Hourly Weather Forecast - Castro Valley, CA

12 AM
48°F
90%
12mph
S
Rain
Humidity
91%
Feels like
43°F
Dew Point
46°F
1 AM
48°F
90%
12mph
S
Rain
Humidity
92%
Feels like
43°F
Dew Point
46°F
2 AM
48°F
80%
11mph
S
80% Chance of Light Rain
Humidity
93%
Feels like
43°F
Dew Point
46°F
3 AM
48°F
80%
11mph
S
80% Chance of Light Rain
Humidity
92%
Feels like
43°F
Dew Point
46°F
4 AM
48°F
70%
11mph
S
70% Chance of Light Rain
Humidity
91%
Feels like
43°F
Dew Point
46°F
5 AM
49°F
70%
10mph
SSE
70% Chance Rain Showers
Humidity
93%
Feels like
44°F
Dew Point
47°F
6 AM
49°F
70%
10mph
SSE
70% Chance Rain Showers
Humidity
92%
Feels like
45°F
Dew Point
47°F
7 AM
49°F
60%
10mph
SSE
60% Chance Rain Showers
Humidity
92%
Feels like
45°F
Dew Point
47°F
7:21 AM
8 AM
49°F
60%
10mph
SSE
60% Chance Rain Showers
Humidity
92%
Feels like
45°F
Dew Point
47°F
9 AM
50°F
50%
10mph
SSE
50% Chance Rain Showers
Humidity
94%
Feels like
46°F
Dew Point
48°F
10 AM
50°F
60%
10mph
S
60% Chance Rain Showers
Humidity
94%
Feels like
50°F
Dew Point
49°F
11 AM
51°F
70%
11mph
S
70% Chance Rain Showers
Humidity
94%
Feels like
51°F
Dew Point
50°F
12 PM
52°F
70%
11mph
S
70% Chance Rain Showers
Humidity
93%
Feels like
52°F
Dew Point
50°F
1 PM
53°F
70%
11mph
S
70% Chance Rain Showers
Humidity
92%
Feels like
53°F
Dew Point
50°F
2 PM
52°F
70%
10mph
S
70% Chance Rain Showers
Humidity
93%
Feels like
52°F
Dew Point
50°F
3 PM
50°F
70%
10mph
S
70% Chance Rain Showers
Humidity
97%
Feels like
46°F
Dew Point
49°F

Rain And Snow Totals Through Monday

Atmospheric River Takes Aim For Northern California

The plume of abundant moisture impacting the Northwest the last several days will focus more on Northern California later today into Monday bringing heavy rainfall and mountain snow.

NOAA, NCDC

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Sunday's Weather Outlook

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During Extreme Cold: Watch for Frostbite!

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Watch vs. Warning

Flash Flood Watch and Warning Defined

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