As firefighters struggle to gain control of massive wildfires burning across the state, the weather is not doing them any favors.

Fire danger on Wednesday is rated as severe, according to the Wildland Fire Assessment System.

The severe rating stretches from Napa Valley and the Bay Area into Solano and Yolo counties and south to areas like Stockton and Tracy.

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Zoom into the map below to find the fire risk in your area

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Another Red Flag Warning is in effect from 11 AM Wednesday until Thursday at 5 PM.

“Conditions are going to be dry. Winds are going to be gusty. So, it’s the perfect combination for more fires to start up,” says ABC 10’s Michelle Apon.

Weather forecasts call for very low humidity and winds at 10-25 MPH-- with gusts up to 40 MPH. The winds are also going to shift from the southwest to the northwest.

The conditions mean that fires could spread rapidly and there is increased risk of new fires.

Air quality is also a concern for Northern California, with large areas considered unhealthy. That includes areas near the wildfires in Napa and Sonoma counties, as well as near fires in Grass Valley.

Parts of Sacramento also have unhealthy air quality as smoke has become trapped in the valley.

Read more about smoke in Sacramento area

The unhealthy air quality means people with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion. Everyone else should reduce prolonged or heavy exertion.