Weather on October 21
Boise, ID
55 Years of Data
Avg High
64°F
Avg Low
40°F
Warmest
2003
68°F avg
Coldest
1996
37°F avg
About This Date
October 21st in Boise, ID typically brings mild fall weather, with average highs around 64°F and lows near 40°F. Over 55 years of records, the warmest October 21st was in 2003 (68°F average), while the coldest was 1996 (37°F) — a 31°F range across recorded history. Rain or other precipitation has occurred on about 18% of October 21st dates historically, with the wettest October 21st recording 1.65" of rain. The last decade has been 3.6°F warmer on this date compared to 20-30 years ago.
The last decade has been 3.6°F warmer on this date compared to 20-30 years ago.
Planning for October 21st in Boise, ID? Great weather for outdoor activities.
Warming Trend
0.9°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 60° | 38° | 49° | — | — |
| 2024 | 71° | 52° | 61° | — | — |
| 2023 | 79° | 51° | 65° | — | — |
| 2022 | 70° | 48° | 59° | 0.43" | — |
| 2021 | 76° | 52° | 64° | — | — |
| 2020 | 63° | 40° | 51° | — | — |
| 2019 | 56° | 40° | 48° | — | — |
| 2018 | 69° | 44° | 57° | — | — |
| 2017 | 50° | 33° | 42° | 0.41" | — |
| 2016 | 70° | 40° | 55° | — | — |
| 2015 | 66° | 43° | 54° | — | — |
| 2014 | 60° | 46° | 53° | 0.76" | — |
| 2013 | 67° | 39° | 53° | — | — |
| 2012 | 57° | 31° | 44° | — | — |
| 2011 | 67° | 45° | 56° | — | — |
| 2010 | 71° | 43° | 57° | — | — |
| 2009 | 57° | 43° | 50° | — | — |
| 2008 | 53° | 35° | 44° | — | — |
| 2007 | 54° | 37° | 45° | — | — |
| 2006 | 57° | 32° | 45° | — | — |
| 2005 | 66° | 41° | 54° | — | — |
| 2004 | 56° | 38° | 47° | — | — |
| 2003warmest | 84° | 52° | 68° | — | — |
| 2002 | 65° | 46° | 55° | — | — |
| 2001 | 65° | 38° | 51° | — | — |
| 2000 | 51° | 38° | 44° | 0.36" | — |
| 1999 | 71° | 40° | 55° | — | — |
| 1998 | 66° | 37° | 52° | — | — |
| 1997 | 65° | 39° | 52° | — | — |
| 1996coldest | 50° | 23° | 37° | — | — |
| 1995 | 55° | 34° | 44° | — | — |
| 1994 | 65° | 40° | 52° | — | — |
| 1993 | 64° | 39° | 52° | — | — |
| 1992 | 68° | 45° | 56° | — | — |
| 1991 | 76° | 44° | 60° | — | — |
| 1990 | 61° | 36° | 48° | 0.3" | — |
| 1989 | 67° | 51° | 59° | 0.74" | — |
| 1988 | 76° | 45° | 60° | — | — |
| 1987 | 66° | 34° | 50° | — | — |
| 1986 | 65° | 37° | 51° | — | — |
| 1985 | 71° | 34° | 52° | 0.15" | — |
| 1984 | 48° | 28° | 38° | — | — |
| 1983 | 74° | 47° | 60° | — | — |
| 1982 | 71° | 39° | 55° | — | — |
| 1981 | 55° | 31° | 43° | — | — |
| 1980 | 62° | 39° | 51° | — | — |
| 1979 | 53° | 42° | 48° | 0.33" | — |
| 1978 | 62° | 38° | 50° | — | — |
| 1977 | 63° | 35° | 49° | — | — |
| 1976 | 63° | 29° | 46° | — | — |
| 1975 | 66° | 46° | 56° | 1.24" | — |
| 1974 | 44° | 39° | 42° | 1.65" | — |
| 1973 | 72° | 47° | 59° | — | — |
| 1972 | 62° | 46° | 54° | — | — |
| 1971 | 55° | 30° | 43° | — | — |
55 years of data from BOISE AIR TERMINAL