Overview
- The monsoonal surge is moving into California this weekend, bringing increased mid- and high-level clouds, higher humidity, and the season’s first isolated thunderstorms.
- Many coastal and Bay Area storms are expected to be high‑based and produce virga, which can allow lightning to strike with little wetting rain and thus raise the risk of new fire starts.
- The Sierra Nevada has the best chance for wetting storms, with agencies estimating roughly a 20 to 25 percent thunderstorm probability there while coastal areas see lower lightning odds of about 10 to 20 percent.
- A Coastal Flood Advisory is in effect for vulnerable shorelines during high tides and officials warn of minor tidal inundation, elevated surf, dangerous rip currents, and localized flash‑flood pockets in desert canyons.
- Forecasts remain time‑sensitive but project the monsoon pulse to last through Monday and Tuesday before ridge rebuilding drives a rapid inland warmup next week, so agencies are monitoring for lightning starts, gusty outflows, and localized flash flooding.