Sudden and intense thundershowers pelted the deserts and mountains of Southern California, Arizona and Nevada on Monday in the wake of an invasion of moist, unstable air from Mexico.
By mid-afternoon rain, lightning and winds gusting to 30 m.p.h. at times were reported from Winkelman, Ariz., where .73 of an inch of rain fell in just 30 minutes, to Mt. Laguna in San Diego County, which received 1.65 inches.
Palomar Mountain reported .75 of an inch by late afternoon, while the mountain community of Julian received .65, and Borrego, in the desert, had .41.
Flash-flood watches were in effect for Los Angeles, San Bernardino, Riverside, San Diego, Kern, Inyo and Imperial counties and for the western parts of Nevada and Arizona. No flash flood watch was called for Orange County, however, said National Weather Service specialist Frankie Shaw, and the two stations in the county that normally report measurable rain, El Toro and Santa Ana, were not in the path of the unstable air and did not receive any moisture.