Climate averages 1991–2020
Greeley weather
in December.
A cold, very dry month: the coolest and one of the driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a cold month in Greeley: daytime highs average 4.9°C and nights cool to about -6.8°C. By daytime temperature it is the coolest month of the year.
Expect about 11 mm of rain on roughly 3 days, which makes December a very dry month (one of the driest months of the year). Daylight, from sunrise to sunset, lasts about 9 h 21 min on an average December day.
The nearest other city in this atlas is Loveland (31 km away). In December its highs average 4.2°C, 0.7°C cooler than Greeley, with 16 mm of rain.
Among the 498 cities listed in the United States, Greeley ranks joint 364th of 498 for the warmest December highs and 2nd of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; Greeley is 5.6°C cooler than that mean.
From December to January, average highs rise by 0.5°C to 5.4°C, and monthly rainfall stays at 11 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Greeley climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 5.4°C-7.4°C | -7.4°C | 11 | 2.9 | 9.610 h |
| February | 7.4°C-6.3°C | -6.3°C | 11 | 3.4 | 10.611 h |
| March | 12.9°C-2.3°C | -2.3°C | 29 | 5.4 | 11.912 h |
| April | 16.9°C2.2°C | 2.2°C | 49 | 8.5 | 13.313 h |
| May | 22.0°C7.7°C | 7.7°C | 67 | 9.7 | 14.414 h |
| June | 28.3°C13.3°C | 13.3°C | 40 | 7.3 | 15.015 h |
| July | 31.9°C17.1°C | 17.1°C | 36 | 7.4 | 14.815 h |
| August | 30.5°C16.0°C | 16.0°C | 31 | 6.6 | 13.814 h |
| September | 26.0°C11.3°C | 11.3°C | 27 | 4.6 | 12.513 h |
| October | 17.9°C3.9°C | 3.9°C | 30 | 5.1 | 11.211 h |
| November | 10.4°C-2.7°C | -2.7°C | 16 | 3.8 | 10.010 h |
| December, selected | 4.9°C-6.8°C | -6.8°C | 11 | 2.9 | 9.39 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
- Loveland in DecemberUnited States · 31 kmHigh 4.2°C · Low -8.4°C · 16 mm rain
- Fort Collins in DecemberUnited States · 36 kmHigh 4.2°C · Low -7.8°C · 16 mm rain
- Longmont in DecemberUnited States · 44 kmHigh 4.2°C · Low -8.1°C · 18 mm rain
- Thornton in DecemberUnited States · 66 kmHigh 4.0°C · Low -9.7°C · 21 mm rain
- Boulder in DecemberUnited States · 66 kmHigh 4.0°C · Low -8.8°C · 23 mm rain
- Westminster (Colorado), United States in DecemberUnited States · 71 kmHigh 4.2°C · Low -9.8°C · 21 mm rain
- Arvada in DecemberUnited States · 76 kmHigh 4.4°C · Low -9.7°C · 21 mm rain
- Aurora (Colorado), United States in DecemberUnited States · 78 kmHigh 5.0°C · Low -8.0°C · 14 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Greeley) is explained once on the Greeley year overview and on the Sources, method and limits page.