire danger across northern California through the middle of this week. Low pressure is tracking through the Pacific Northwest Tuesday and will start to dip to the southeast over the next 24 hours. This will result in cooler air funneled into northern California, and will also drive gusty north winds across our region. Multiple Red Flag Warnings have been issued for northern California starting Tuesday and lasting through Wednesday night in some areas. The valley, foothills, and a portion of the Sierra will be under the Red Flag Warning from 5pm Tuesday through 8pm Wednesday. Most of the northern Sierra will be under the Red Flag Warning from 11am through 11pm Tuesday. Trinity County will be under a Red Flag Warning from 1pm Tuesday through 8pm Wednesday, and areas of Modoc and Siskiyou Counties will be under a Red Flag Warning from 2pm through 10pm Tuesday. Gusty north winds and low humidity over dry fuels are the driving factors in our fire danger. Gusts up to around 35mph out of the north will be possible, and humidity will dip into the 10 to 20 percent range this afternoon. Skies are clear this morning, and we'll stay mostly sunny today. Smoke will continue to blanket northern California, but the stronger north winds could help to push much of the smoke impact to our south today. Temperatures are starting out in the 60's to 70's in the valley and foothills this morning, while mountain areas have dipped into the upper 40's to lower 60's early Tuesday. High temperatures are only projected to end up in the low to mid 90's Tuesday afternoon, while mountain and foothill areas range from the upper 70's to upper 80's. Air quality is in the hazardous range in Shasta County, very unhealthy range in Trinity, Plumas, and Lassen Counties, and in the good to unhealthy for sensitive groups range for the mid valley and foothills Tuesday morning. Expect impacts to become more widespread to the south as north winds pick up through the day.
The strongest winds for our valley, foothills, and Northern Mountain areas are expected to occur late Tuesday night through Thursday afternoon. Gusts up to around 35mph out of the north will continue to be possible through Wednesday, and our humidity will dip into the 5 to 20 percent range Wednesday afternoon. Temperatures will start out in the 60's to lower 70's in the valley and foothills, and 40's to 50's in our higher elevations on Wednesday. High temperatures will end up in the low to mid 90's in the valley, and upper 70's to upper 80's in our mountain areas on Wednesday afternoon. This will all be the result of low pressure parked to our northeast keeping our region cooler than average and driving our north winds. Low pressure will exit to the east later this week, and that will result in an uptick in temperatures and lighter winds Thursday and Friday.
The latest models are showing low pressure tracking through the Pacific Northwest this weekend, and that will result in a dip in temperaturs on the way in your weekend forecast. Valley areas are currently projected to top out in the mid to high 80's on Saturday, and low to mid 90's on Sunday. Mountain and foothill areas can expect dry conditions with high temperatures in the 70's to 80's through this weekend. We'll stay dry and get a bit warmer for the start of next week as high pressure builds back into the West Coast.