Thunderstorms occur several times a year, mostly during the winter months, but are usually quite brief. Total annual precipitation, most of which falls from November to April, ranges from at the nearby National Weather Service station at San Francisco International Airport to over in the higher hills (according to observations by Gayle Rucker for the Army Corps of Engineers and Robert E. Nylund for the U.S. Geological Survey from 1962 to 1985). Nylund also took temperature observations for several years and published weekly weather reports in the "San Bruno Herald" from 1966 to 1969, which were included in official reports for the Golden Gate National Cemetery. The annual average days with measurable precipitation is 65.2 days. The most rainfall in a month at the airport was in February 1998, and the most rainfall in 24 hours was on January 4, 1982. Nylund reported in Crestmoor during a 24-hour period in January 1967. Winter storms are often accompanied by strong southerly winds.