Flash flood warnings affect thousands in Southern California
- A pattern of monsoonal moisture is expected to escalate the chance of thunderstorms across the region.
- Flash flood warnings have been issued for various communities in San Bernardino and Los Angeles counties, affecting approximately 28,000 people.
- Residents are advised to seek higher ground and avoid floodwaters due to the potential hazards associated with these storms.
On July 18, 2025, Southern California, specifically Los Angeles and Ventura counties, faced a significant weather event as a pattern of monsoonal moisture moved in from the east. This influx brought with it an increased likelihood of showers and thunderstorms. The National Weather Service (NWS) reported that high clouds indicating this monsoonal flow were appearing in the region, resulting in a forecast that included a slight chance of thunderstorms. The San Gabriel Mountains were particularly highlighted for potential thunderstorms Thursday afternoon, while the broader Los Angeles and Ventura counties faced similar predictions into Friday morning. In conjunction with these forecasts, the NWS issued several flash flood warnings in advance of the anticipated thunderstorms. Areas affected included the San Bernardino Mountains, encompassing communities like Lake Arrowhead, Blue Jay, and Cedar Glen. These warnings were set to remain in effect until 4 p.m. Additionally, a wider warning covered communities near Lucerne Valley, extending until 4:45 p.m. Notably, the NWS acknowledged that about 28,000 individuals were likely impacted by these advisories. In Los Angeles County, a specific flash flood warning was issued for the San Gabriel Mountains, particularly for areas west of Mount Baldy, lasting until 6 p.m. This warning indicated fewer individuals would be affected compared to the San Bernardino advisories, with an estimate of just over 60 residents. Amidst these warnings, the NWS suggested that individuals in advised areas seek higher ground and avoid floodwaters due to the dangers posed by potential flooding. As the weather temporarily worsened in the area, the NWS also released a special weather statement regarding strong winds, impacting various communities including those near Covina, Glendora, and San Dimas until 4 p.m. Overall, the situation highlighted the precariousness of weather patterns during the summer months in Southern California, reflecting not only the immediate threats of thunderstorms and flooding but also the broader implications of climate variability in the region, which may influence similar weather patterns in the future.