Southern California’s relationship with rain is a tale of extremes. In a region where dry spells are the norm, the occasional deluge can swiftly transform the landscape, posing danger to its residents. This narrative of unpredictability was underscored by the recent “Stormwatch” events. Despite being the subject of occasional ridicule, it played a crucial role in warning the community about impending severe weather conditions.
Forecasters were sounding the alarm for days regarding a series of life-threatening storms poised to hit Southern California. This winter, already marked by extreme weather, witnessed unprecedented flooding in areas like Ventura and San Diego County. These events are expected to occur once in a millennium.
While some heeded these warnings others remained skeptical. But the reality surpassed even the most dire predictions, with the actual rainfall exceeding initial forecasts and reinforcing the critical nature of these alerts.
Downtown Los Angeles braced for 6.37 inches of rain but was inundated with 8.66 inches over a four-day period. This surpassed more than half of the city’s average annual rainfall. Similar patterns were observed across the region with Long Beach, Santa Clarita, Northridge, and Westlake Village all receiving rainfall that exceeded expectations. Pomona, in particular, saw 9.41 inches of rain, significantly higher than the forecasted 6.67 inches. While Pasadena and Ojai received slightly less than anticipated, the storm still left its mark.
Meteorologists attribute the accuracy of these forecasts to their familiarity with the storm’s configuration and orientation, a scenario rare for Southern California but well within their modeling capabilities. The National Weather Service’s Ryan Kittell explained that when lower-lying cities are expected to receive several inches of rain, the implications—ranging from flooding to landslide risks—are comparably severe, regardless of the slight variations in rainfall amounts.
Predictions for mountain and foothill areas were also remarkably precise, with the Sepulveda Pass, Bel Air, and Cogswell Dam in the San Gabriel Mountains receiving upwards of 13 inches of rain. This exceptional rainfall led to significant damage across the region. It affected homes in the Hollywood Hills, the San Fernando Valley, and the San Gabriel Valley due to mudslides and debris flows. Longtime residents, like Dennis Hacela, expressed concern for their safety in the face of such extreme weather.
The storm’s historic nature was well anticipated by the weather service, warning of the potential for significant mudflows and debris across a wider area than typically affected by Southern California storms. This event starkly contrasted with the reaction to Tropical Storm Hilary’s passage through the region last August, where forecasters faced challenges in predicting the storm’s exact path due to its novelty and the complex topography of Southern California.
This storm, however, presented a scenario familiar to the National Weather Service’s meteorologists, allowing for more precise predictions. The storm’s strength, characterized by a central pressure drop to 978 millibars, and its classification as a “bomb cyclone” due to its rapid intensification, contributed to the severe weather conditions experienced across Northern and Central California. This included hurricane-force winds and significant rainfall.
Such accurate forecasting underscores the vital role that meteorological predictions play in preparing for and mitigating the impacts of severe weather. As Southern California grapples with the realities of climate change and its effect on weather patterns, the importance of heeding these warnings cannot be overstated, both for the immediate safety of its residents and the long-term resilience of the region.