Southern California Braces for Winter Storm: Flooding Risks Loom Near Burn Scars

As Southern California braces for its first significant rainstorm of the winter, residents, especially those living near recently burned areas, are being urged to prepare for potential flooding and debris flows. The National Weather Service has identified a 10% to 20% chance of flash flooding and debris flow affecting vulnerable regions, particularly those scarred by wildfires. Meteorologist Ryan Kittell from the National Weather Service office in Oxnard emphasizes the importance of readiness, stating, "The threat is high enough to prepare for the worst-case scenario." Areas particularly at risk include the burn scars from the Palisades and Franklin fires around Pacific Palisades and Malibu, the Eaton fire near Altadena and Pasadena, the Hughes fire around Lake Castaic, and the Bridge fire in the Angeles National Forest, which devastated over 56,000 acres last autumn. The recent wildfires have left behind burn scars that significantly increase the risk of flooding because the intense heat makes the soil repellent to water. As rain falls, water tends to flow over the surface rather than being absorbed, leading to potentially hazardous mudflows and debris flows. Although the weather service has indicated that damaging debris flows are not the most likely outcome, the uncertainty surrounding the storm necessitates caution. Kittell advised that while minor impacts are more probable, it’s crucial to remain vigilant as conditions could change rapidly. The flood watch has been issued for a critical period between Sunday afternoon and Monday afternoon, with particular concern for Sunday night when rainfall intensity is expected to peak. During this time, residents are advised to avoid recently burned areas, use sandbags to protect their properties, and stock up on supplies in case access to roads becomes compromised. Rainfall projections have been adjusted upwards, with forecasts indicating that some areas could receive between 1 to 2 inches, particularly in the mountains of Los Angeles and Ventura counties. The anticipated storm, moving slowly from the north, is expected to last throughout the weekend into Monday, bringing a mix of light rain and intermittent heavier showers. Given the severity of the ongoing drought, with most areas receiving less than 5% of the average rainfall since the start of the water year on October 1, this storm could mark a significant change in conditions, even though it may not entirely alleviate drought concerns. Additionally, meteorologists are monitoring a potential for thunderstorms, which could lead to localized heavy rainfall rates. Such conditions could be critical as just half an inch of rain per hour is enough to trigger debris flows in recently burned regions. While the primary expectation is for benign rain across the region, isolated areas may experience intense downpours that could compound the risks of flooding and landslides. As the rain approaches, forecasters are also keeping an eye on high winds, with peak gusts expected to reach up to 60 mph in certain areas, potentially leading to hazardous driving conditions and power outages. Snow levels are predicted to drop, bringing significant snowfall to the mountains, which will contribute to travel difficulties and road closures. In summary, as Los Angeles prepares for the impending storm, the combination of recent wildfire damage, expected rainfall, and the ongoing drought creates a precarious situation. Residents are encouraged to take preventive measures, stay informed, and prepare for potential disruption as the region navigates this challenging weather event.