UPDATE: 8:30 p.m. Tuesday
SACRAMENTO, Calif. -- Dangerous north and east winds created critical fire weather, lowering humidity and further drying fuels. Peak wind gusts reached above 45 mph in some places.
These dry winds help promote a flare-up on the Bear Fire which is part of the North Complex burning in Plumas County. This fire was started back in mid-August when Northern California had a historic lightning event. The fire was settling down until Tuesday. Below is a time-lapse of the fire development Tuesday.
The winds pulled the smoke from this fire into the valley creating hazardous air at times.
Winds are expected to calm overnight which will keep some of the poor air in place through at least Wednesday morning. A shift in wind direction Wednesday afternoon will start to move some of the smoke out of the valley.
Labor Day weekend's heatwave led to poor air quality across Northern California, especially as northwesterly winds brought smoke into the Valley from the August Complex fire burning in the Mendocino National Forest. Pollutants settled into the Valley and portions of the Sierra Monday.
Overnight, a dry cold front moved in, picking up winds and leading to strong gusts throughout Tuesday, which will last into Wednesday morning. These winds will carry pollutants in different directions and locations depending on the time of day.
There will be periods of time where we see a lot of pollutants being concentrated in certain areas. We’re seeing the accumulation of pollutants moving from the August Complex Fire through the Valley and into areas of the Foothills. The largest unhealthy air qualities are settling in the Foothills and coastal range/Sierras.
Overall, the strong winds will move in from the northwest, helping to disperse the pollutants. So, instead of having “very unhealthy” air quality to “unhealthy” air quality, we are looking at mostly moderate air quality to “unhealthy for sensitive groups” air quality.
Wednesday morning, as winds slowdown in the Valley through the morning, higher concentrations of smoke and pollutants will create hazy skies and ozone levels are expected to be in the high moderate range.