Northern California flooding doesn’t need a hurricane to wreck your commute. It only needs one thing: water moving faster than you expected, across a road you assumed was “fine.” If you’re driving in or around the Bay Area and North Bay, treat flood alerts as a real-world traffic problem, not background noise.
The National Weather Service flood warning for Sonoma County spells it out: flooding can be imminent or already happening, and drainage can stay overwhelmed for hours as runoff works through the system. That’s why “the rain let up” doesn’t mean “the roads are fine.”
What to do during Northern California flooding
Quick translation: a flood watch means conditions are possible; a flood warning means it’s happening or about to. If you see “warning,” treat it like a closure sign, not a suggestion.
Start with the simplest rule: don’t commit to a route you haven’t checked in the last 10 minutes. If you can choose between freeway and surface streets, take the higher, better-lit route. Caltrans QuickMap shows closures, incidents, and trouble spots, and it beats guessing…