City of Irvine
2020 Local Hazard Mitigation Plan
• 2008 - Heavy rain from thunderstorms was produced by a very cold and unstable storm from the north, causing several debris flows. In the Santiago burn area of eastern Orange County, damage was done to homes and businesses.
Severe Wind There have been several strong wind events recorded in and around Irvine 109 :
• In November 1957, Santa Ana winds exacerbated wildland fires, endangered air traffic, and triggered sandstorms in the Fontana area. • In April 1962, strong Santa Ana winds howled throughout the region, uprooting trees, causing property damage and interrupting power transmission to customers. • In November 1996, Santa Ana winds blew at 35 to 45 miles per hour throughout most of southern California, although winds were recorded close to 100 miles per hour in certain areas. In December 1996, gusts were recorded in Fremont Canyon near Tustin at 111 miles per hour. Injuries were recorded in Huntington Beach when a 60-foot tree was uprooted by the winds and fell on top of people. • In October 1997, a fire caused by scrap metal was carried by 45-mile-per-hour Santa Ana winds throughout the Santa Ana Mountains, causing widespread property damage in eastern Orange County. • In October 1998, a thunderstorm sent destructive winds through Orange County. Trees everywhere were uprooted and blown onto vehicles and buildings. A power outage affected more than 18,000 utility customers across the communities of Los Alamitos, Rossmoor, Cypress, Tustin, Santa Ana, and Garden Grove. • In October 2007, winds up to 85 miles per hour blew through Fremont Canyon near Tustin. These winds caused extensive damage to structures and vehicles. The winds also exacerbated existing wildland fires, causing widespread evacuations and the burning of more than 49,000 acres. • In November 2008, strong Santa Ana winds exacerbated and spread the Freeway Complex Fire, one of the most destructive fires in Southern California history. More than 30,000 acres were burned.
Risk of Future Events
Extreme Heat Extreme heat events occur annually in Irvine a few times each year. All expectations are that the probability they will occur again in the future is highly likely and anticipated to increase in the future. Heavy Rain There is no indication that rainfall or severe rain hazards will abate either in Irvine or the greater region of Southern California in the future. While Irvine may experience prolonged periods of dry or wet years, all expectations are that the probability they will occur again in the future is highly likely and anticipated to increase in the future. Severe Wind Given Irvine’s history of severe wind events, it is very likely that wind events will continue to impact the city. The most probable source of wind events in the future will likely originate from the Santa Ana winds
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