Climate averages 1991–2020
Highlands Ranch weather
in December.
A cold, fairly 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 Highlands Ranch: daytime highs average 3.8°C and nights cool to about -10.6°C. By daytime temperature it is the coolest month of the year.
Expect about 22 mm of rain on roughly 5 days, which makes December a fairly dry month (one of the driest months of the year). Daylight, from sunrise to sunset, lasts about 9 h 26 min on an average December day.
The nearest other city in this atlas is Centennial (8 km away). In December its highs average 3.9°C, about as warm as Highlands Ranch, with 22 mm of rain.
Among the 498 cities listed in the United States, Highlands Ranch ranks 401st of 498 for the warmest December highs and joint 26th of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; Highlands Ranch is 6.7°C cooler than that mean.
From December to January, average highs rise by 0.4°C to 4.3°C, and monthly rainfall stays at 22 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
Highlands Ranch climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 4.3°C-10.5°C | -10.5°C | 22 | 5.3 | 9.710 h |
| February | 5.5°C-9.6°C | -9.6°C | 24 | 5.7 | 10.711 h |
| March | 10.1°C-5.6°C | -5.6°C | 51 | 7.8 | 11.912 h |
| April | 13.6°C-1.5°C | -1.5°C | 75 | 10.0 | 13.213 h |
| May | 19.2°C4.5°C | 4.5°C | 88 | 12.5 | 14.314 h |
| June | 25.7°C10.3°C | 10.3°C | 57 | 9.6 | 14.915 h |
| July | 28.8°C13.9°C | 13.9°C | 56 | 9.7 | 14.715 h |
| August | 27.6°C13.2°C | 13.2°C | 47 | 9.3 | 13.714 h |
| September | 23.8°C8.9°C | 8.9°C | 39 | 6.3 | 12.512 h |
| October | 16.5°C1.8°C | 1.8°C | 42 | 6.3 | 11.211 h |
| November | 9.1°C-5.5°C | -5.5°C | 31 | 5.9 | 10.010 h |
| December, selected | 3.8°C-10.6°C | -10.6°C | 22 | 4.9 | 9.49 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
- Centennial in DecemberUnited States · 8 kmHigh 3.9°C · Low -10.3°C · 22 mm rain
- Lakewood in DecemberUnited States · 19 kmHigh 4.4°C · Low -9.1°C · 21 mm rain
- Denver in DecemberUnited States · 21 kmHigh 4.4°C · Low -9.6°C · 21 mm rain
- Aurora (Colorado), United States in DecemberUnited States · 23 kmHigh 5.0°C · Low -8.0°C · 14 mm rain
- Arvada in DecemberUnited States · 29 kmHigh 4.4°C · Low -9.7°C · 21 mm rain
- Westminster (Colorado), United States in DecemberUnited States · 32 kmHigh 4.2°C · Low -9.8°C · 21 mm rain
- Thornton in DecemberUnited States · 35 kmHigh 4.0°C · Low -9.7°C · 21 mm rain
- Boulder in DecemberUnited States · 57 kmHigh 4.0°C · Low -8.8°C · 23 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 Highlands Ranch) is explained once on the Highlands Ranch year overview and on the Sources, method and limits page.
Centennial lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.