Hayward climate
Hayward (California, United States) has a warm-summer Mediterranean climate (Köppen Csb). The average temperature over the year is 15 °C59 °F, and about 511 mm20 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Hayward climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 1558 | 540 | 1049 | 883.5 | 3 |
| Feb | 1660 | 542 | 1151 | 913.6 | 2 |
| Mar | 1763 | 644 | 1254 | 773.0 | 0 |
| Apr | 1967 | 745 | 1356 | 401.6 | 0 |
| May | 2373 | 948 | 1660 | 140.6 | 0 |
| Jun | 2780 | 1151 | 1966 | 40.1 | 0 |
| Jul | 3086 | 1254 | 2170 | 00.0 | 0 |
| Aug | 3086 | 1254 | 2170 | 10.0 | 0 |
| Sep | 2985 | 1254 | 2169 | 30.1 | 0 |
| Oct | 2577 | 1050 | 1864 | 261.0 | 0 |
| Nov | 1966 | 745 | 1355 | 532.1 | 1 |
| Dec | 1458 | 541 | 1049 | 1144.5 | 3 |
| Year | 3086 | 540 | 1559 | 51120 | 8 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 84% | 58% | 2.5 | 9:50 |
| Feb | 83% | 58% | 3.4 | 10:45 |
| Mar | 82% | 58% | 4.6 | 11:51 |
| Apr | 78% | 53% | 6.0 | 13:07 |
| May | 73% | 51% | 6.7 | 14:11 |
| Jun | 66% | 44% | 7.3 | 14:45 |
| Jul | 62% | 56% | 6.5 | 14:31 |
| Aug | 63% | 57% | 5.8 | 13:36 |
| Sep | 60% | 46% | 5.1 | 12:22 |
| Oct | 63% | 44% | 4.0 | 11:09 |
| Nov | 73% | 50% | 2.8 | 10:05 |
| Dec | 81% | 59% | 2.1 | 9:34 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Hayward is like
The warmest month is August, with an average high of 30 °C86 °F and a low of 12 °C54 °F. The coldest is January, when highs average 15 °C58 °F and lows 5 °C40 °F. There is a clear seasonal cycle, with 11.5 °C20.7 °F between the average temperature of the warmest and the coolest month.
Annual precipitation is moderate at about 511 mm20 in. The wettest three-month stretch is December–February, which brings 57% of the annual total. Months with less than 20 mm0.8 in on average: May–September. The wettest month is December (114 mm4.5 in), the driest is July (0 mm0.0 in).
Relative humidity ranges from 60% in September to 84% in January. The clearest skies (lowest average cloud amount, 44%) are typical of October. Average wind speed near the ground ranges from 6 km/h (4 mph) in January to 10 km/h (6 mph) in July. Daylight lasts from about 9.6 hours in December to 14.8 hours in June.
Best time to visit Hayward
Based on these averages, the most comfortable months for sightseeing and outdoor activities are April–July and September–November: average highs of 19 °C66 °F to 30 °C86 °F with 0 mm0.0 in to 53 mm2.1 in of precipitation per month.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Hayward
- Winter (December–February) — highs 1458 to 16 °C60 °F, lows around 5 °C40 °F, about 98 mm3.8 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket and an umbrella or light rain jacket.
- Spring (March–May) — highs 1763 to 23 °C73 °F, lows 644 to 9 °C48 °F, about 44 mm1.7 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an extra layer for the cooler mornings and evenings.
- Summer (June–August) — highs 2780 to 30 °C86 °F, lows 1151 to 12 °C54 °F, about 2 mm0.1 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an extra layer for the cooler mornings and evenings.
- Autumn (September–November) — highs 1966 to 29 °C85 °F, lows 745 to 12 °C54 °F, about 27 mm1.1 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an extra layer for the cooler mornings and evenings.
How Hayward compares
Compared with San Francisco, about 32 km to the west, Hayward is on average 1.2 °C2.2 °F warmer and receives 13% less precipitation (511 mm20 in vs 586 mm23 in). The difference is largest in July (3.7 °C6.6 °F warmer).
Of the 222 places in the United States covered by World Climates, Hayward is the 110th warmest by annual mean temperature and the 165th wettest by annual precipitation. See all of them on the United States climate page.
Places in other countries with the most similar temperature and rainfall pattern: Jerusalem (Israel, Csa), Al Bayda (Libya, BSk) and Hebron (Palestine, BSk).
The same NASA POWER grid cell also contains Sunnyvale (pop. 155,805). Their long-term averages in this dataset are essentially the same as for Hayward, so they do not have separate pages.
Nearby places
- San Francisco 32 km · 14 °C57 °F · 586 mm23 in
- Daly City 34 km · 13 °C55 °F · 516 mm20 in
- Concord 35 km · 15 °C59 °F · 467 mm18 in
- San Jose 40 km · 15 °C60 °F · 511 mm20 in
- Antioch 44 km · 15 °C60 °F · 467 mm18 in
- Vallejo 51 km · 14 °C57 °F · 586 mm23 in
- Fairfield 65 km · 15 °C60 °F · 467 mm18 in
- Stockton 76 km · 17 °C63 °F · 449 mm18 in
Frequently asked questions
What is the warmest month in Hayward?
August is the warmest month in Hayward, with an average high of 30 °C (86 °F) and an average low of 12 °C (54 °F).
What is the coldest month in Hayward?
January is the coldest month, with an average high of 15 °C (58 °F) and an average low of 5 °C (40 °F).
When does it rain the most in Hayward?
December is the wettest month with about 114 mm (4.5 in) of precipitation; July is the driest with about 0 mm (0.0 in).
What is the best time to visit Hayward?
Judging by long-term averages, the most comfortable months are April–July and September–November.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 233 m, while Hayward lies at about 34 m. Temperatures on this page were therefore adjusted by +1.3 °C2.3 °F using the standard lapse rate of 6.5 °C per 1,000 m.