Historical Weather in Longmont, CO

See 55+ years of weather history for any date in Longmont going back to 1970.

Part of Colorado weather history

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Searching weather history for Longmont, CO

Today in Longmont Weather HistorySee records, averages, and 55+ years of data for today's date

Monthly Climate Averages

Historical temperature and precipitation averages for Longmont, CO, based on 55+ years of weather data.

Warmest MonthJulyAvg High: 88°F / Low: 57°F
Coldest MonthJanuaryAvg High: 44°F / Low: 18°F
Jan
44°/ 18°
💧 3.3"
❄️ 2.1"
Feb
47°/ 20°
💧 3.5"
❄️ 2.1"
Mar
55°/ 28°
💧 6.2"
❄️ 2.6"
Apr
63°/ 34°
💧 7.4"
❄️ 2.9"
May
71°/ 43°
💧 6.7"
❄️ 2.5"
Jun
83°/ 52°
💧 5.4"
Jul
88°/ 57°
💧 4.3"
Aug
87°/ 56°
💧 4.2"
Sep
79°/ 47°
💧 5.9"
❄️ 3.1"
Oct
66°/ 36°
💧 5.0"
❄️ 2.8"
Nov
53°/ 26°
💧 5.0"
❄️ 2.7"
Dec
46°/ 20°
💧 4.0"
❄️ 2.5"

Temperatures in Fahrenheit. Precipitation and snowfall in inches.

Longmont Temperature Records

  • Record High: The hottest temperature ever recorded in Longmont, CO is 106°F, set on July 7, 1973.
  • Record Low: The coldest temperature ever recorded in Longmont, CO is -31°F, set on December 22, 1990.
  • Data Coverage: Based on 57 years of data from NOAA weather station: LONGMONT 2 ESE.

All-Time Record High

106°F
July 7, 1973

All-Time Record Low

-31°F
December 22, 1990

Monthly Temperature Records in Longmont

MonthRecord HighRecord Low
January75°F(1982)-30°F(1984)
February77°F(1982)-28°F(1989)
March85°F(1997)-14°F(1989)
April91°F(2022)-7°F(1975)
May100°F(2003)10°F(2013)
June106°F(1994)18°F(2014)
July106°F(1973)35°F(2024)
August104°F(1995)37°F(1992)
September103°F(2019)15°F(1985)
October90°F(1980)-8°F(2020)
November82°F(2025)-16°F(1993)
December77°F(2025)-31°F(1990)
Colorado State RecordsSee all-time records for the entire state
Longmont Snow RecordsSee the top 10 snowiest days ever recorded