• Early AM

    May 25

    Lo 55°

    Cloudy

    Migraine Headache Weather
    • Hi
      RealFeel
      69°
    • UV
      4 - Moderate
    • Cloud
      Cover
      95%
    more
  • Today

    May 25

    66°Lo 54°

    Clouds giving way to some sun

    Beneficial weather for migraines
    • Hi
      RealFeel
      70°
    • UV
      7 - Very High
    • Cloud
      Cover
      67%
    more
  • Thu

    May 26

    71°Lo 51°

    Clouds giving way to sun

    Beneficial weather for migraines
    • Hi
      RealFeel
      76°
    • UV
      7 - Very High
    • Cloud
      Cover
      25%
    more
  • Fri

    May 27

    77°Lo 52°

    Turning sunny; pleasant

    Beneficial weather for migraines
    • Hi
      RealFeel
      81°
    • UV
      7 - Very High
    • Cloud
      Cover
      0%
  • Sat

    May 28

    80°Lo 51°

    Clouds breaking for sun

    Beneficial weather for migraines
    • Hi
      RealFeel
      84°
    • UV
      7 - Very High
    • Cloud
      Cover
      0%
    more
Next Previous
Hi 77° RealFeel® 81° Precipitation 0%

Day

N

E

S

W

  • W 7 mph
  • Gusts: 14 mph

Pleasant with clouds moving away to leave sunshine

  • Max UV Index: 8 (Very High)
  • Thunderstorms: 0%
  • 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® 54° Precipitation 0%

Night

N

E

S

W

  • WNW 2 mph
  • Gusts: 10 mph

Clear

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

Temperature History - May 27

more Historical Weather Data >
  Today Normal Record 5/27/2015
High 77° 73° N/A 63°
Low 52° 52° N/A 51°

Sunrise/Sunset

Sunrise / Sunset Illustration

Rises at 5:50 AM with 14:31 of sunlight, then sets at 8:21 PM

Moonrise/Moonset

Astronomy >
Moonrise / Moonset Illustration

Rises at 12:18 AM with 10:50 of moolight, then sets at 11:08 AM

Castro Valley Weather Report

San Francisco: Milder air to build ahead of Memorial Day weekend

May 25, 2016; 4:22 AM ET

Following a stretch of cool days, milder air will begin to build across the Bay area heading into Memorial Day weekend. more >

Fri. Migraine Headache

Fri. UV Index