October is close to Longmont's year-round average, with average highs near 18.5°C and lows around 3.3°C (mean 10.9°C). It is about average for rainfall, averaging 31 mm of rainfall and 47% relative humidity across the period.
October is close to Longmont's year-round average. Across 45 years of records, the warmest October in Longmont was 2024 — when the month averaged 15.5°C — while the coldest was 2009 at 6°C. Typical October days reach 18.5°C with nights near 3.3°C. The long-term trend is warming, about 0.4°C per decade.
October is about average for rainfall in Longmont, averaging 31 mm of rainfall. The wettest October on record was 1984 with 97 mm, while the driest was 1988 at 6 mm.
Relative humidity in Longmont during October averages 47%. The most humid October was 1984 at 64%, and the least humid was 2003 at 36%.
October receives about 3.7 kWh/m²/day of solar energy in Longmont. The sunniest October was 2003 at 4.1 kWh/m²/day, and the cloudiest was 1984 at 3.
Average wind speed in Longmont during October is 2.2 m/s. The windiest October was 1997 at 2.7 m/s, while the calmest were 1998, 2000 and 2002, among others at 1.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 10.2°C | 10.8°C | 10.7°C | 11.0°C | 12.5°C | +2.3°C |
| Avg High | 17.6°C | 18.5°C | 18.2°C | 18.5°C | 20.3°C | +2.7°C |
| Avg Low | 2.8°C | 3.1°C | 3.1°C | 3.4°C | 4.7°C | +1.9°C |
| Avg Rain | 36 mm | 31 mm | 34 mm | 33 mm | 14 mm | -21 mm |
October temperatures in Longmont have risen by about 3.2°C between 1981–1985 and 2021–2025.
October has ranged from a record low of -14.1°C (2019) to a record high of 31.3°C (2024).
Rainfall in October is about average for rainfall, averaging 31 mm, with a wettest year of 97 mm.
A good time to visit Longmont
October is a good time to visit Longmont, with days averaging 18.5°C and nights around 3.3°C (mean 10.9°C, close to Longmont's yearly average) and moderate rainfall. August and July are marginally more temperate, but October still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 20.8°C | 13.0°C | 5.1°C | 30.3°C | -4.3°C | 15 mm | 44% | 2.1 m/s | 3.8 |
| 2024 🔥 | 23.4°C | 15.5°C | 7.5°C | 31.3°C | -2.9°C | 8 mm | 37% | 2.1 m/s | 3.9 |
| 2023 | 19.5°C | 11.8°C | 4.0°C | 28.6°C | -9.7°C | 21 mm | 45% | 2 m/s | 4 |
| 2022 | 19.3°C | 11.9°C | 4.4°C | 25.6°C | -2.9°C | 15 mm | 43% | 2 m/s | 4 |
| 2021 | 19.7°C | 12.0°C | 4.2°C | 27.7°C | -3.1°C | 13 mm | 43% | 2.1 m/s | 3.7 |
| 2020 | 19.1°C | 11.0°C | 2.8°C | 29.7°C | -13.8°C | 15 mm | 37% | 2.2 m/s | 3.9 |
| 2019 | 15.2°C | 7.2°C | -0.9°C | 27.7°C | -14.1°C | 34 mm | 43% | 2.4 m/s | 3.9 |
| 2018 | 16.3°C | 9.5°C | 2.6°C | 28.8°C | -8.6°C | 39 mm | 56% | 2.1 m/s | 3.3 |
| 2017 | 18.1°C | 10.0°C | 1.9°C | 27.2°C | -5.8°C | 36 mm | 47% | 2.5 m/s | 3.7 |
| 2016 | 22.6°C | 14.5°C | 6.3°C | 27.9°C | -2.0°C | 12 mm | 37% | 2.1 m/s | 3.8 |
| 2015 | 20.8°C | 13.6°C | 6.5°C | 29.5°C | -1.3°C | 47 mm | 51% | 2 m/s | 3.5 |
| 2014 | 20.3°C | 12.8°C | 5.2°C | 27.7°C | -0.7°C | 26 mm | 47% | 2 m/s | 3.9 |
| 2013 | 15.3°C | 8.4°C | 1.4°C | 24.5°C | -3.7°C | 32 mm | 58% | 2.1 m/s | 3.6 |
| 2012 | 18.1°C | 10.1°C | 2.2°C | 27.8°C | -6.7°C | 23 mm | 47% | 2.4 m/s | 3.7 |
| 2011 | 18.6°C | 10.9°C | 3.3°C | 28.7°C | -10.7°C | 44 mm | 46% | 2.3 m/s | 3.8 |
| 2010 | 19.7°C | 12.7°C | 5.6°C | 27.9°C | -3.2°C | 32 mm | 46% | 2.3 m/s | 3.6 |
| 2009 ❄️ | 13.0°C | 6.0°C | -1.0°C | 26.9°C | -8.3°C | 58 mm | 60% | 2.3 m/s | 3.1 |
| 2008 | 19.3°C | 11.5°C | 3.7°C | 26.1°C | -4.4°C | 23 mm | 44% | 2.3 m/s | 3.9 |
| 2007 | 19.9°C | 11.8°C | 3.8°C | 28.2°C | -5.1°C | 38 mm | 46% | 2.4 m/s | 3.9 |
| 2006 | 16.9°C | 9.7°C | 2.5°C | 28.0°C | -6.8°C | 52 mm | 53% | 2.5 m/s | 3.1 |
| 2005 | 19.0°C | 11.5°C | 4.0°C | 30.5°C | -3.2°C | 52 mm | 51% | 2.1 m/s | 3.7 |
| 2004 | 18.1°C | 11.3°C | 4.4°C | 24.1°C | -1.0°C | 55 mm | 55% | 2.1 m/s | 3.5 |
| 2003 | 21.9°C | 13.9°C | 5.9°C | 29.5°C | -5.6°C | 6 mm | 36% | 2.4 m/s | 4.1 |
| 2002 | 15.4°C | 8.0°C | 0.5°C | 25.5°C | -9.9°C | 31 mm | 51% | 1.9 m/s | 3.7 |
| 2001 | 19.8°C | 11.9°C | 3.9°C | 28.3°C | -3.7°C | 10 mm | 37% | 2.3 m/s | 3.6 |
| 2000 | 18.3°C | 10.9°C | 3.4°C | 28.6°C | -4.0°C | 16 mm | 50% | 1.9 m/s | 3.9 |
| 1999 | 20.4°C | 11.8°C | 3.3°C | 27.6°C | -5.7°C | 16 mm | 40% | 2.2 m/s | 4 |
| 1998 | 17.4°C | 10.6°C | 3.7°C | 26.3°C | -0.6°C | 45 mm | 54% | 1.9 m/s | 3.5 |
| 1997 | 18.2°C | 10.5°C | 2.8°C | 30.0°C | -13.1°C | 56 mm | 49% | 2.7 m/s | 3.9 |
| 1996 | 18.2°C | 10.8°C | 3.4°C | 29.0°C | -4.3°C | 21 mm | 46% | 2.3 m/s | 3.9 |
| 1995 | 18.4°C | 10.4°C | 2.4°C | 27.0°C | -3.1°C | 21 mm | 41% | 2.2 m/s | 4 |
| 1994 | 17.7°C | 10.4°C | 3.2°C | 24.4°C | -3.2°C | 35 mm | 50% | 2.1 m/s | 3.7 |
| 1993 | 16.2°C | 9.0°C | 1.9°C | 27.9°C | -10.8°C | 56 mm | 52% | 1.9 m/s | 3.4 |
| 1992 | 20.2°C | 12.6°C | 5.0°C | 28.0°C | -3.5°C | 16 mm | 43% | 2 m/s | 3.6 |
| 1991 | 19.1°C | 11.0°C | 2.9°C | 28.7°C | -10.8°C | 18 mm | 41% | 2.2 m/s | 4 |
| 1990 | 19.2°C | 10.9°C | 2.6°C | 28.4°C | -5.0°C | 28 mm | 44% | 2.5 m/s | 3.6 |
| 1989 | 18.6°C | 10.8°C | 3.0°C | 27.8°C | -5.4°C | 22 mm | 41% | 2.4 m/s | 3.7 |
| 1988 | 20.6°C | 12.9°C | 5.1°C | 25.7°C | -0.8°C | 6 mm | 43% | 2.1 m/s | 3.6 |
| 1987 | 19.5°C | 11.4°C | 3.2°C | 28.4°C | -4.6°C | 29 mm | 44% | 2.1 m/s | 3.9 |
| 1986 | 15.8°C | 8.9°C | 2.1°C | 23.6°C | -8.7°C | 63 mm | 57% | 2.2 m/s | 3.5 |
| 1985 | 17.5°C | 9.9°C | 2.3°C | 24.6°C | -2.3°C | 34 mm | 50% | 2.2 m/s | 3.9 |
| 1984 🌧️ | 13.1°C | 6.9°C | 0.7°C | 23.4°C | -7.6°C | 97 mm | 64% | 2.1 m/s | 3 |
| 1983 | 19.2°C | 11.6°C | 4.1°C | 24.8°C | -2.1°C | 12 mm | 45% | 2 m/s | — |
| 1982 | 16.9°C | 9.4°C | 1.8°C | 25.2°C | -3.1°C | 28 mm | 47% | 2.2 m/s | — |
| 1981 | 17.6°C | 10.1°C | 2.6°C | 26.9°C | -5.9°C | 31 mm | 51% | 2 m/s | — |
Actual recorded October data for each year, 1981–2025 — sourced from NASA POWER.
The average high in October is around 18.5°C with lows near 3.3°C (mean 10.9°C), based on 45 years of NASA POWER data.
October averages 31 mm of rainfall in Longmont, about average for rainfall. The wettest on record was 97 mm in 1984.
The hottest October reached 31.3°C in 2024. The coldest dipped to -14.1°C in 2019.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average October temperatures have risen by about 3.2°C. Daytime highs moved from 16.9°C to 20.5°C and overnight lows from 2.3°C to 5°C over the same span.
October is close to Longmont's year-round average and about average for rainfall, so plan for around 18.5°C daytime highs and 3.3°C at night.
Not quite — October is the 7th coolest month in Longmont, averaging 10.9°C.
For October in Longmont, pack warm layers and a jacket for chilly mornings, with typical highs of 18.5°C and lows of 3.3°C.
Relative humidity in October averages 47% — relatively dry.
Average wind speed in October is 2.2 m/s. The windiest October on record averaged 2.7 m/s (1997).
The wettest October on record was 1984 with 97 mm. On average, October sees 31 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Longmont behaves each October, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for October specifically, along with year-by-year records and how the month has changed over the decades.
