Weather on May 18
Mission Viejo, CA
55 Years of Data
Avg High
74°F
Avg Low
55°F
Warmest
2008
81°F avg
Coldest
1974
54°F avg
About This Date
May 18th in Mission Viejo, CA typically brings pleasant spring weather, with average highs around 74°F and lows near 55°F. Over 55 years of records, the warmest May 18th was in 2008 (81°F average), while the coldest was 1974 (54°F) — a 27°F range across recorded history. Rain or other precipitation has occurred on about 4% of May 18th dates historically. The last decade has been 2.0°F cooler on this date compared to 20-30 years ago.
The last decade has been 2.0°F cooler on this date compared to 20-30 years ago.
Planning for May 18th in Mission Viejo, CA? Great weather for outdoor activities.
Cooling Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 70° | 54° | 62° | — | — |
| 2024 | 72° | 56° | 64° | — | — |
| 2023 | 66° | 55° | 61° | — | — |
| 2022 | 73° | 55° | 64° | — | — |
| 2021 | 74° | 55° | 64° | — | — |
| 2020 | 69° | 56° | 62° | — | — |
| 2019 | 71° | 49° | 60° | — | — |
| 2018 | 68° | 54° | 61° | — | — |
| 2017 | 72° | 49° | 60° | — | — |
| 2016 | 75° | 58° | 66° | — | — |
| 2015 | 68° | 52° | 60° | — | — |
| 2014 | 75° | 56° | 65° | — | — |
| 2013 | 72° | 56° | 64° | — | — |
| 2012 | 71° | 55° | 63° | — | — |
| 2011 | 62° | 50° | 56° | — | — |
| 2010 | 71° | 51° | 61° | — | — |
| 2009 | 87° | 55° | 71° | — | — |
| 2008warmest | 95° | 67° | 81° | — | — |
| 2007 | 74° | 54° | 64° | — | — |
| 2006 | 62° | 57° | 60° | — | — |
| 2005 | 81° | 54° | 67° | — | — |
| 2004 | 75° | 55° | 65° | — | — |
| 2003 | 73° | 54° | 63° | — | — |
| 2002 | 64° | 55° | 60° | — | — |
| 2001 | 74° | 57° | 65° | — | — |
| 2000 | 79° | 52° | 65° | — | — |
| 1999 | 76° | 49° | 62° | — | — |
| 1998 | 76° | 49° | 62° | — | — |
| 1997 | 75° | 62° | 69° | — | — |
| 1996 | 76° | 56° | 66° | — | — |
| 1995 | 71° | 56° | 63° | — | — |
| 1994 | 66° | 51° | 59° | 0.13" | — |
| 1993 | 77° | 57° | 67° | — | — |
| 1992 | 80° | 62° | 71° | — | — |
| 1991 | 69° | 52° | 60° | — | — |
| 1990 | 69° | 55° | 62° | — | — |
| 1989 | 70° | 56° | 63° | — | — |
| 1988 | 70° | 53° | 61° | — | — |
| 1987 | 68° | 58° | 63° | — | — |
| 1986 | 86° | 56° | 71° | — | — |
| 1985 | 73° | 48° | 61° | — | — |
| 1984 | 79° | 56° | 67° | — | — |
| 1983 | 88° | 56° | 72° | — | — |
| 1982 | 71° | 56° | 63° | — | — |
| 1981 | 80° | 56° | 68° | — | — |
| 1980 | 74° | 59° | 66° | — | — |
| 1979 | 69° | 54° | 61° | — | — |
| 1978 | 88° | 58° | 73° | — | — |
| 1977 | 71° | 46° | 59° | — | — |
| 1976 | 80° | 54° | 67° | — | — |
| 1975 | 72° | 55° | 63° | — | — |
| 1974coldest | 64° | 45° | 54° | — | — |
| 1973 | 77° | 55° | 66° | — | — |
| 1972 | 67° | 53° | 60° | 0.03" | — |
| 1971 | 89° | 54° | 71° | — | — |
55 years of data from EL TORO MCAS