• Today

    Jul 30

    82°Lo 56°

    Sunny to partly cloudy

    Low ragweed pollen levels
    • Grass
      Pollen
      1 - Low
    • Ragweed
      Pollen
      1 - Low
    • Tree
      Pollen
      1 - Low
  • Sun

    Jul 31

    79°Lo 58°

    Clouds, then sun

    Low ragweed pollen levels
    • Grass
      Pollen
      1 - Low
    • Ragweed
      Pollen
      1 - Low
    • Tree
      Pollen
      1 - Low
    more
  • Mon

    Aug 1

    78°Lo 56°

    Areas of fog, then sun

    Low ragweed pollen levels
    • Grass
      Pollen
      1 - Low
    • Ragweed
      Pollen
      1 - Low
    • Tree
      Pollen
      1 - Low
    more
  • Tue

    Aug 2

    79°Lo 54°

    Mostly sunny and nice

    Low ragweed pollen levels
    • Grass
      Pollen
      1 - Low
    • Ragweed
      Pollen
      1 - Low
    • Tree
      Pollen
      1 - Low
    more
  • Wed

    Aug 3

    81°Lo 55°

    Fog to sun

    Low ragweed pollen levels
    • Grass
      Pollen
      1 - Low
    • Ragweed
      Pollen
      1 - Low
    • Tree
      Pollen
      1 - Low
    more
Next Previous
Next 8 hours >
  Sat
5pm
6pm 7pm 8pm 9pm 10pm 11pm Sun
12am
  5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
Forecast
Mostly Sunny
Mostly Sunny
Mostly Sunny
Mostly Sunny
Mostly Clear
Mostly Clear
Mostly Clear
Mostly Clear
Temp (°F) 78° 75° 71° 66° 63° 61° 60° 59°
RealFeel® 77° 73° 68° 63° 61° 60° 59° 58°
Humidity 47% 49% 56% 64% 69% 75% 80% 81%
   
  5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
Rain
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
Snow
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
Ice
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
 
0%
   
  5pm 6pm 7pm 8pm 9pm 10pm 11pm 12am
Wind (mph) 14 WNW 13 WNW 12 WNW 9 WNW 8 W 7 W 6 WSW 5 WSW
UV Index 3 1 0 0 0 0 0 0
Cloud Cover 19% 11% 12% 25% 25% 25% 25% 25%
Dew Point 56° 55° 55° 54° 53° 54° 54° 53°
Middle Grid line 80 F Middle Grid line 75 F Middle Grid line 70 F Middle Grid line 65 F Middle Grid line 60 F Middle Grid line 55 F

Temperature History - Jul 30

more Historical Weather Data >
  Today Normal Record 7/30/2015
High 82° 78° N/A 79°
Low 56° 57° N/A 59°

Sunrise/Sunset

Sunrise / Sunset Illustration

Rises at 6:11 AM with 14:07 of sunlight, then sets at 8:18 PM

Moonrise/Moonset

Astronomy >
Moonrise / Moonset Illustration

Rises at 3:09 AM with 14:31 of moolight, then sets at 5:40 PM

Castro Valley Weather Report

Western US: Diminishing heat to aid in firefighting efforts next week

July 30, 2016; 4:48 PM ET

As several large fires continue to rage across the western United States, weather conditions will gradually improve for firefighting efforts in the upcoming week. more >

Sat. Pollen

Sat. Dust & Dander

Sat. Wind Maps