United States · 1991–2020

Best time to visit
Cornwell.

December leads for comfortable weather in Cornwell: typically 24.8°C by day, 10.7°C at night, with 51 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortDecember

Typical high24.8°C

Typical low10.7°C

Rain in December51 mm

Comfort

December

December · November · January

86climate match

Beach

October

October · November · April

72climate match

Outdoors

January

January · December · February

81climate match

The weakest month is August, scoring 20 against December’s 86 — days average 33.9°C, 10° above the 24°C the score treats as ideal, and 216 mm of rain falls.

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

8323.7° / 8.5°

Feb

8125.6° / 9.8°

Mar

7527.5° / 11.1°

Apr

7230° / 13.6°

May

5632.2° / 16.5°

Jun

2333.3° / 20.1°

Jul

2233.9° / 20.8°

Aug

2033.9° / 21.3°

Sep

3132.8° / 20.9°

Oct

6330.5° / 17.6°

Nov

8527.1° / 13.4°

Dec

8624.8° / 10.7°

Monthly climate evidence for Cornwell — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	23.7°C	8.5°C	55 mm	4.7	10 h 35	83	Strong coverage
February	25.6°C	9.8°C	57 mm	4.5	11 h 11	81	Strong coverage
March	27.5°C	11.1°C	73 mm	4.7	11 h 55	75	Strong coverage
April	30°C	13.6°C	64 mm	4.9	12 h 47	72	Strong coverage
May	32.2°C	16.5°C	111 mm	7	13 h 29	56	Strong coverage
June	33.3°C	20.1°C	225 mm	14.3	13 h 51	23	Strong coverage
July	33.9°C	20.8°C	212 mm	14	13 h 43	22	Strong coverage
August	33.9°C	21.3°C	216 mm	14.5	13 h 07	20	Strong coverage
September	32.8°C	20.9°C	182 mm	12.9	12 h 17	31	Strong coverage
October	30.5°C	17.6°C	87 mm	7.3	11 h 28	63	Strong coverage
November	27.1°C	13.4°C	44 mm	3.6	10 h 46	85	Strong coverage
December	24.8°C	10.7°C	51 mm	4.7	10 h 25	86	Strong coverage

What has changed

Cornwell runs +0.8°C
on the 1961–1990 baseline.

Each bar compares the 2011–2025 daytime average for that month against the same month in 1961–1990, measured at the same station. Months where the older record is too thin to compare are left blank.

Jan

+0.6

Feb

+2.7

Mar

+1.4

Apr

+1.1

May

+0.5

Jun

+0.1

Jul

+0.3

Aug

+0.5

Sep

+0.3

Oct

+0.3

Nov

+0.3

Dec

+1.7

December daytime highs, 2011–2025. Last recorded: 26.2°C.

Records at ARCHBOLD BIO STN, 1969–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	31.7°C20 Jan 2001	-10.6°C12 Jan 1982	101 mm16 Jan 1991	245 mm2016 · driest 2 mm in 1976	58
February	33.3°C28 Feb 2001	-7.8°C14 Feb 2006	109 mm3 Feb 1998	276 mm1983 · driest 0 mm in 2001	58
March	35.0°C27 Mar 2023	-6.7°C2 Mar 1986	119 mm13 Mar 1984	259 mm2010 · driest 1 mm in 2020	58
April	36.7°C25 Apr 1999	-2.8°C4 Apr 1987	112 mm1 Apr 1972	242 mm2021 · driest 1 mm in 2006	58
May	37.8°C30 May 1973	2.2°C8 May 1992	71 mm14 May 2011	367 mm2018 · driest 19 mm in 2024	58
June	38.9°C5 Jun 1985	10.0°C1 Jun 1971	124 mm9 Jun 2002	474 mm2002 · driest 23 mm in 1998	58
July	39.4°C3 Jul 1998	14.4°C7 Jul 1983	101 mm6 Jul 1986	439 mm2001 · driest 93 mm in 1994	58
August	38.3°C20 Aug 1969	15.6°C19 Aug 2000	152 mm31 Aug 2006	509 mm2006 · driest 49 mm in 2000	57
September	37.2°C3 Sep 2000	12.8°C29 Sep 2006	151 mm11 Sep 2017	416 mm2022 · driest 18 mm in 1996	57
October	36.1°C11 Oct 2009	1.1°C25 Oct 2006	154 mm24 Oct 2005	235 mm2005 · driest 0 mm in 2010	57
November	35.6°C5 Nov 1972	-2.8°C27 Nov 2008	103 mm5 Nov 1998	151 mm1987 · driest 0 mm in 2008	57
December	32.8°C19 Dec 2016	-8.9°C28 Dec 2010	62 mm17 Dec 2003	193 mm1997 · driest 6 mm in 1981	57

Typical days per month at ARCHBOLD BIO STN, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	15	<1	3	2
February	18	5	2	2
March	25	10	1	2
April	28	18	<1	2
May	31	27	0	4
June	30	28	0	6
July	31	30	0	6
August	31	30	0	6
September	30	28	0	5
October	30	21	0	2
November	24	6	<1	1
December	18	2	2	2

How often, not how much — every day in ARCHBOLD BIO STN’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	67%	15%	5%	11%	21.2–26.2°C
February	73%	16%	6%	11%	22.3–28.2°C
March	80%	17%	7%	13%	25.2–29.7°C
April	84%	15%	7%	13%	28.1–31.3°C
May	78%	23%	11%	29%	30.9–33.3°C
June	55%	45%	20%	65%	32.1–34.4°C
July	55%	45%	21%	65%	32.9–34.8°C
August	55%	45%	20%	67%	33.2–34.7°C
September	57%	43%	18%	59%	32.0–33.6°C
October	79%	21%	7%	23%	29.2–31.6°C
November	83%	13%	5%	8%	25.6–28.6°C
December	73%	14%	5%	11%	22.6–26.6°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.

1969Each stripe is one year’s mean temperature against the 57-year average. Warmest: 2015. Coolest: 2010.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4151988
NOAA station: USC00080236 · ARCHBOLD BIO STN
Station distance: 33.3 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 30 usable years
Daylight: Calculated from latitude 27.38°, 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 ARCHBOLD BIO STN is what differs

Placid Lakes→Lake Placid→Archbold→Bairs Den→Bear Hollow→Childs→

Or put two places side by side: Cornwell vs Placid Lakes

Best time to visitCornwell.

December

October

January

The whole year,without the guesswork.

Cornwell runs +0.8°Con the 1961–1990 baseline.

Nearby, measured,and named.

Best time to visit
Cornwell.

The whole year,
without the guesswork.

Cornwell runs +0.8°C
on the 1961–1990 baseline.

Nearby, measured,
and named.