'Eye-witness Accounts of Several Major earthquakes' by Thomas Gold, 1987, includes this description of earthquake lights in Sonoma County. I think the location was 45 or 50 miles NW of Napa. (Dr. Gold is Professor emeritus of Astronomy at Cornell University and for 20 years was Director of Cornell Center for Radiophysics and Space Research).

> While investigating the natural phenomena of the seismic disturbance
> of April 18, 1906, I visited the mountain ranch of Mr. and Mrs. Adams,
> a mile and one-half northeast of Cazadero. They stated that for two night
> preceding the earthquake they "had seen small streams of lightning running
> along the ground". Their attention was called to the phenomenon by the
> incessant barking of their dog.
> Here, evidently some 30 hours before the shock, earthquake lights were
> reported in what was soon to be the epicentral region.

• earthquake lights in Sonoma County 1906