RED FLAG WARNING. WINDS, DRY CONDITIONS PEAK OVERNIGHT SAT-SUN.

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A strong offshore wind event will take place across most of Northern California from late Saturday through midday Sunday. By midday Saturday strong winds were already building across the peaks of NorCal, including here in the North Bay. Mt. St Helena had already recorded gusts nearing 60mph, winds which are expected to peak in the early morning hours Sunday.

Although the moisture levels and the energy release component of fuels across most of Northern California are relatively good for this time of year, the dry air and low humidity sweeping into the area with north and northeast winds will quickly dry out fine fuels like grasses, especially in the hills where the Red Flag Warning went into effect Saturday morning.

The RFW will be extended to the valleys of the North Bay and much of the Bay Area Saturday afternoon as strong winds mix to the lower elevations.

The reason for all of this is a strong pressure gradient with an insider slider low pressure center moving into the Great Basin to our east.

High resolution models show winds at around 2500 feet peaking between 9PM Saturday and 7AM Sunday morning as the offshore pressure gradient reaches maximum.

You can see the highest winds in the North Bay mountains, with sustained winds of 35-45mph, and gusts expected to 70mph.

In the valleys, winds will be lighter but some gusty conditions are expected to mix to the surface by early Sunday, possibly reaching 25-30mph in gusts throughout Sunday AM.

And relative humidity levels will plunge on Sunday, into the single digits and teens.