Longmont (CO) monthly weather averages

Average daytime temperature

The bar chart below shows the average monthly peak daytime temperatures at Longmont

Longmont average temperature chart (Celsius) Longmont average temperature chart (Fahrenheit)
Average monthly temperatures in Longmont (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 5.2 7.7 10.7 15.9 20.9 26.3 29.9 28.6 23.7 18.3 10.5 6.3
°F 41.4 45.9 51.2 60.7 69.7 79.4 85.9 83.4 74.6 64.9 50.9 43.4

Please note: these are the average peak daytime temperatures (usually around mid-afternoon) so do not show daytime / night highs and lows. To see the daily range of temperatures have a look at the temperature max / min chart below.

Average rainfall & rainy days

The graph below shows the average rainfall and number of rainy days per month.

Longmont monthly rainfall chart (mm) Longmont monthly rainfall chart (inches)
Average monthly rainfall in Longmont (mm and inches)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
mm 13 14 36 49 74 49 46 34 35 27 24 15
inches 0.5 0.6 1.4 1.9 2.9 1.9 1.8 1.3 1.4 1.1 0.9 0.6
Rainy days 5 6 9 8 11 9 9 9 7 5 6 6

Average annual rainfall in Longmont: 348.367mm (137.2 inches)

Average daily sunshine

The bar chart below shows the average daily sunshine hours in Longmont

Longmont average daily sunshine chart
Average daily sunshine Longmont
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Hrs sunshine 7.4 8.1 8.8 9.9 10.1 11.3 11.3 10.7 9.8 8.6 7 6.8

Day / night temperatures

The graph below shows the daily range of temperatures for each month.

Longmont average minimum / maximum temperatures (Celsius) Longmont average minimum / maximum temperatures (Fahrenheit)
Maximum and minimum daily temperatures in Longmont (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C -9.2 -6.5 -3.6 1.1 6.3 10.9 14.3 13.1 8.2 2.6 -3.5 -7.7
Max °C 5.6 8.1 11 16.3 21.3 26.7 30.3 29 24.1 18.7 10.9 6.7
Min °F 15.4 20.4 25.5 34 43.3 51.6 57.7 55.5 46.7 36.6 25.8 18.2
Max °F 28.8 33.4 38.7 47.7 56.8 65.8 72.1 69.8 61 51.1 38.7 31.1

Sea temperature

The graph below shows the average sea temperature.

Longmont average sea temperature chart (Celsius) Longmont average sea temperature chart (Fahrenheit)
Average sea temperature around Longmont in degrees centigrade and fahrenheit
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 10.4 10.2 10.5 11.2 12.6 14.4 16.6 18.4 17.6 15.3 13 11.3
°F 50.8 50.4 50.9 52.2 54.6 58 61.9 65.1 63.7 59.5 55.4 52.4

Wind speed

The graph below shows the average wind speed.

Longmont average winspeed by month (km/h) Longmont average winspeed by month (mph)
Average wind speed in Longmont (mph and kmh)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
km/h 17 17 18 18 17 16 15 15 15 16 16 17
mph 11 11 11 11 11 10 9 9 9 10 10 11

A monthly average windspeed of over 16km/h or 10mph suggests a location is fairly windy.

Relative humidity

The graph below shows the average relative humidity.

Longmont relative humidity averages
Average relative humidity in Longmont
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
56% 56% 55% 51% 53% 49% 48% 49% 50% 49% 56% 57%

Other monthly averages

UV index Best time to go?

Longmont weather stats

Longmont weather statistics
Hottest month: July 29.9°C 85.8°F
Driest month: January 13mm 0.5ins
Sunniest month: September 9.8hrs
Coldest month: January 5.2°C 41.4°F
Wettest month: May 74mm 2.9ins
Warmest sea: August 18.4°C 65.1°F
Map showing location of Longmont (40.16721, -105.10193) Longmont map pin © Google

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