Weather on March 20
Ontario, CA
55 Years of Data
Avg High
71°F
Avg Low
48°F
Warmest
2026
82°F avg
Coldest
1982
47°F avg
About This Date
March 20th in Ontario, CA typically brings pleasant spring weather, with average highs around 71°F and lows near 48°F. Over 42 years of records, the warmest March 20th was in 2026 (82°F average), while the coldest was 1982 (47°F) — a 35°F range across recorded history. Rain or other precipitation has occurred on about 24% of March 20th dates historically, with the wettest March 20th recording 2.59" of rain. The last decade has been 1.4°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.4°F warmer on this date compared to 20-30 years ago.
Planning for March 20th in Ontario, CA? Great weather for outdoor activities.
Warming Trend
1.8°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2026warmest | 100° | 65° | 82° | — | — |
| 2025 | 73° | 50° | 62° | — | — |
| 2024 | 75° | 52° | 63° | — | — |
| 2023 | 61° | 50° | 55° | 0.43" | — |
| 2022 | 70° | 50° | 60° | — | — |
| 2021 | 68° | 51° | 60° | — | — |
| 2020 | 63° | 48° | 55° | 0.05" | — |
| 2019 | 67° | 53° | 60° | 0.13" | — |
| 2018 | 76° | 53° | 64° | — | — |
| 2017 | 71° | 52° | 61° | — | — |
| 2016 | 79° | 50° | 64° | — | — |
| 2015 | 85° | 53° | 69° | — | — |
| 2014 | 80° | 53° | 67° | — | — |
| 2013 | 73° | 52° | 62° | — | — |
| 2012 | 69° | 42° | 56° | — | — |
| 2011 | 56° | 47° | 51° | 0.58" | — |
| 2010 | 84° | 49° | 66° | — | — |
| 2009 | 74° | 50° | 62° | — | — |
| 2008 | 72° | 47° | 59° | — | — |
| 2007 | 63° | 50° | 56° | — | — |
| 2006 | 58° | 44° | 51° | 0.51" | — |
| 2005 | 65° | 48° | 56° | 0.08" | — |
| 2004 | 91° | 50° | 71° | — | — |
| 2003 | 63° | 45° | 54° | — | — |
| 2002 | 84° | 45° | 64° | — | — |
| 2001 | 84° | 57° | 71° | — | — |
| 2000 | 66° | 51° | 59° | — | — |
| 1999 | 60° | 44° | 52° | 0.03" | — |
| 1984 | 90° | 46° | 68° | — | — |
| 1983 | 59° | 41° | 50° | — | — |
| 1982coldest | 63° | 32° | 47° | — | — |
| 1981 | 59° | 46° | 53° | 2.16" | — |
| 1980 | 69° | 43° | 56° | — | — |
| 1979 | 60° | 41° | 51° | 0.2" | — |
| 1978 | 66° | 49° | 57° | — | — |
| 1977 | 68° | 39° | 54° | — | — |
| 1976 | 75° | 41° | 58° | — | — |
| 1975 | 70° | 44° | 57° | — | — |
| 1974 | 58° | 46° | 52° | — | — |
| 1973 | 55° | 41° | 48° | 2.59" | — |
| 1972 | 72° | 46° | 59° | — | — |
| 1971 | 72° | 40° | 56° | — | — |
42 years of data from ONTARIO INTL AP