Weather on April 21
Sunnyvale, CA
55 Years of Data
Avg High
70°F
Avg Low
50°F
Warmest
2009
75°F avg
Coldest
2010
50°F avg
About This Date
April 21st in Sunnyvale, CA typically brings pleasant spring weather, with average highs around 70°F and lows near 50°F. Over 55 years of records, the warmest April 21st was in 2009 (75°F average), while the coldest was 2010 (50°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 16% of April 21st dates historically, with the wettest April 21st recording 0.84" of rain. The last decade has been 2.8°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.8°F warmer on this date compared to 20-30 years ago.
Planning for April 21st in Sunnyvale, CA? Great weather for outdoor activities.
Warming Trend
0.9°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 73° | 50° | 62° | — | — |
| 2024 | 81° | 50° | 65° | — | — |
| 2023 | 77° | 50° | 64° | — | — |
| 2022 | 66° | 53° | 60° | 0.23" | — |
| 2021 | 69° | 48° | 59° | — | — |
| 2020 | 70° | 52° | 61° | — | — |
| 2019 | 69° | 47° | 58° | — | — |
| 2018 | 79° | 48° | 63° | — | — |
| 2017 | 77° | 51° | 64° | — | — |
| 2016 | 76° | 58° | 67° | — | — |
| 2015 | 67° | 54° | 60° | — | — |
| 2014 | 71° | 51° | 61° | — | — |
| 2013 | 82° | 51° | 67° | — | — |
| 2012 | 86° | 58° | 72° | — | — |
| 2011 | 65° | 51° | 58° | 0.03" | — |
| 2010coldest | 54° | 46° | 50° | 0.84" | — |
| 2009warmest | 90° | 60° | 75° | — | — |
| 2008 | 59° | 42° | 51° | — | — |
| 2007 | 61° | 43° | 52° | 0.38" | — |
| 2006 | 67° | 51° | 59° | — | — |
| 2005 | 75° | 46° | 61° | — | — |
| 2004 | 66° | 49° | 57° | — | — |
| 2003 | 58° | 49° | 53° | 0.3" | — |
| 2002 | 71° | 48° | 60° | — | — |
| 2001 | 65° | 39° | 52° | — | — |
| 2000 | 67° | 51° | 59° | — | — |
| 1999 | 65° | 48° | 56° | — | — |
| 1998 | 89° | 51° | 70° | — | — |
| 1997 | 78° | 61° | 69° | — | — |
| 1996 | 71° | 44° | 58° | — | — |
| 1995 | 70° | 41° | 55° | — | — |
| 1994 | 68° | 51° | 60° | — | — |
| 1993 | 70° | 54° | 62° | — | — |
| 1992 | 68° | 53° | 61° | — | — |
| 1991 | 69° | 55° | 62° | — | — |
| 1990 | 66° | 54° | 60° | — | — |
| 1989 | 67° | 53° | 60° | 0.2" | — |
| 1988 | 66° | 51° | 59° | — | — |
| 1987 | 89° | 54° | 71° | — | — |
| 1986 | 80° | 56° | 68° | 0.43" | — |
| 1985 | 63° | 49° | 56° | 0.05" | — |
| 1984 | 75° | 47° | 61° | — | — |
| 1983 | 59° | 53° | 56° | — | — |
| 1982 | 82° | 54° | 68° | — | — |
| 1981 | 70° | 48° | 59° | — | — |
| 1980 | 60° | 47° | 53° | 0.23" | — |
| 1979 | 68° | 46° | 57° | — | — |
| 1978 | 65° | 42° | 53° | — | — |
| 1977 | 69° | 42° | 56° | — | — |
| 1976 | 69° | 48° | 59° | — | — |
| 1975 | 60° | 47° | 53° | — | — |
| 1974 | 70° | 51° | 60° | — | — |
| 1973 | 75° | 46° | 61° | — | — |
| 1972 | 66° | 44° | 55° | — | — |
| 1971 | 59° | 44° | 52° | — | — |
55 years of data from MOFFETT FED AIRFIELD