Weather on March 21
Plano, TX
55 Years of Data
Avg High
70°F
Avg Low
46°F
Warmest
2026
77°F avg
Coldest
2010
36°F avg
About This Date
March 21st in Plano, TX typically brings pleasant spring weather, with average highs around 70°F and lows near 46°F. Over 56 years of records, the warmest March 21st was in 2026 (77°F average), while the coldest was 2010 (36°F) — a 41°F range across recorded history. Rain or other precipitation has occurred on about 25% of March 21st dates historically, with the wettest March 21st recording 5.08" of rain. The last decade has been 4.3°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.3°F warmer on this date compared to 20-30 years ago.
Planning for March 21st in Plano, TX? Great weather for outdoor activities.
Warming Trend
0.6°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2026warmest | 91° | 63° | 77° | — | — |
| 2025 | 75° | 46° | 61° | — | — |
| 2024 | 65° | 52° | 58° | 4.57" | — |
| 2023 | 65° | 48° | 56° | 0.23" | — |
| 2022 | 71° | 55° | 63° | 5.08" | — |
| 2021 | 67° | 44° | 55° | — | — |
| 2020 | 59° | 39° | 49° | 0.38" | — |
| 2019 | 75° | 48° | 62° | — | — |
| 2018 | 71° | 40° | 55° | — | — |
| 2017 | 83° | 61° | 72° | — | — |
| 2016 | 64° | 33° | 49° | — | — |
| 2015 | 62° | 52° | 57° | 0.13" | — |
| 2014 | 79° | 51° | 65° | — | — |
| 2013 | 69° | 51° | 60° | — | — |
| 2012 | 65° | 51° | 58° | — | — |
| 2011 | 81° | 63° | 72° | — | — |
| 2010coldest | 43° | 29° | 36° | 0.74" | — |
| 2009 | 76° | 55° | 65° | — | — |
| 2008 | 74° | 49° | 61° | — | — |
| 2007 | 76° | 65° | 70° | 0.03" | — |
| 2006 | 55° | 38° | 46° | — | — |
| 2005 | 77° | 57° | 67° | 0.51" | — |
| 2004 | 70° | 49° | 59° | — | — |
| 2003 | 56° | 45° | 50° | — | — |
| 2002 | 62° | 34° | 48° | — | — |
| 2001 | 62° | 38° | 50° | — | — |
| 2000 | 74° | 41° | 57° | — | — |
| 1999 | 68° | 38° | 53° | — | — |
| 1998 | 60° | 33° | 47° | — | — |
| 1997 | 88° | 48° | 68° | — | — |
| 1996 | 67° | — | — | — | — |
| 1995 | 81° | 56° | 68° | — | — |
| 1994 | 80° | 52° | 66° | — | — |
| 1993 | 64° | 47° | 55° | — | — |
| 1992 | 63° | 40° | 51° | — | — |
| 1991 | 80° | 36° | 58° | — | — |
| 1990 | 73° | 41° | 57° | — | — |
| 1989 | 64° | 33° | 49° | 0.64" | — |
| 1988 | 81° | 28° | 54° | — | — |
| 1987 | 78° | 52° | 65° | — | — |
| 1986 | 57° | 29° | 43° | — | — |
| 1985 | 66° | 49° | 57° | 0.25" | — |
| 1984 | 72° | 39° | 55° | — | — |
| 1983 | 52° | 32° | 42° | — | — |
| 1982 | 76° | 46° | 61° | — | — |
| 1981 | 76° | 55° | 65° | — | — |
| 1980 | 70° | 46° | 58° | — | — |
| 1979 | 76° | 62° | 69° | 0.64" | — |
| 1978 | 79° | 57° | 68° | 0.41" | — |
| 1977 | 66° | 38° | 52° | — | — |
| 1976 | 71° | 41° | 56° | — | — |
| 1975 | 80° | 60° | 70° | — | — |
| 1974 | 50° | 30° | 40° | 0.79" | — |
| 1973 | 59° | 40° | 49° | — | — |
| 1972 | 78° | 52° | 65° | 0.38" | — |
| 1971 | 78° | 45° | 61° | — | — |
56 years of data from RICHARDSON