CAWFE simulations of the winds in the vicinity of the ignition of the Napa wildfires (Atlas Fire, Partrick Fire, Nuns Fire, Tubbs Fire, and Pocket Fire) at 8 PM ( ~ 1-2 hr before several ignitions were reported). The underlay shows the first higher resolution map of fire extent at ~ 3 AM from the Visible and Infrared Imaging Radiometer satellite (courtesy of University of Maryland and USDA Forest Service Remote Sensing Applications Center).  The upwind edge of the fires lie near locations with ~70-90 mph near-surface winds. (All times local).
These CAWFE simulations use 4 nested domains. The innermost domain, domain 4, - shown above - has 370 m horizontal grid spacing.