Weather on September 27
Longmont, CO
55 Years of Data
Avg High
77°F
Avg Low
42°F
Warmest
2009
71°F avg
Coldest
1996
35°F avg
About This Date
September 27th in Longmont, CO typically brings pleasant fall weather, with average highs around 77°F and lows near 42°F — a 35°F daily swing. Over 55 years of records, the warmest September 27th was in 2009 (71°F average), while the coldest was 1996 (35°F) — a 36°F range across recorded history. Rain or other precipitation has occurred on about 13% of September 27th dates historically, with the wettest September 27th recording 1.19" of rain. The last decade has been 5.6°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.6°F warmer on this date compared to 20-30 years ago.
Planning for September 27th in Longmont, CO? Great weather for outdoor activities.
Warming Trend
1.2°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 84° | 43° | 63° | — | — |
| 2024 | 91° | 51° | 71° | — | — |
| 2023 | 81° | 44° | 62° | — | — |
| 2022 | 81° | 45° | 63° | — | — |
| 2021 | 87° | 48° | 68° | — | — |
| 2020 | 83° | 49° | 66° | — | — |
| 2019 | 82° | 42° | 62° | — | — |
| 2018 | 71° | 39° | 55° | — | — |
| 2017 | 55° | 41° | 48° | — | — |
| 2016 | 82° | 43° | 62° | — | — |
| 2015 | 89° | 52° | 70° | — | — |
| 2014 | 85° | 52° | 68° | — | — |
| 2013 | 59° | 44° | 52° | 1.19" | — |
| 2012 | 67° | 43° | 55° | 0.33" | — |
| 2011 | 82° | 50° | 66° | — | — |
| 2010 | 83° | 55° | 69° | — | — |
| 2009warmest | 84° | 57° | 71° | — | — |
| 2008 | 74° | 47° | 60° | — | — |
| 2007 | 73° | 41° | 57° | — | — |
| 2006 | 72° | 43° | 57° | — | — |
| 2005 | 86° | 50° | 68° | 0.05" | — |
| 2004 | 79° | 43° | 61° | — | — |
| 2003 | 79° | 40° | 59° | — | — |
| 2002 | 64° | 33° | 49° | — | — |
| 2001 | 92° | 40° | 66° | — | — |
| 2000 | 73° | 29° | 51° | — | — |
| 1999 | 64° | 32° | 48° | 0.05" | — |
| 1998 | 84° | 46° | 65° | — | — |
| 1997 | 82° | 43° | 62° | — | — |
| 1996coldest | 47° | 23° | 35° | 0.66" | — |
| 1995 | 77° | 36° | 56° | — | — |
| 1994 | 87° | 42° | 65° | — | — |
| 1993 | 68° | 33° | 51° | 0.05" | — |
| 1992 | 73° | 36° | 54° | — | — |
| 1991 | 81° | 37° | 59° | — | — |
| 1990 | 87° | 45° | 66° | — | — |
| 1989 | 83° | 44° | 63° | — | — |
| 1988 | 82° | 38° | 60° | — | — |
| 1987 | 88° | 48° | 68° | — | — |
| 1986 | 69° | 35° | 52° | — | — |
| 1985 | 68° | 43° | 55° | — | — |
| 1984 | 57° | 34° | 45° | — | — |
| 1983 | 87° | 45° | 66° | — | — |
| 1982 | 76° | 47° | 61° | — | — |
| 1981 | 77° | 40° | 58° | — | — |
| 1980 | 79° | 42° | 60° | — | — |
| 1979 | 83° | 47° | 65° | — | — |
| 1978 | 85° | 45° | 65° | — | — |
| 1977 | 84° | 41° | 63° | — | — |
| 1976 | 58° | 41° | 49° | 0.53" | — |
| 1975 | 87° | 39° | 63° | — | — |
| 1974 | 87° | 45° | 66° | — | — |
| 1973 | 60° | 30° | 45° | — | — |
| 1972 | 63° | 36° | 49° | — | — |
| 1971 | 79° | 41° | 60° | — | — |
55 years of data from LONGMONT 2 ESE