Parts of Sonoma and Napa Counties are under a red flag warning until five p.m. The National Weather Service is calling for low relative humidity, at 25-percent, and winds of 20-miles-per-hour in the North Bay interior mountains. Gusts could be as strong as 30 to 35-miles-per-hour. The same winds creating dangerous fire weather are making for poor air quality as well. Wildfire smoke from Northern California and Oregon has been in the Bay Area since Tuesday.
