Weather on September 16
Longmont, CO
55 Years of Data
Avg High
79°F
Avg Low
45°F
Warmest
2018
73°F avg
Coldest
1973
42°F avg
About This Date
September 16th in Longmont, CO typically brings pleasant fall weather, with average highs around 79°F and lows near 45°F — a 34°F daily swing. Over 55 years of records, the warmest September 16th was in 2018 (73°F average), while the coldest was 1973 (42°F) — a 31°F range across recorded history. Rain or other precipitation has occurred on about 20% of September 16th dates historically, with the wettest September 16th recording 1.24" of rain. The last decade has been 2.7°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.7°F warmer on this date compared to 20-30 years ago.
Planning for September 16th in Longmont, CO? Great weather for outdoor activities.
Warming Trend
1.8°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 86° | 51° | 69° | — | — |
| 2024 | 87° | 50° | 69° | 0.1" | — |
| 2023 | 66° | 43° | 54° | — | — |
| 2022 | 77° | 50° | 64° | 0.03" | — |
| 2021 | 87° | 50° | 69° | — | — |
| 2020 | 88° | 48° | 68° | — | — |
| 2019 | 85° | 49° | 67° | — | — |
| 2018warmest | 93° | 53° | 73° | — | — |
| 2017 | 83° | 48° | 65° | 0.51" | — |
| 2016 | 73° | 39° | 56° | — | — |
| 2015 | 88° | 54° | 71° | — | — |
| 2014 | 85° | 47° | 66° | — | — |
| 2013 | 72° | 52° | 62° | 1.24" | — |
| 2012 | 86° | 53° | 70° | — | — |
| 2011 | 74° | 41° | 57° | — | — |
| 2010 | 87° | 47° | 67° | — | — |
| 2009 | 79° | 54° | 66° | — | — |
| 2008 | 79° | 44° | 61° | — | — |
| 2007 | 87° | 46° | 67° | — | — |
| 2006 | 67° | 42° | 54° | — | — |
| 2005 | 81° | 47° | 64° | — | — |
| 2004 | 74° | 41° | 57° | — | — |
| 2003 | 85° | 46° | 65° | — | — |
| 2002 | 87° | 40° | 63° | — | — |
| 2001 | 68° | 50° | 59° | 0.13" | — |
| 2000 | 94° | 51° | 72° | — | — |
| 1999 | 76° | 34° | 55° | — | — |
| 1998 | 82° | 44° | 63° | — | — |
| 1997 | 90° | 48° | 69° | — | — |
| 1996 | 74° | 47° | 60° | — | — |
| 1995 | 92° | 42° | 67° | — | — |
| 1994 | 79° | 44° | 61° | — | — |
| 1993 | 81° | 42° | 61° | — | — |
| 1992 | 91° | — | — | — | — |
| 1991 | 70° | 37° | 53° | — | — |
| 1990 | 83° | 42° | 62° | — | — |
| 1989 | 82° | 38° | 60° | — | — |
| 1988 | 72° | 37° | 54° | — | — |
| 1987 | 70° | 44° | 57° | — | — |
| 1986 | 73° | 54° | 63° | — | — |
| 1985 | 85° | 47° | 66° | — | — |
| 1984 | 59° | 40° | 49° | — | — |
| 1983 | 76° | 41° | 58° | — | — |
| 1982 | 63° | 42° | 52° | 0.05" | — |
| 1981 | 79° | 49° | 64° | 0.05" | — |
| 1980 | 87° | 47° | 67° | 0.05" | — |
| 1979 | 77° | 40° | 58° | — | — |
| 1978 | 88° | 52° | 70° | — | — |
| 1977 | 83° | 47° | 65° | — | — |
| 1976 | 68° | 43° | 55° | 0.46" | — |
| 1975 | 84° | 47° | 65° | — | — |
| 1974 | 70° | 45° | 57° | — | — |
| 1973coldest | 46° | 38° | 42° | 0.15" | — |
| 1972 | 81° | 41° | 61° | — | — |
| 1971 | 63° | 39° | 51° | 0.18" | — |
55 years of data from LONGMONT 2 ESE