Monitoring of nocturnal flight calls to study bird migration is widely used in the eastern and central United States, but its application in the West has been limited. To assess the potential for such monitoring in northern California and to compare patterns of migration between sites in California’s Central Valley and nearby locations in the Coast Ranges, we analyzed data on flight calls recorded in April and May 2022 by five automated units. We counted all recorded songbird calls and identified four common migratory western songbirds with distinctive flight calls as our focal species: the Swainson’s Thrush (Catharus ustulatus), Wilson’s Warbler (Cardellina pusilla), Yellow Warbler (Setophaga petechia), and Lazuli Bunting (Passerina amoena). We detected songbird calls at a higher rate at the sites in the Central Valley than at those in the Coast Ranges, found differences by site in the nightly frequency of calls from three of the four focal species, and noted more flight calls from migratory species other than songbirds at the Central Valley sites. BirdCast’s radar estimates of nightly average birds in flight strongly predicted the number of songbird nocturnal flight calls we detected each night.