Castro Valley, CA Live Doppler Radar

Live radar for Castro Valley, Alameda County: every NWS radar combined, rain, snow and ice colors, flash-flood risk, storm tracks and official warnings.

Open live radar for Castro ValleyWhat TALON shows

What weather hits Castro Valley?

Since 1996, the National Weather Service has logged river or areal flooding on 73 days in the San Francisco Bay Shoreline forecast zone and Alameda County — the most common reported hazard around Castro Valley, mostly in February and December. Next come high winds (26 days) and flash flooding (16 days).

HazardDays reportedMost recentWorst on record
Flooding73Jan 2026Mar 10, 2023 · 1 death
High winds26Jan 2026Oct 13, 2009 · $2.5 million damage
Flash flooding16Dec 2025Feb 3, 1998 · $250,000 damage
Debris flows14Jan 2023Jan 21, 2012 · $75,000 damage
Excessive heat10Mar 2026May 17, 2009 · $10,000 damage
Coastal flooding4Jan 2026—
Damaging thunderstorm winds3Dec 2024Apr 7, 2017 · $10,000 damage
Lightning casualties & damage2Aug 2020Oct 6, 2011 · $3,000 damage

Source: NOAA NCEI Storm Events Database, 1996–2026 (the latest year is partial). A "day" is a date with at least one report in the San Francisco Bay Shoreline forecast zone and Alameda County; damage is as reported, not adjusted for inflation.

Which radars cover Castro Valley?

The closest NEXRAD Doppler radar is KMUX (San Francisco, CA), about 39 miles south-southeast. Radar beams climb as they travel, so the height of the lowest scan over town decides how low in a storm the radar can see.

RadarDistanceLowest beam over Castro ValleyView
KMUX
San Francisco, CA		39 mi south-southeast2,600 ftExcellent — the lowest scan sees close to the ground
KDAX
Sacramento, CA		59 mi north-northeast4,400 ftGood — most storms and steady rain or snow show clearly
KBBX
Beale AFB, CA		126 mi north13,700 ftLimited — the beam overshoots the lowest part of storms

Beam height is the center of the 0.5° scan above the radar, with standard refraction. Mountains near a radar can block it further.

Tornado & hail history near Castro Valley

Since 1950, NOAA has recorded 14 tornadoes within 25 miles of Castro Valley, 2 of them EF2/F2 or stronger. Most came in January and April. The strongest was an F2 on May 5, 1998, which touched down about 23 miles south of town. The most recent was an EF1 on January 23, 2010, which touched down about 22 miles northeast of town.

Source: NOAA Storm Prediction Center — tornadoes 1950–2025, hail 1955–2025. Distances are to each tornado's track; ratings before February 2007 use the original Fujita scale.

On TALON you get Castro Valley's live radar loop, rain/snow/ice colors, flash-flood risk, storm tracks with arrival times and NWS warnings free; close-up radar and rotation detection are part of TALON Pro.

Castro Valley radar FAQ

Where is the nearest weather radar to Castro Valley, CA?

KMUX (San Francisco, CA), about 39 miles south-southeast. KDAX (Sacramento, CA) is 59 miles away and also covers the area.

How often does Castro Valley flood?

Since 1996 the National Weather Service has logged river or areal flooding on 73 days in the San Francisco Bay Shoreline forecast zone and Alameda County; the deadliest was on March 10, 2023, with 1 death. TALON's free flash-flood risk layer shows, every 2 minutes, how close the rain that has fallen is to what it takes to flood — turn it on under Layers.

Is TALON's radar for Castro Valley free?

Yes — the US radar loop, rain/snow/ice colors, flash-flood risk, storm tracks and NWS warnings are free in any browser. Close-up radar, rotation detection and longer forecasts are part of TALON Pro.

Should I rely on radar for my safety?

No app replaces official warnings. When the National Weather Service issues a warning for Castro Valley, follow it right away — see watch vs. warning.

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