Weather on August 11
Rialto, CA
55 Years of Data
Avg High
95°F
Avg Low
65°F
Warmest
2012
92°F avg
Coldest
1999
68°F avg
About This Date
August 11th in Rialto, CA typically brings hot summer weather, with average highs around 95°F and lows near 65°F — a 30°F daily swing. Over 48 years of records, the warmest August 11th was in 2012 (92°F average), while the coldest was 1999 (68°F) — a 24°F range across recorded history. This date has historically been dry, with little recorded precipitation.
Planning for August 11th in Rialto, CA? Stay hydrated and seek shade during peak afternoon hours.
Cooling Trend
0.5°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 99° | 70° | 84° | — | — |
| 2017 | 97° | 69° | 83° | — | — |
| 2016 | 91° | 59° | 75° | — | — |
| 2015 | 86° | 58° | 72° | — | — |
| 2014 | 92° | 68° | 80° | — | — |
| 2013 | 86° | 56° | 71° | — | — |
| 2012warmest | 105° | 78° | 92° | — | — |
| 2011 | 83° | 57° | 70° | — | — |
| 2010 | 84° | 55° | 70° | — | — |
| 2009 | 92° | 62° | 77° | — | — |
| 2008 | 90° | 64° | 77° | — | — |
| 2007 | 93° | 62° | 78° | — | — |
| 2006 | 91° | 65° | 78° | — | — |
| 2005 | 92° | 63° | 77° | — | — |
| 2004 | 104° | 72° | 88° | — | — |
| 2003 | 99° | 73° | 86° | — | — |
| 2002 | 104° | 72° | 88° | — | — |
| 2001 | 98° | 67° | 82° | — | — |
| 2000 | 104° | 73° | 89° | — | — |
| 1999coldest | 85° | 52° | 68° | — | — |
| 1998 | 101° | 69° | 85° | — | — |
| 1997 | 87° | 58° | 72° | — | — |
| 1996 | 103° | 68° | 85° | — | — |
| 1995 | 99° | 68° | 83° | — | — |
| 1994 | 104° | 72° | 88° | — | — |
| 1993 | 93° | 62° | 78° | — | — |
| 1992 | 97° | 71° | 84° | — | — |
| 1991 | 88° | 68° | 78° | — | — |
| 1990 | 102° | 69° | 86° | — | — |
| 1989 | 95° | 67° | 81° | — | — |
| 1988 | 87° | 59° | 73° | — | — |
| 1987 | 92° | 64° | 78° | — | — |
| 1986 | 96° | 64° | 80° | — | — |
| 1985 | 86° | 62° | 74° | — | — |
| 1984 | 96° | 65° | 80° | — | — |
| 1983 | 99° | 66° | 82° | — | — |
| 1982 | 96° | 63° | 79° | — | — |
| 1981 | 100° | 64° | 82° | — | — |
| 1980 | 107° | 69° | 88° | — | — |
| 1979 | 92° | 69° | 80° | — | — |
| 1978 | 90° | 74° | 82° | — | — |
| 1977 | 100° | 61° | 80° | — | — |
| 1976 | 98° | 57° | 78° | — | — |
| 1975 | 96° | 63° | 79° | — | — |
| 1974 | 93° | 59° | 76° | — | — |
| 1973 | 97° | 60° | 78° | — | — |
| 1972 | 98° | 67° | 82° | — | — |
| 1971 | 105° | 70° | 87° | — | — |
48 years of data from FONTANA 5 N