San Jose, at the southern end of the San Francisco Bay, has a Mediterranean climate with around 380 mm (about 15 inches) of rain a year, concentrated almost entirely in the winter months with a long, dry summer typical of coastal California. Because the surrounding hills can intensify incoming Pacific storms, and because much of the South Bay sits on relatively flat, low-lying former marshland, sustained heavy rain, particularly from atmospheric river events, can cause localized flooding along the region’s creeks, as seen during severe flooding in 2017. Because a typical summer week here involves essentially no rain, radar is most useful during the relatively concentrated winter storm season. NWS Doppler radar KMUX (San Francisco Bay Area) covers the region.
Learn more: How Does Rain Radar Work? · Open the full Rain Map
Frequently Asked Questions
Is it raining in San Jose right now?
The live radar map above shows precipitation over San Jose, California in real time. Blue shades indicate light rain, while yellow, orange, and red mark heavier downpours. If no colored echoes appear over San Jose, no significant rain is currently being detected.
How often does the San Jose rain radar update?
The radar refreshes continuously, typically every few minutes, so the map reflects current conditions rather than an hours-old forecast. Press play to animate the most recent frames.
Can I see if a storm is heading toward San Jose?
Yes. Press play on the radar to animate the last few hours of rainfall and watch which way rain cells over California are moving – the clearest way to judge whether a shower will reach San Jose or pass by.
Is this San Jose rain radar free to use?
Yes, completely free – no account, app download, or sign-up required. It works in any browser on desktop and mobile.