United States · 1991–2020

Best time to visit
Denver.

September leads for comfortable weather in Denver: typically 25.1°C by day, 13.7°C at night, with 126 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high25.1°C

Typical low13.7°C

Rain in September126 mm

Comfort

September

September · May · June

77climate match

Beach

July

July · August · June

73climate match

Outdoors

May

May · October · April

73climate match

The weakest month is January, scoring 5 against September’s 77 — days reach only 3.3°C, 21° below the 24°C the score treats as ideal.

Month by month

The whole year,
without the guesswork.

The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.

Jan

53.3° / -5.5°

Feb

55° / -4.6°

Mar

1810.7° / -0.3°

Apr

4617° / 4.9°

May

7422.6° / 10.8°

Jun

6927.4° / 16.1°

Jul

6029.7° / 18.6°

Aug

6728.7° / 17.6°

Sep

7725.1° / 13.7°

Oct

5318.3° / 7.2°

Nov

2912.2° / 1.7°

Dec

56.2° / -2.6°

Monthly climate evidence for Denver — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	3.3°C	-5.5°C	58 mm	7.2	9 h 36	5	Good coverage
February	5°C	-4.6°C	58 mm	7.5	10 h 36	5	Good coverage
March	10.7°C	-0.3°C	77 mm	7.9	11 h 49	18	Good coverage
April	17°C	4.9°C	88 mm	9.1	13 h 13	46	Good coverage
May	22.6°C	10.8°C	91 mm	9.8	14 h 23	74	Good coverage
June	27.4°C	16.1°C	120 mm	9.6	15 h 01	69	Good coverage
July	29.7°C	18.6°C	106 mm	8.6	14 h 46	60	Good coverage
August	28.7°C	17.6°C	93 mm	8.5	13 h 46	67	Good coverage
September	25.1°C	13.7°C	126 mm	7.6	12 h 24	77	Good coverage
October	18.3°C	7.2°C	102 mm	7.9	11 h 04	53	Good coverage
November	12.2°C	1.7°C	70 mm	6.2	9 h 53	29	Good coverage
December	6.2°C	-2.6°C	81 mm	8.3	9 h 19	5	Good coverage

Records at LANCASTER AP, 1999–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	20.6°C29 Jan 2002	-21.7°C21 Jan 2026	42 mm30 Jan 2013	132 mm2024 · driest 16 mm in 2025	27
February	27.8°C21 Feb 2018	-18.8°C24 Feb 2015	48 mm6 Feb 2004	138 mm2018 · driest 7 mm in 2002	27
March	28.3°C29 Mar 2025	-19.3°C7 Mar 2015	77 mm21 Mar 2000	156 mm2000 · driest 23 mm in 2006	28
April	32.2°C17 Apr 2002	-6.0°C6 Apr 2016	51 mm15 Apr 2007	162 mm2011 · driest 41 mm in 2015	28
May	35.0°C31 May 2022	-0.5°C9 May 2020	58 mm13 May 2002	218 mm2025 · driest 7 mm in 2023	28
June	36.7°C2 Jun 2023	6.1°C1 Jun 2009	144 mm25 Jun 2000	332 mm2006 · driest 16 mm in 2026	28
July	39.4°C22 Jul 2011	10.0°C3 Jul 2001	82 mm14 Jul 2010	230 mm2018 · driest 16 mm in 1999	28
August	37.8°C23 Aug 2012	7.8°C21 Aug 2000	83 mm18 Aug 2021	286 mm2018 · driest 30 mm in 2023	27
September	36.7°C7 Sep 2023	2.8°C29 Sep 2000	154 mm30 Sep 2010	332 mm2011 · driest 20 mm in 2005	27
October	35.0°C2 Oct 2019	-2.8°C29 Oct 2001	99 mm15 Oct 2014	206 mm2005 · driest 1 mm in 2024	27
November	27.8°C6 Nov 2024	-9.3°C19 Nov 2014	64 mm16 Nov 2006	209 mm2018 · driest 22 mm in 2001	27
December	22.8°C5 Dec 2001	-18.3°C7 Dec 2002	71 mm17 Dec 2000	159 mm2023 · driest 21 mm in 2021	27

Typical days per month at LANCASTER AP, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	0	0	26	2
February	0	0	24	2
March	<1	0	17	3
April	3	<1	4	3
May	11	3	<1	3
June	23	8	0	4
July	29	15	0	3
August	28	11	0	3
September	16	4	0	3
October	4	<1	2	3
November	<1	0	12	3
December	0	0	23	3

How often, not how much — every day in LANCASTER AP’s record sorted by what it was actually like, rather than averaged
Month	Warm & dry days	Wet days	Washouts	Week with 3+ wet days	Daytime mean has ranged
January	<1%	23%	6%	25%	0.1–6.8°C
February	1%	27%	6%	29%	1.0–8.9°C
March	8%	25%	8%	27%	7.7–14.0°C
April	25%	30%	9%	39%	15.5–19.5°C
May	52%	32%	10%	40%	20.7–24.8°C
June	68%	32%	11%	38%	26.1–28.8°C
July	72%	28%	11%	34%	27.8–31.8°C
August	72%	28%	9%	30%	26.9–30.1°C
September	70%	26%	11%	29%	23.3–27.1°C
October	33%	25%	10%	25%	16.7–21.1°C
November	8%	21%	8%	21%	9.6–14.3°C
December	<1%	27%	10%	27%	3.3–9.7°C

A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.

2000Each stripe is one year’s mean temperature against the 26-year average. Warmest: 2023. Coolest: 2014.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5186794
NOAA station: USW00054737 · LANCASTER AP
Station distance: 18.3 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 21 usable years
Daylight: Calculated from latitude 40.23°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Important limit: Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.

These places read the same station, so their numbers are identical — distance from LANCASTER AP is what differs

Ephrata→Lititz→East Petersburg→Akron→Rothsville→Brownstown→

Or put two places side by side: Denver vs Ephrata

Best time to visitDenver.

September

July

May

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
Denver.

The whole year,
without the guesswork.

Nearby, measured,
and named.