Northglenn, CO climate
Northglenn has chilly, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 89°, a January night drops to 19°, and about 74 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeRight about normal today. The forecast high is 72°, and a typical Oct 1 in Northglenn peaks around 72°.Live forecast: National Weather Service · Normal: NOAA 1991–2020
What a year in Northglenn feels like
Winter
Spring
Summer
Fall
Northglenn weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 46° | 19° | 0.4" | 9.0" | 5 | 24° – 39° |
| February | 47° | 21° | 0.5" | 12.4" | 6 | 29° – 42° |
| March | 56° | 28° | 1.0" | 16.3" | 7 | 36° – 49° |
| April | 62° | 34° | 1.8" | 8.1" | 9 | 42° – 54° |
| May | 71° | 44° | 2.4" | 2.6" | 11 | 52° – 62° |
| June | 83° | 53° | 1.5" | 0 | 8 | 64° – 73° |
| July | 89° | 59° | 1.8" | 0 | 9 | 70° – 77° |
| August | 87° | 57° | 1.5" | 0 | 9 | 68° – 75° |
| September | 79° | 48° | 1.2" | 0 | 7 | 59° – 68° |
| October | 66° | 36° | 1.0" | 5.2" | 6 | 43° – 57° |
| November | 54° | 27° | 0.7" | 8.4" | 5 | 32° – 47° |
| December | 46° | 19° | 0.5" | 11.9" | 5 | 25° – 36° |
| Year | 66° | 37° | 14.3" | 73.9" | 87 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Northglenn
Northglenn gets 14 inches of rain and melted snow a year. May is the wettest month and January the driest. Rain or snow falls on about 87 days a year.
About 160 frost-free days a year
In half of years the last 32° night comes by May 2 and the first one by October 11. That leaves about 160 frost-free days for gardens, shorter than 71% of U.S. towns.
Heating and cooling a home in Northglenn
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Northglenn, 86% of that work is heating and 14% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Northglenn and its neighbors
Northglenn borders 3 towns with climate data. January nights across them vary by 1.0°. Thornton has both the coldest January nights (18°) and the hottest July afternoons (90°). Northglenn’s January low is 19° and its July high 89°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Northglenn compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Northglenn averaged 1.5° warmer than the 1900s. The biggest change is in March (+3.5°). The shift is larger than in 72% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Northglenn’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from 24° to 39°. July is the most reliable, staying within 8°.
Common questions about Northglenn’s climate
What is the coldest month in Northglenn?
December, with a typical high of 46° and a low of 19°.
What is the hottest month in Northglenn?
July, with a typical high of 89° and a low of 59°. About 53 days a year reach 90°.
How much snow does Northglenn get?
About 74 inches in a normal winter, most of it in March.
When is the first frost in Northglenn?
In half of years the first 32° night comes by October 11, and the last spring frost by May 2.
What is the rainiest month in Northglenn?
May, with 2.4 inches of rain and melted snow. The year totals 14 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Northglenn itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Broomfield 1.1 Ne, CO (6 mi, snow) and Northglenn, CO (2 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.