As of 12:42 MDT

Thornton, CO weather in December

96°

Thornton, Sunday, 9 August, 12:42

Overcast. Feels like 92°. High 96°, low 68°.

Pressure29.71 inHg

Wind9 mph N

Humidity17%

Visibility6.2 mi

Dew point44°

See detailed hourly forecast

In December, Thornton, CO averages a high of 40.2° and a low of 17.3°. About 0.9 inches of precipitation fall over the month (5 wet days). The record high is 72.3° (2025) and the record low -26° (1990). Normals are computed over the last 60 years.

Day	High	Low	Chance of precip.	Record high	Record low
1	43°	19.8°	10%	71.1° (2021)	-3.6° (1985)
2	44.1°	20.3°	13%	66.2° (2021)	-3.5° (1985)
3	42.6°	19.9°	17%	64.9° (2017)	-6° (1978)
4	44.1°	19.4°	8%	64° (2007)	-2.2° (2005)
5	42.8°	18.5°	13%	66.4° (2012)	-16.8° (1972)
6	39.7°	18.5°	17%	58.3° (2023)	-23.8° (1972)
7	40.8°	19.2°	22%	60.1° (1965)	-8.5° (1972)
8	40.6°	18.7°	22%	60.3° (1981)	-19.1° (1978)
9	41°	17.2°	17%	61.2° (1981)	-16.2° (1978)
10	42.1°	17.1°	12%	62.1° (1990)	-20.6° (1972)
11	42.1°	18.3°	15%	64.6° (2025)	-13.4° (1972)
12	41.7°	18.3°	12%	65.1° (2017)	-18.9° (1961)
13	41.5°	18.5°	17%	62.8° (2025)	-11.6° (1961)
14	41°	18.5°	18%	62.8° (2021)	-7.2° (1972)
15	40.8°	17.8°	17%	60.8° (2025)	-11.6° (1972)
16	40.5°	17.2°	12%	64.4° (2025)	-4.2° (1960)
17	40.8°	18.5°	12%	67.5° (1980)	-4.9° (2016)
18	39.7°	17.6°	20%	57° (2013)	-15° (2016)
19	40.6°	17.6°	20%	68.5° (2025)	-6.7° (2016)
20	40.5°	17.4°	13%	60.3° (1981)	-7.2° (1973)
21	39.7°	16.9°	18%	60.1° (2025)	-18.2° (1990)
22	38.1°	15.8°	23%	72.3° (2025)	-26° (1990)
23	37.6°	15.4°	18%	65.5° (1964)	-17.9° (2022)
24	37.2°	14.2°	22%	66.2° (2025)	-20.9° (1983)
25	38.8°	15.6°	18%	69.3° (2025)	-15.5° (1983)
26	39.2°	16°	12%	63.5° (2025)	-12.5° (1962)
27	38.8°	16.3°	17%	66.9° (1980)	-9.9° (2015)
28	38.1°	15.6°	22%	57.6° (1999)	-8.1° (2015)
29	37°	14.4°	10%	58.3° (2017)	-14.1° (1983)
30	37.4°	14.2°	17%	61.9° (1980)	-8.9° (2015)
31	35.2°	13.1°	18%	58.1° (2005)	-17.3° (2014)