Historical Weather in Boulder, CO
See 55+ years of weather history for any date in Boulder going back to 1970.
Part of Colorado weather history · Colorado temperature records
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Today in Boulder Weather HistorySee records, averages, and 55+ years of data for today's date
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Monthly Climate Averages
Historical temperature and precipitation averages for Boulder, CO, based on 55+ years of weather data.
Warmest MonthJulyAvg High: 87°F / Low: 58°F
Coldest MonthJanuaryAvg High: 45°F / Low: 21°F
Jan
45°/ 21°
💧 3.4"
❄️ 2.2"
Feb
47°/ 22°
💧 3.7"
❄️ 2.2"
Mar
55°/ 29°
💧 6.2"
❄️ 2.7"
Apr
61°/ 35°
💧 7.7"
❄️ 3.0"
May
69°/ 43°
💧 6.7"
❄️ 3.0"
Jun
81°/ 52°
💧 5.0"
Jul
87°/ 58°
💧 4.2"
Aug
85°/ 57°
💧 3.9"
Sep
77°/ 49°
💧 6.2"
❄️ 3.2"
Oct
65°/ 38°
💧 5.3"
❄️ 3.0"
Nov
53°/ 29°
💧 5.3"
❄️ 2.9"
Dec
46°/ 23°
💧 4.2"
❄️ 2.5"
Temperatures in Fahrenheit. Precipitation and snowfall in inches.
Boulder, CO Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
Avg high Avg low
Boulder, CO Monthly Precipitation
Average rainfall and snowfall per month, in inches.
Rain (in) Snow (in)
Boulder, CO Daily Temperature Calendar
Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.
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Best Time to Visit Boulder, CO
Boulder, CO has no months that meet our "pleasant" threshold — every season has tradeoffs.
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Pleasant (65-82°F, ≤2.5" rain) Mild Less ideal
Boulder Temperature Records
- Record High: The hottest temperature ever recorded in Boulder, CO is 106°F, set on July 7, 1973.
- Record Low: The coldest temperature ever recorded in Boulder, CO is -31°F, set on December 22, 1990.
- Data Coverage: Based on 10 years of data from NOAA weather station: BOULDER MUNI AP.
All-Time Record High
106°F
July 7, 1973
All-Time Record Low
-31°F
December 22, 1990
Monthly Temperature Records in Boulder
| Month | Record High | Record Low |
|---|---|---|
| January | 75°F(1982) | -30°F(1984) |
| February | 77°F(1982) | -28°F(1989) |
| March | 85°F(1997) | -12°F(2002) |
| April | 91°F(2022) | -7°F(1975) |
| May | 100°F(2003) | 11°F(2013) |
| June | 106°F(1994) | 28°F(2008) |
| July | 106°F(1973) | 35°F(1978) |
| August | 104°F(1995) | 27°F(2009) |
| September | 101°F(2020) | 15°F(1985) |
| October | 90°F(1980) | -2°F(2019) |
| November | 82°F(2025) | -16°F(1993) |
| December | 77°F(2025) | -31°F(1990) |
Boulder Snow RecordsSee the top 10 snowiest days ever recorded
→National Parks in Colorado
Holiday Weather in Boulder
Weather Analysis & Trends
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