United States · 1991–2020

Best time to visit
Durham.

September leads for comfortable weather in Durham: typically 24.6°C by day, 12.3°C at night, with 107 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high24.6°C

Typical low12.3°C

Rain in September107 mm

Comfort

September

September · June · August

79climate match

Beach

July

July · August · June

74climate match

Outdoors

May

May · October · September

76climate match

The weakest month is January, scoring 5 against September’s 79 — days reach only 2.8°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

52.8° / -7.4°

Feb

54.3° / -6.4°

Mar

89° / -2°

Apr

3715.7° / 3.4°

May

6721.6° / 9°

Jun

7426° / 14°

Jul

6729.2° / 17.3°

Aug

7128.3° / 16.5°

Sep

7924.6° / 12.3°

Oct

4717.8° / 5.7°

Nov

2211.7° / 0.3°

Dec

55.6° / -4.1°

Monthly climate evidence for Durham — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 40 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	2.8°C	-7.4°C	67 mm	7.3	4.2°C	9 h 29	5	Good coverage
February	4.3°C	-6.4°C	73 mm	6.9	2.4°C	10 h 32	5	Good coverage
March	9°C	-2°C	90 mm	7.6	3.2°C	11 h 48	8	Good coverage
April	15.7°C	3.4°C	103 mm	8.3	6.7°C	13 h 16	37	Good coverage
May	21.6°C	9°C	92 mm	9.7	11.7°C	14 h 29	67	Good coverage
June	26°C	14°C	118 mm	9.2	17.0°C	15 h 10	74	Good coverage
July	29.2°C	17.3°C	89 mm	8	21.2°C	14 h 54	67	Good coverage
August	28.3°C	16.5°C	89 mm	8.2	22.3°C	13 h 50	71	Good coverage
September	24.6°C	12.3°C	107 mm	6.9	21.1°C	12 h 25	79	Good coverage
October	17.8°C	5.7°C	114 mm	8	17.7°C	11 h 01	47	Good coverage
November	11.7°C	0.3°C	87 mm	7.4	12.8°C	9 h 47	22	Good coverage
December	5.6°C	-4.1°C	107 mm	8.9	8.1°C	9 h 11	5	Good coverage

Records at MERIDEN MARKHAM MUNI AP, 1999–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	21.7°C6 Jan 2007	-25.5°C7 Jan 2018	83 mm24 Jan 2019	164 mm2023 · driest 21 mm in 2026	27
February	21.1°C21 Feb 2018	-23.2°C24 Feb 2015	88 mm13 Feb 2008	257 mm2008 · driest 12 mm in 2015	27
March	26.1°C22 Mar 2012	-18.3°C7 Mar 2003	75 mm23 Mar 2024	246 mm2010 · driest 13 mm in 2012	27
April	35.0°C17 Apr 2002	-6.0°C3 Apr 2021	80 mm13 Apr 2020	219 mm2007 · driest 20 mm in 2013	26
May	35.6°C26 May 2010	-2.2°C7 May 2001	82 mm12 May 2006	199 mm2025 · driest 31 mm in 2015	26
June	38.3°C24 Jun 2025	2.2°C1 Jun 2001	75 mm7 Jun 2013	269 mm2006 · driest 24 mm in 2021	27
July	38.9°C22 Jul 2011	7.2°C3 Jul 2001	85 mm9 Jul 2021	213 mm2021 · driest 12 mm in 2019	27
August	38.9°C9 Aug 2001	7.8°C31 Aug 2025	80 mm18 Aug 2024	307 mm2011 · driest 13 mm in 2005	27
September	36.1°C8 Sep 2015	0.6°C22 Sep 2020	115 mm16 Sep 1999	256 mm2003 · driest 20 mm in 2014	27
October	30.6°C2 Oct 2019	-6.0°C31 Oct 2020	109 mm8 Oct 2005	418 mm2005 · driest 10 mm in 2024	27
November	27.8°C1 Nov 2024	-12.8°C28 Nov 2002	67 mm27 Nov 2013	179 mm2018 · driest 14 mm in 2012	27
December	22.2°C6 Dec 2001	-19.3°C31 Dec 2017	73 mm12 Dec 2010	219 mm2023 · driest 40 mm in 2021	27

Typical days per month at MERIDEN MARKHAM MUNI AP, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	0	0	28	2
February	0	0	25	2
March	0	0	21	3
April	2	<1	8	3
May	9	3	<1	3
June	19	6	0	4
July	28	14	0	3
August	27	10	0	3
September	15	3	0	3
October	3	<1	5	3
November	<1	0	16	3
December	0	0	26	3

How often, not how much — every day in MERIDEN MARKHAM MUNI 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	0%	23%	7%	22%	0.2–6.1°C
February	<1%	25%	8%	30%	0.9–7.5°C
March	4%	26%	9%	31%	5.9–12.6°C
April	20%	29%	10%	34%	13.7–17.7°C
May	50%	32%	10%	39%	20.1–23.6°C
June	68%	30%	12%	39%	25.2–28.0°C
July	73%	27%	11%	30%	27.2–31.0°C
August	74%	26%	10%	27%	27.0–30.1°C
September	71%	24%	12%	27%	23.3–26.1°C
October	30%	25%	11%	24%	16.2–20.3°C
November	5%	25%	9%	26%	9.6–14.3°C
December	<1%	29%	12%	35%	2.9–8.7°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 25-year average. Warmest: 2024. Coolest: 2003.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4833123
NOAA station: USW00054788 · MERIDEN MARKHAM MUNI AP
Station distance: 12.6 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 20 usable years
Daylight: Calculated from latitude 41.48°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 40 km from the place centre. A sheltered bay can run warmer than the open sea it is measured from.
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 MERIDEN MARKHAM MUNI AP is what differs

Waterbury→Meriden→Middletown→Southington→Cheshire→Wallingford Center→

Or put two places side by side: Durham vs Waterbury

Best time to visitDurham.

September

July

May

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
Durham.

The whole year,
without the guesswork.

Nearby, measured,
and named.