Go Back
  • For Business
  • |
  • Warnings
  • Data Suite
  • Forensics
  • Advertising
  • Superior Accuracy™
High-risk tornado outbreak unfolds across the Plains. Click for the forecast. Chevron right
Heat wave brings summerlike weather to the East. See how hot it will get this week. Chevron right

Castro Valley, CA

75°F
Location Chevron down
Location News Videos
Use Current Location
Recent

Castro Valley

California

75°
No results found.
Try searching for a city, zip code or point of interest.
Create Your Account Unlock extended daily and hourly forecasts — all with your free account.
Let's Go Chevron right
Have an account already? Log In
settings
Help
Castro Valley, CA Weather
Today WinterCast Local {stormName} Tracker Hourly 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities

Around the Globe

Hurricane Tracker

Severe Weather

Radar & Maps
News

News & Features

Astronomy

Business

Climate

Health

Recreation

Sports

Travel
For Business

Warnings

Data Suite

Forensics

Advertising

Superior Accuracy™

Video

Winter Center
Today Hourly 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities
May 18

Morning

5/18
82°
RealFeel® 87°
Very Warm
RealFeel Guide
Very Warm
82° to 89°
Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.
LEARN MORE
RealFeel Shade™ 78°
Pleasant
RealFeel Guide
Pleasant
63° to 81°
Most consider this temperature range ideal.
LEARN MORE
Sunny, breezy and warm

WindENE 15 mph

Wind Gusts33 mph

Humidity21%

Dew Point31°

Probability of Precipitation1%

Precipitation0.00 in

Cloud Cover0%

Visibility11 mi

Afternoon

Day & Night

Sun & Moon

14 hrs 18 mins
Rise 5:56 AM
Set 8:14 PM
Waxing Crescent
Rise 7:14 AM
Set 11:08 PM

Temperature History

5/18
High
Low
Forecast
85°
54°
Average
69°
53°
Last Year
75°
46°

Around the Globe

Hurricane Tracker

Severe Weather

Radar & Maps

News

Video

Winter Center

Top Stories

Severe Weather

High-risk tornado outbreak unfolds across Plains into Monday night

3 hours ago

Weather Forecasts

Heat wave to complete spring weather whiplash, worsen drought in East

25 minutes ago

Astronomy

Crescent moon is about to join Venus and Jupiter in evening sky

5 hours ago

Weather Forecasts

Wildfire risk to focus across the Southwest, Plains

15 minutes ago

Winter Weather

Winter to return to Colorado, Wyoming with more May mountain snow

8 hours ago

 More Stories

Featured Stories

Astronomy

Watch an asteroid safely pass close to Earth on Monday

3 hours ago

Severe Weather

10 types of tornadoes that occur in the US

5 hours ago

Astronomy

SpaceX poised for first Starship flight test of 2026

2 days ago

Severe Weather

Does a green sky mean a tornado is coming?

5 hours ago

Climate

Turkmenistan's fiery 'Gates of Hell' crater is dimming

3 days ago
World North America United States California Castro Valley

Weather Near Castro Valley:

  • Oakland, CA
  • San Francisco, CA
  • San Jose, CA
Company
Proven Superior Accuracy™ About AccuWeather Digital Advertising Careers Press Contact Us
Products & Services
For Business For Partners For Advertising AccuWeather APIs AccuWeather Connect Personal Weather Stations
Apps & Downloads
iPhone App Android App See all Apps & Downloads
Subscription Services
AccuWeather Premium AccuWeather Professional
More
AccuWeather Ready Business Health Hurricane Leisure and Recreation Severe Weather Space and Astronomy Sports Travel Weather News Winter Center
Company
Proven Superior Accuracy™ About AccuWeather Digital Advertising Careers Press Contact Us
Products & Services
For Business For Partners For Advertising AccuWeather APIs AccuWeather Connect Personal Weather Stations
Apps & Downloads
iPhone App Android App See all Apps & Downloads
Subscription Services
AccuWeather Premium AccuWeather Professional
More
AccuWeather Ready Business Health Hurricane Leisure and Recreation Severe Weather Space and Astronomy Sports Travel Weather News Winter Center
© 2026 AccuWeather, Inc. "AccuWeather" and sun design are registered trademarks of AccuWeather, Inc. All Rights Reserved.
Terms of Use | Privacy Policy | Cookie Policy | About Your Privacy Do Not Sell or Share My Personal Information | Data Sources

...

...

...