0.7in

Rain Today

Rain Last Hour
0.02in

Recorded at Hayward, Hayward Air Terminal Updated 13 mins ago (3.2 miles away)

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Real-Time Extremes

Hottest 87.7 °F
El Salvador International Airport, FL
Coldest -58.1 °F
Northway, Northway Airport, AK
Windiest 47.2mph
Mount Washington, NH
Wettest (Last Hour) 0.2in
Monterey Regional Airport, CA
Most Humid 100%
Hobby Field Airport, OR
Least Humid 17%
Fort Carson, CO
Highest Pressure 1026.1 hPa
Deadhorse, Alpine Airstrip, AK
Lowest Pressure 968.2 hPa
Adak Island, Adak Airport, AK

Trending Locations

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Castro Valley Rainfall Forecast

Today 4 Jan
95%
Mon 5 Jan
80%
Tue 6 Jan
15%
Wed 7 Jan
20%
Thu 8 Jan
5%
Fri 9 Jan
No Rain
Sat 10 Jan
No Rain

Castro Valley Rainfall Statistics

January Rainfall

Hayward, Hayward Air Terminal (3.1 miles)

Total Rainfall 2026
0.7in
Daily Average 2026
0.3in
Wettest Day 1 January, 2026
0.6in
Wet Days 2026
2/4 (50%)
Total Rainfall December
3.1in
Daily Average December
0.1in
Wettest Day 25 December, 2025
1in
Wet Days December
8/31 (26%)
Total Rainfall January
0.7in
Daily Average January
0.3in
Wettest Day 1 January, 2026
0.6in
Wet Days January
2/4 (50%)

Climate (2010–Present)

Hayward, Hayward Air Terminal (3.1 miles)

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Annual Average 2021–2025
19.4in
Monthly Average 2021–2025
1.6in
Daily Average 2021–2026
0.1in
Wettest Day 31 December, 2022
4.3in

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