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Hayward, CA Weather on May 15
May 15th in Hayward, CA typically brings mild spring weather, with average highs around 69°F and lows near 52°F. Over 52 years of records, the warmest May 15th was in 2008 (80°F average), while the coldest was 1999 (52°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 12% of May 15th dates historically, with the wettest May 15th recording 1.42" of rain. Temperatures on this date have remained relatively stable over the past several decades.
What to Expect on May 15
Planning for May 15th in Hayward, CA? Great weather for outdoor activities.
May 15 Weather Records for Hayward
- •The all-time record high for May 15th in Hayward, CA is 99°F, set in 2008.
- •The coldest May 15th on record dropped to 42°F in 1974.
- •Temperatures have reached 90°F or higher on May 15th in 1 of the last 52 years.
Frequently Asked Questions
What was the warmest May 15 ever in Hayward?
The warmest May 15 in Hayward, CA reached 99°F in 2008. That is 30°F above the long-term average high of 69°F.
What was the coldest May 15 ever in Hayward?
The coldest May 15 in Hayward, CA dropped to 42°F in 1974. That is 10°F below the long-term average low of 52°F.
What is the average temperature on May 15 in Hayward?
On May 15, Hayward averages a high of 69°F and a low of 52°F based on 52 years of NOAA weather observations from HAYWARD AIR TERMINAL.
How many years of weather data are available for May 15 in Hayward?
We have 52 years of weather records for May 15 in Hayward, CA, sourced from NOAA's Global Historical Climatology Network. Records include daily high and low temperatures, precipitation, and snowfall data going back to 2025.
May 15 Weather History in Hayward
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 76°F | 53°F | 0" | -- |
| 2024 | 72°F | 56°F | 0" | -- |
| 2023 | 70°F | 54°F | 0" | -- |
| 2022 | 64°F | 53°F | 0" | -- |
| 2021 | 61°F | 51°F | 0.08" | -- |
| 2020 | 69°F | 56°F | 0.05" | -- |
| 2019 | 66°F | 54°F | 1.42" | -- |
| 2018 | 66°F | 56°F | 0" | -- |
| 2017 | 66°F | 52°F | 0" | -- |
| 2016 | 68°F | 57°F | 0" | -- |
| 2015 | 62°F | 52°F | 0" | -- |
| 2014 | 84°F | 58°F | 0" | -- |
| 2013 | 64°F | 53°F | 0" | -- |
| 2012 | 64°F | 53°F | 0" | -- |
| 2011 | 61°F | 47°F | 0.08" | -- |
| 2010 | 65°F | 51°F | 0" | -- |
| 2009 | 71°F | 53°F | 0" | -- |
| 2008 | 99°F | 62°F | 0" | -- |
| 2007 | 56°F | 51°F | 0" | -- |
| 2006 | 82°F | 58°F | 0" | -- |
| 2005 | 71°F | 60°F | 0" | -- |
| 2004 | 64°F | 54°F | 0" | -- |
| 2003 | 62°F | 52°F | 0" | -- |
| 2002 | 67°F | 51°F | 0" | -- |
| 2001 | 73°F | 58°F | 0" | -- |
| 2000 | 66°F | 54°F | 0.64" | -- |
| 1999 | 61°F | 44°F | 0" | -- |
| 1998 | 62°F | 46°F | -- | -- |
| 1997 | 82°F | 58°F | -- | -- |
| 1996 | 63°F | 57°F | -- | -- |
| 1995 | 68°F | 54°F | -- | -- |
| 1994 | 62°F | 50°F | -- | -- |
| 1993 | 67°F | 50°F | -- | -- |
| 1989 | 68°F | 50°F | 0" | -- |
| 1988 | 76°F | 51°F | 0" | -- |
| 1987 | 87°F | 58°F | 0" | -- |
| 1986 | 73°F | 48°F | 0" | -- |
| 1985 | 78°F | 50°F | 0" | -- |
| 1984 | 65°F | 46°F | 0" | -- |
| 1983 | 71°F | 50°F | 0" | -- |
| 1982 | 67°F | 49°F | 0" | -- |
| 1981 | 63°F | 52°F | 0" | -- |
| 1980 | 64°F | 49°F | 0" | -- |
| 1979 | 76°F | 50°F | 0" | -- |
| 1978 | 70°F | 55°F | 0.08" | -- |
| 1977 | 66°F | 46°F | 0" | -- |
| 1976 | 70°F | 48°F | 0" | -- |
| 1975 | 59°F | 48°F | 0" | -- |
| 1974 | 68°F | 42°F | 0" | -- |
| 1973 | 69°F | 55°F | 0" | -- |
| 1972 | 83°F | 49°F | 0" | -- |
| 1971 | 73°F | 46°F | 0" | -- |
Based on 52 years of data from NOAA station: HAYWARD AIR TERMINAL
Monthly Climate Averages
Historical temperature and precipitation averages for Hayward, CA, based on 55+ years of weather data.
Temperatures in Fahrenheit. Precipitation and snowfall in inches.