Outdoor conditions in

Castro Valley

California
Now
  1. 54°Sunny0% rain59% humidityGusts 7 mph
  2. 58°Sunny0% rain52% humidityGusts 8 mph
  3. 64°Sunny0% rain42% humidityGusts 9 mph
  4. 69°Sunny0% rain37% humidityGusts 12 mph
  5. 73°Sunny0% rain34% humidityGusts 12 mph
  6. 79°Sunny0% rain30% humidityGusts 12 mph
  7. 81°Sunny0% rain27% humidityGusts 12 mph
  8. 83°Sunny0% rain24% humidityGusts 10 mph
  9. 84°Sunny0% rain22% humidityGusts 9 mph
  10. 84°Sunny0% rain20% humidityGusts 7 mph
  11. 82°Clear0% rain24% humidityGusts 3 mph
  12. 77°Clear0% rain29% humidityGusts 3 mph
  13. 71°Clear0% rain34% humidityGusts 2 mph
  14. 68°Clear0% rain37% humidityGusts 2 mph
  15. 67°Clear0% rain39% humidityGusts 2 mph
  16. 65°Clear0% rain41% humidityGusts 2 mph
  17. 64°Mostly Clear0% rain41% humidityGusts 2 mph
  18. 63°Clear0% rain42% humidityGusts 2 mph
  19. 61°Clear0% rain42% humidityGusts 3 mph
  20. 60°Clear0% rain42% humidityGusts 5 mph
  21. 60°Clear0% rain42% humidityGusts 6 mph
  22. 58°Mostly Clear0% rain43% humidityGusts 8 mph
  23. 58°Sunny0% rain43% humidityGusts 8 mph
  24. 58°Sunny0% rain44% humidityGusts 8 mph
Extra care for

A little farther out

The next five days

Today

Today looks fairly quiet.

Rain
0%
Humidity
20–60%
Wind
12 mph
Fri

Friday looks fairly quiet.

Rain
0%
Humidity
19–44%
Wind
12 mph
Sat

Saturday looks fairly quiet.

Rain
0%
Humidity
24–62%
Wind
10 mph
Sun

Sunday looks fairly quiet.

Rain
0%
Humidity
58–100%
Wind
15 mph
Mon

Monday looks fairly quiet.

Rain
5%
Humidity
66–100%
Wind
18 mph
  1. 84° / 54°Today looks fairly quiet.0% rain · Humidity 20–60% · Wind 12 mph
  2. 88° / 58°Friday looks fairly quiet.0% rain · Humidity 19–44% · Wind 12 mph
  3. 87° / 60°Saturday looks fairly quiet.0% rain · Humidity 24–62% · Wind 10 mph
  4. 72° / 53°Sunday looks fairly quiet.0% rain · Humidity 58–100% · Wind 15 mph
  5. 64° / 50°Monday looks fairly quiet.5% rain · Humidity 66–100% · Wind 18 mph

Environmental watch

Air quality + smoke

Air quality

Fremont area · Updated Thu 8:25 AM
34GoodUS AQI

Good through 12 PM.

Sky check

No plume detected overhead

Satellite view · Updated Thu 5:45 AM

Air near ground34 · Good US AQI

Rain, in motion · Past four hours

Castro Valley radar

Ready when you areSee what is moving toward Castro Valley.

Watch the last four hours of rain, then search any nearby trail, lake, or address.

View the official forecast ↗

Outdoor fire check

Thinking about a backyard fire?

Use extra caution.

There is no lower-concern three-hour stretch in the next 12 hours.

Next 12 hoursChoose a time to see what is driving the concern.
Selected timeNowLower weather concern

Humidity is 59% with light wind and gusts below 8 mph.

Humidity
59%
Wind
3 mph
Gusts
7 mph

Check local rules. Weather is only part of the decision. Check city, county, and land-manager fire restrictions before lighting any outdoor fire.

Nearby regional view

Explore Oakland

About 10 miles away, the Oakland hub looks more deeply at Oakland, CA. It reflects that wider area rather than Castro Valley’s exact conditions.

About these readingsSources and local limits

Weather

Forecasts, alerts, and radar come from NOAA and the National Weather Service.

Air quality

This reading describes Fremont area, about 11 miles away. Conditions can differ at this exact spot.

Smoke

Satellite imagery shows smoke overhead. It cannot tell us how much smoke has reached breathing level.

This page represents Castro Valley, CA, so conditions can vary from street to street. Environmental data: AirNow · participating air agencies · preliminary real-time US AQI · NOAA Hazard Mapping System · satellite-observed smoke.