United States · 1991–2020

Best time to visit
Diann.

September leads for comfortable weather in Diann: typically 24.5°C by day, 12°C at night, with 72 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high24.5°C

Typical low12°C

Rain in September72 mm

Comfort

September

September · June · August

84climate match

Beach

July

July · August · June

75climate match

Outdoors

May

May · September · October

73climate match

The weakest month is January, scoring 5 against September’s 84 — days reach only 0.2°C, 24° 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

50.2° / -8.1°

Feb

51.4° / -8°

Mar

57.4° / -3.1°

Apr

3715.1° / 2.6°

May

6421.3° / 9°

Jun

7826.7° / 14.8°

Jul

6929.1° / 16.8°

Aug

7427.8° / 15.9°

Sep

8424.5° / 12°

Oct

5017° / 5.4°

Nov

189.8° / 0.2°

Dec

53.1° / -4.3°

Monthly climate evidence for Diann — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 23 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	0.2°C	-8.1°C	62 mm	9.1	1.2°C	9 h 26	5	Good coverage
February	1.4°C	-8°C	54 mm	7.7	0.8°C	10 h 31	5	Good coverage
March	7.4°C	-3.1°C	66 mm	8.2	2.0°C	11 h 48	5	Good coverage
April	15.1°C	2.6°C	78 mm	9.1	6.5°C	13 h 17	37	Good coverage
May	21.3°C	9°C	103 mm	10.7	13.2°C	14 h 32	64	Good coverage
June	26.7°C	14.8°C	90 mm	8.5	19.6°C	15 h 13	78	Good coverage
July	29.1°C	16.8°C	77 mm	8.4	23.8°C	14 h 57	69	Good coverage
August	27.8°C	15.9°C	85 mm	7.8	24.1°C	13 h 52	74	Good coverage
September	24.5°C	12°C	72 mm	7.5	21.1°C	12 h 26	84	Good coverage
October	17°C	5.4°C	66 mm	8.7	14.5°C	11 h	50	Good coverage
November	9.8°C	0.2°C	69 mm	7.6	7.9°C	9 h 45	18	Good coverage
December	3.1°C	-4.3°C	66 mm	8.4	3.2°C	9 h 08	5	Good coverage

Records at DUNDEE, 2001–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	18.3°C8 Jan 2008	-26.1°C16 Jan 2009	52 mm12 Jan 2020	141 mm2024 · driest 14 mm in 2022	25
February	22.8°C28 Feb 2024	-26.1°C20 Feb 2015	41 mm28 Feb 2023	118 mm2023 · driest 4 mm in 2026	25
March	29.4°C23 Mar 2012	-20.6°C2 Mar 2003	48 mm11 Mar 2009	118 mm2017 · driest 17 mm in 2013	26
April	30.6°C25 Apr 2009	-7.2°C9 Apr 2018	41 mm3 Apr 2025	152 mm2026 · driest 28 mm in 2012	26
May	35.0°C29 May 2012	-2.8°C9 May 2020	55 mm11 May 2002	192 mm2004 · driest 26 mm in 2023	25
June	37.8°C29 Jun 2012	4.4°C1 Jun 2003	82 mm21 Jun 2021	217 mm2015 · driest 16 mm in 2022	26
July	38.3°C5 Jul 2012	7.2°C1 Jul 2001	73 mm3 Jul 2008	132 mm2005 · driest 20 mm in 2018	26
August	36.7°C8 Aug 2001	7.8°C27 Aug 2025	95 mm24 Aug 2023	229 mm2007 · driest 22 mm in 2010	25
September	36.1°C3 Sep 2011	2.2°C19 Sep 2020	58 mm24 Sep 2025	137 mm2021 · driest 10 mm in 2022	25
October	32.2°C8 Oct 2007	-3.9°C30 Oct 2008	42 mm14 Oct 2003	168 mm2021 · driest 4 mm in 2005	25
November	26.7°C10 Nov 2020	-13.3°C13 Nov 2019	51 mm23 Nov 2011	187 mm2011 · driest 18 mm in 2009	25
December	20.0°C5 Dec 2001	-21.7°C25 Dec 2004	49 mm1 Dec 2006	117 mm2008 · driest 22 mm in 2017	24

Typical days per month at DUNDEE, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	27	2	8
February	0	0	25	2	7
March	<1	0	22	2	4
April	3	<1	8	3	<1
May	8	2	<1	3	0
June	21	7	0	3	0
July	28	13	0	3	0
August	26	9	0	3	0
September	14	4	0	3	0
October	3	<1	4	2	0
November	<1	0	14	2	1
December	0	0	24	2	5

How often, not how much — every day in DUNDEE’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%	29%	6%	33%	-3.3–3.4°C
February	0%	26%	6%	28%	-1.7–5.8°C
March	4%	27%	7%	31%	4.6–11.7°C
April	17%	32%	10%	43%	12.9–17.6°C
May	41%	34%	10%	43%	19.4–23.8°C
June	71%	28%	10%	31%	25.4–28.0°C
July	72%	28%	8%	30%	27.2–30.9°C
August	74%	25%	10%	23%	26.6–29.4°C
September	67%	24%	8%	29%	22.7–26.1°C
October	26%	28%	7%	30%	15.5–19.4°C
November	5%	26%	7%	29%	6.3–13.2°C
December	<1%	27%	7%	30%	0.8–6.7°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.

2002Each stripe is one year’s mean temperature against the 23-year average. Warmest: 2024. Coolest: 2014.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4990822
NOAA station: USC00202308 · DUNDEE
Station distance: 2.8 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 19 usable years
Daylight: Calculated from latitude 41.93°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 23 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 DUNDEE is what differs

Temperance→Dundee→Petersburg→Erie→Grape→Hillcrest Orchard→

Or put two places side by side: Diann vs Temperance

Best time to visitDiann.

September

July

May

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
Diann.

The whole year,
without the guesswork.

Nearby, measured,
and named.