Is this weather normal in Jefferson County?

Colorado · county records since 1895, through September 2026.

Weather › Colorado › Jefferson County

Jefferson County just had its warmest September ever recorded, +5° against the usual. Jefferson County is in extreme drought: NOAA's Palmer reading for September was -7.7.

This week

Usual for Oct 28 to Nov 3: highs near 55°, lows near 29°

That is the 1991 to 2020 average for these dates in Jefferson County. The Weather Service forecast fills in below.

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usual high for the datewarmercooler

The last 12 months

September 2026 ran +5° warmer than usual: the warmest September of 132 on record.
Top-10 warm months this past year: November 2025 (3rd warmest), December 2025 (warmest on record), February 2026 (2nd warmest), March 2026 (warmest on record), July 2026 (warmest on record), August 2026 (warmest on record).
11 of the last 12 months were warmer than usual.

Each bar is a month's average temperature against the usual for that month (1991 to 2020). Ranks compare the same month in every year since 1895.

Every year since 1895

18952025

Warming about 0.4° per decade since 1970.
Warmest year: 1934 (49.0°). Coldest: 1895 (42.6°).
4 of the 10 warmest years came in the last 10.

Rain and drought

12.3 inches in the last 12 months, against a usual 18.6 (66%).
September brought 1.13 in (usual 1.52): the 65th wettest of 132.
Drought reading for September: extreme drought (-7.7).

Rain and melted snow against the usual for each month. The drought reading is NOAA's Palmer index for the county.

Month by month in Jefferson County

Month	Usual high / low	Usual rain	Warmest	Coldest
January	43° / 18°	0.7 in	36.7° 1953	15.0° 1930
February	44° / 18°	0.8 in	40.2° 1954	17.1° 1899
March	51° / 24°	1.7 in	47.9° 2026	23.9° 1965
April	56° / 30°	2.4 in	49.5° 1946	34.4° 1920
May	65° / 38°	2.5 in	58.2° 1934	44.8° 1917
June	77° / 47°	1.8 in	67.0° 2012	55.2° 1951
July	82° / 53°	2.2 in	71.6° 2026	61.4° 1895
August	80° / 51°	2.2 in	69.4° 2026	60.3° 1927
September	73° / 44°	1.5 in	63.2° 2026	50.4° 1965
October	61° / 33°	1.2 in	54.8° 1950	37.6° 1969
November	50° / 24°	0.9 in	44.6° 1949	27.3° 1929
December	42° / 17°	0.7 in	39.7° 2025	18.8° 1983

Warmest and coldest are the month's whole-month average temperature, with the year it happened.