Monsoonal moisture is returning to Southern California, bringing with it a modest but notable chance of thunderstorms for parts of Los Angeles County and the Ventura County mountains, according to the National Weather Service.
Through this Friday, July 19, forecasters are tracking a 15% to 30% probability of monsoonal thunderstorms, primarily impacting mountain regions and the Antelope Valley. The atmospheric setup suggests that if thunderstorms do form, they may lead to localized flash flooding, particularly in elevated terrains, along with the risk of dry lightning—a dangerous fire-starting scenario in parched areas.
The peak window for storm development is Friday afternoon through evening, when daytime heating helps destabilize the atmosphere. The San Gabriel Mountains, Ventura County ranges, and the Antelope Valley are expected to be the most affected. However, there is also a slight risk of storms drifting into the adjacent foothill communities, especially as convection spreads later in the day.
Saturday, a lone thunderstorm may still form over the eastern Los Angeles County mountains, but most of the region will remain dry, with temperatures hovering near seasonal averages, in the mid to upper 80s °F (29–32 °C).
Sunday continues this drying trend, with even slimmer chances of storms and continued mild summer conditions across Southern California.
