(FOX40.COM) — On Wednesday morning, the Sacramento National Weather Service station expanded the area of concern for Wednesday’s red flag warning.

The area of concern has now moved further east into the Sacramento Valley as well as further south in Solano County and into Sonoma County.

The entirety of Yolo County and parts of Sutter County and Butte County are now included in the red flag warning. The area of concern now extends along the western border of Sacramento County.

The counties under the red flag warning include Butte, Colusa, Glenn, Lake, Napa, Shasta, Solano, Sonoma, Sutter, Tehama and Yolo.

Wind speeds and humidity levels have not changed since the NWS initially called for the red flag warning on Tuesday. The warning is also still expected to expire at 8 p.m. on Wednesday.

Those within the red flag warning area are advised to use caution when operating outdoor equipment and to keep vehicles off of dry grass.

This is the first red flag warning NWS Sacramento has issued in 2023 and the first time since 2011 that a red flag warning has not been issued prior to the month of August.