Flash Flood — Riverside, California

1998-02-23 to 1998-02-24 · near West Portion, Riverside, California

Wider weather episode

A powerful Pacific storm fed by warmer than normal El Nino conditions in the eastern Pacific, slammed into southern California with strong winds, thunderstorms, and very heavy rain. This was the final in a series of heavy storms which pummelled the region this month. In many areas the ground was nearly saturated and some reservoirs were nearing or exceeding their capacity. The two, to locally five inches of rain which ensued, caused widespread flooding and property damage, prompting the President to declare all four counties Federal Disaster Areas. Strong winds gusting over 40 mph at times felled trees, whose support was weakened in the water-logged soils, which snapped utility lines, resulting in sporadic power outages. Snow levels dropped as low as 1400 feet in the high deserts of San Bernardino County and wind gusts to 60 mph knocked out power to thousands. In the mountains, 1 to 2 feet of heavy, wet snow above 6000 feet, snapped tree branches and power lines. Above 7000 feet, 3 to 4 feet of snow fell. In Laguna Beach, two hillsides gave way, sending a river of mud and water through homes and cars. Two men were killed and at least two others injured, and three hundred homes were damaged, 18 of them seriously. In Apple Valley and Hesperia, flooding caused major damage to scores of homes, while hundreds of homes and businesses in other communities suffered minor damage. In Apple Valley alone, two dozen families were evacuated, and damage to public and private property reached $10 million. Parts of 74 roads had to be closed throughout the Victor Valley. Many roads, rail lines, and bridges were damaged or had to be closed for a time, including I-15 through the Cajon Pass. Dangerous swift-water rescues occurred in Colton, Pedley, Canyon Lake, Redlands, Sun City and San Jacinto. In San Diego County, 200 people were evacuated from three mobile home parks in Oceanside, and portions of Camp Pendleton were flooded, due to the raging Loma Alta Creek. Numerous sink holes developed. One near the I-15 and Balboa Avenue in San Diego, measured 550 feet long, 35 feet wide, and 65 feet deep. The San Diego River at Fashion Valley peaked at 15.1 feet at 4:00 am on the twenty-fourth, which is 3.8 feet above flood stage. For the third time this month, low lying roads, golf courses, and parking facilities were inundated. The persistent wet weather damaged the strawberry crop, assorted winter vegetables, citrus and avocado groves, and hurt the flower industry in San Diego County, but losses to dairymen in San Bernardino and Riverside Counties was staggering. Thousands of cows succumbed to the weather. Some drowned, others died of exhaustion and fatigue from struggling through 3 to 4 feet of mud, and many lost calves. Damage estimates to residences, businesses, property, infrastructure, agriculture, and the cost of emergency services, and for clean-up for all four counties exceeded $100 million. While a large percentage of this figure is attributable to this storm, some portion was the result of previous storms this month. The environment that these storms created, helped facilitate the runoff and subsequent flooding which ensued during this final storm of the month. Toward the end of the storm, a small tornado touched down in Huntington Beach at the Villa Huntington Mobile Estates. A carport and children's playroom was ripped up. Flying debris hit a transformer, knocking out power to 200 homes and a portion of a roof settled atop a tree one quarter mile away. Later that morning a waterspout was sighted off of Mission Beach.

Source: NOAA Storm Events Database, event_id 5631321. Narrative written by the NWS forecast office that issued the report.