Weather on May 9
San Marcos, CA
55 Years of Data
Avg High
75°F
Avg Low
54°F
Warmest
2025
76°F avg
Coldest
1977
56°F avg
About This Date
May 9th in San Marcos, CA typically brings pleasant spring weather, with average highs around 75°F and lows near 54°F. Over 55 years of records, the warmest May 9th was in 2025 (76°F average), while the coldest was 1977 (56°F) — a 20°F range across recorded history. Rain or other precipitation has occurred on about 11% of May 9th dates historically, with the wettest May 9th recording 3.91" of rain. The last decade has been 1.1°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.1°F warmer on this date compared to 20-30 years ago.
Planning for May 9th in San Marcos, CA? Great weather for outdoor activities.
Warming Trend
0.5°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025warmest | 94° | 58° | 76° | — | — |
| 2024 | 78° | 57° | 68° | — | — |
| 2023 | 72° | 55° | 63° | — | — |
| 2022 | 73° | 54° | 63° | — | — |
| 2021 | 75° | 56° | 65° | — | — |
| 2020 | 80° | 62° | 71° | — | — |
| 2019 | 63° | 58° | 60° | — | — |
| 2018 | 84° | 58° | 71° | — | — |
| 2017 | 69° | 57° | 63° | — | — |
| 2016 | 71° | 57° | 64° | 0.03" | — |
| 2015 | 67° | 52° | 59° | — | — |
| 2014 | 77° | 53° | 65° | — | — |
| 2013 | 73° | 57° | 65° | — | — |
| 2012 | 80° | 55° | 68° | — | — |
| 2011 | 63° | 54° | 58° | — | — |
| 2010 | 63° | 56° | 59° | — | — |
| 2009 | 66° | 58° | 62° | — | — |
| 2008 | 61° | 56° | 58° | — | — |
| 2007 | 91° | 57° | 74° | — | — |
| 2006 | 66° | 58° | 62° | — | — |
| 2005 | 74° | 52° | 63° | — | — |
| 2004 | 86° | 52° | 69° | — | — |
| 2003 | 65° | 49° | 57° | 0.03" | — |
| 2002 | 77° | 52° | 64° | — | — |
| 2001 | 89° | 58° | 73° | — | — |
| 2000 | 77° | 48° | 63° | — | — |
| 1999 | 72° | 58° | 65° | — | — |
| 1998 | 64° | 57° | 61° | — | — |
| 1997 | 80° | 58° | 69° | — | — |
| 1996 | 81° | 58° | 69° | — | — |
| 1995 | 71° | 52° | 61° | — | — |
| 1994 | 73° | 52° | 62° | 0.18" | — |
| 1993 | 93° | 53° | 73° | — | — |
| 1992 | 73° | 59° | 66° | 0.1" | — |
| 1991 | 66° | 56° | 61° | — | — |
| 1990 | 74° | 52° | 63° | — | — |
| 1989 | 77° | 58° | 67° | — | — |
| 1988 | 76° | 48° | 62° | — | — |
| 1987 | 82° | 58° | 70° | — | — |
| 1986 | 80° | 48° | 64° | — | — |
| 1985 | 66° | 58° | 62° | — | — |
| 1984 | 91° | 56° | 73° | — | — |
| 1983 | 76° | 55° | 65° | — | — |
| 1982 | 63° | 53° | 58° | 0.03" | — |
| 1981 | 92° | 52° | 72° | — | — |
| 1980 | 68° | 49° | 58° | — | — |
| 1979 | 71° | 46° | 59° | — | — |
| 1978 | 85° | 49° | 67° | — | — |
| 1977coldest | 63° | 50° | 56° | 3.91" | — |
| 1976 | 78° | 54° | 66° | — | — |
| 1975 | 79° | 49° | 64° | — | — |
| 1974 | 63° | 55° | 59° | — | — |
| 1973 | 83° | 50° | 66° | — | — |
| 1972 | 73° | 50° | 62° | — | — |
| 1971 | 72° | 44° | 58° | — | — |
55 years of data from ESCONDIDO #2