• Today

    Apr 21

    61°Lo 52°

    Mostly cloudy and breezy

    Good for an outdoor bbq
    • Precip
      2%
    • Hi
      RealFeel
      60°
    • Wind
      Gust
      24 mph
  • Wed

    Apr 22

    69°Lo 50°

    Warmer

    Very Good for an outdoor bbq
    • Precip
      6%
    • Hi
      RealFeel
      74°
    • Wind
      Gust
      16 mph
    more
  • Thu

    Apr 23

    64°Lo 48°

    Breezy with some sun

    Good for an outdoor bbq
    • Precip
      3%
    • Hi
      RealFeel
      67°
    • Wind
      Gust
      25 mph
    more
  • Fri

    Apr 24

    63°Lo 46°

    Partly sunny and breezy

    Good for an outdoor bbq
    • Precip
      7%
    • Hi
      RealFeel
      63°
    • Wind
      Gust
      25 mph
    more
  • Sat

    Apr 25

    67°Lo 49°

    Partly sunny

    Very Good for an outdoor bbq
    • Precip
      2%
    • Hi
      RealFeel
      71°
    • Wind
      Gust
      17 mph
    more
Next Previous
Hi 61° RealFeel® 60° Precipitation 2%

Day

N

E

S

W

  • WNW 14 mph
  • Gusts: 24 mph

Mostly cloudy and breezy

  • Max UV Index: 4 (Moderate)
  • Thunderstorms: 1%
  • Precipitation: 0 in
  • Rain: 0 in
  • Snow: 0 in
  • Ice: 0 in
  • Hours of Precipitation: 0 hrs
  • Hours of Rain: 0 hrs
Lo 52° RealFeel® 47° Precipitation 2%

Night

N

E

S

W

  • WSW 9 mph
  • Gusts: 15 mph

Mostly cloudy

  • Max UV Index: N/A
  • Thunderstorms: 2%
  • Precipitation: 0 in
  • Rain: 0 in
  • Snow: 0 in
  • Ice: 0 in
  • Hours of Precipitation: 0 hrs
  • Hours of Rain: 0 hrs

Temperature History - Apr 21

more Historical Weather Data >
  Today Normal Record 4/21/2014
High 61° N/A N/A 66°
Low 52° N/A N/A 48°

Sunrise/Sunset

Sunrise / Sunset Illustration

Rises at 6:25 AM with 13:24 of sunlight, then sets at 7:49 PM

Moonrise/Moonset

Astronomy >
Moonrise / Moonset Illustration

Rises at 8:49 AM with 14:25 of moolight, then sets at 11:14 PM

Castro Valley Weather Report

San Francisco: Clouds, Showers to Linger Ahead of Weekend

April 21, 2015; 6:20 AM ET

While cloudy conditions can be expected over the San Francisco area for the next several days, showers will not make a return until the middle of the week. more >

Is Your Outdoor Gear Waterproof?

Dec 5, 2012; 5:00 AM ET Now that it's cold enough to hit the slopes, you may want to look more closely at what materials your winter sports gear is made of. As it turns out, not all waterproofing is created equal.

Tue. Outdoor Entertaining

Tue. Wind Maps

Tue. UV Index