Weather on May 21
Fontana, CA
55 Years of Data
About This Date
May 21st in Fontana, CA typically brings warm spring weather, with average highs around 80°F and lows near 55°F — a 25°F daily swing. Over 56 years of records, the warmest May 21st was in 2000 (81°F average), while the coldest was 1975 (55°F) — a 26°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 1.4°F cooler on this date compared to 20-30 years ago.
The last decade has been 1.4°F cooler on this date compared to 20-30 years ago.
Planning for May 21st in Fontana, CA? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2026 | 87° | 59° | 73° | — | — |
| 2025 | 95° | 63° | 79° | — | — |
| 2024 | 76° | 55° | 65° | — | — |
| 2023 | 84° | 60° | 72° | — | — |
| 2022 | 74° | 57° | 65° | — | — |
| 2021 | 76° | 52° | 64° | — | — |
| 2020 | 89° | 58° | 73° | — | — |
| 2019 | 66° | 56° | 61° | — | — |
| 2018 | 67° | 57° | 62° | — | — |
| 2017 | 96° | 62° | 79° | — | — |
| 2016 | 70° | 51° | 60° | — | — |
| 2015 | 69° | 57° | 63° | — | — |
| 2014 | 73° | 53° | 63° | — | — |
| 2013 | 88° | 60° | 74° | — | — |
| 2012 | 94° | 60° | 77° | — | — |
| 2011 | 80° | 53° | 67° | — | — |
| 2010 | 77° | 55° | 66° | — | — |
| 2009 | 85° | 57° | 71° | — | — |
| 2008 | 74° | 59° | 66° | — | — |
| 2007 | 64° | 56° | 60° | — | — |
| 2006 | 69° | 59° | 64° | — | — |
| 2005 | 95° | 62° | 79° | — | — |
| 2004 | 70° | 57° | 63° | — | — |
| 2003 | 100° | 63° | 81° | — | — |
| 2002 | 68° | 47° | 57° | — | — |
| 2001 | 82° | 58° | 70° | — | — |
| 2000warmest | 101° | 61° | 81° | — | — |
| 1999 | 70° | 54° | 62° | — | — |
| 1998 | 74° | 54° | 64° | — | — |
| 1997 | 84° | 63° | 73° | — | — |
| 1996 | 83° | 55° | 69° | — | — |
| 1995 | 74° | 54° | 64° | — | — |
| 1994 | 86° | 48° | 67° | — | — |
| 1993 | 80° | 59° | 70° | — | — |
| 1992 | 79° | 59° | 69° | — | — |
| 1991 | 77° | 48° | 63° | — | — |
| 1990 | 82° | 52° | 67° | — | — |
| 1989 | 90° | 54° | 72° | — | — |
| 1988 | 100° | 58° | 79° | — | — |
| 1987 | 72° | 53° | 62° | — | — |
| 1986 | 80° | 55° | 68° | — | — |
| 1985 | 85° | 53° | 69° | — | — |
| 1984 | 85° | 52° | 68° | — | — |
| 1983 | 86° | 51° | 69° | — | — |
| 1982 | 75° | 57° | 66° | — | — |
| 1981 | 76° | 42° | 59° | — | — |
| 1980 | 66° | 53° | 60° | — | — |
| 1979 | 75° | 56° | 65° | — | — |
| 1978 | 84° | 48° | 66° | — | — |
| 1977 | 87° | 55° | 71° | — | — |
| 1976 | 79° | 53° | 66° | — | — |
| 1975coldest | 65° | 46° | 55° | — | — |
| 1974 | 93° | 50° | 72° | — | — |
| 1973 | 78° | 53° | 66° | — | — |
| 1972 | 75° | 47° | 61° | — | — |
| 1971 | 77° | 53° | 65° | — | — |
Fontana, CA Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
Fontana, CA Monthly Precipitation
Average rainfall per month, in inches.
Fontana, CA Daily Temperature Calendar
Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.
Best Time to Visit Fontana, CA
Fontana, CA has no months that meet our "pleasant" threshold — every season has tradeoffs.