Weather on May 15
Rialto, CA
55 Years of Data
Avg High
78°F
Avg Low
54°F
Warmest
2014
84°F avg
Coldest
2011
50°F avg
About This Date
May 15th in Rialto, CA typically brings pleasant spring weather, with average highs around 78°F and lows near 54°F. Over 48 years of records, the warmest May 15th was in 2014 (84°F average), while the coldest was 2011 (50°F) — a 34°F range across recorded history. Rain or other precipitation has occurred on about 4% of May 15th dates historically, with the wettest May 15th recording 1.04" of rain.
Planning for May 15th in Rialto, CA? Great weather for outdoor activities.
Cooling Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 82° | 52° | 67° | — | — |
| 2017 | 58° | 49° | 53° | — | — |
| 2016 | 63° | 54° | 58° | — | — |
| 2015 | 60° | 48° | 54° | — | — |
| 2014warmest | 97° | 71° | 84° | — | — |
| 2013 | 78° | 54° | 66° | — | — |
| 2012 | 81° | 52° | 66° | — | — |
| 2011coldest | 58° | 43° | 50° | — | — |
| 2010 | 85° | 50° | 67° | — | — |
| 2009 | 92° | 61° | 76° | — | — |
| 2008 | 92° | 65° | 78° | — | — |
| 2007 | 74° | 49° | 61° | — | — |
| 2006 | 83° | 56° | 69° | — | — |
| 2005 | 90° | 60° | 75° | — | — |
| 2004 | 85° | 59° | 72° | — | — |
| 2003 | 75° | 47° | 61° | — | — |
| 2002 | 78° | 49° | 63° | — | — |
| 2001 | 82° | 50° | 66° | — | — |
| 2000 | 73° | 50° | 62° | — | — |
| 1999 | 68° | 51° | 60° | — | — |
| 1998 | 72° | 45° | 58° | — | — |
| 1997 | 93° | 58° | 75° | — | — |
| 1996 | 80° | 57° | 69° | — | — |
| 1995 | 66° | 46° | 56° | — | — |
| 1994 | 66° | 58° | 62° | — | — |
| 1993 | 85° | 62° | 73° | — | — |
| 1992 | 75° | 52° | 63° | — | — |
| 1991 | 83° | 48° | 65° | — | — |
| 1990 | 71° | 55° | 63° | — | — |
| 1989 | 57° | 54° | 55° | 1.04" | — |
| 1988 | 87° | 56° | 71° | — | — |
| 1987 | 79° | 62° | 70° | — | — |
| 1986 | 71° | 55° | 63° | — | — |
| 1985 | 86° | 53° | 70° | — | — |
| 1984 | 76° | 53° | 64° | — | — |
| 1983 | 83° | 54° | 68° | — | — |
| 1982 | 82° | 53° | 68° | — | — |
| 1981 | 66° | 55° | 61° | 0.18" | — |
| 1980 | 68° | 53° | 61° | — | — |
| 1979 | 88° | 51° | 69° | — | — |
| 1978 | 83° | 57° | 70° | — | — |
| 1977 | 64° | 54° | 59° | — | — |
| 1976 | 89° | 57° | 73° | — | — |
| 1975 | 76° | 54° | 65° | — | — |
| 1974 | 64° | 55° | 60° | — | — |
| 1973 | 83° | 53° | 68° | — | — |
| 1972 | 93° | 53° | 73° | — | — |
| 1971 | 82° | 53° | 68° | — | — |
48 years of data from DEVORE CALIFORNIA