United States · 1991–2020

Best time to visit
Dayton.

September leads for comfortable weather in Dayton: typically 25.2°C by day, 11.8°C at night, with 88 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high25.2°C

Typical low11.8°C

Rain in September88 mm

Comfort

September

September · August · June

80climate match

Beach

July

July · August · June

71climate match

Outdoors

October

October · May · September

71climate match

The weakest month is January, scoring 5 against September’s 80 — 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

5-0.2° / -9.5°

Feb

51.7° / -8.2°

Mar

98.5° / -2.6°

Apr

4016.4° / 3.2°

May

6622.3° / 9.2°

Jun

7127° / 14.5°

Jul

6828.8° / 16.7°

Aug

7227.9° / 15.8°

Sep

8025.2° / 11.8°

Oct

5117.6° / 5.3°

Nov

169.9° / -0.8°

Dec

52.5° / -6.5°

Monthly climate evidence for Dayton — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	-0.2°C	-9.5°C	52 mm	6.9	9 h 29	5	Good coverage
February	1.7°C	-8.2°C	49 mm	6.5	10 h 33	5	Good coverage
March	8.5°C	-2.6°C	62 mm	7.5	11 h 48	9	Good coverage
April	16.4°C	3.2°C	94 mm	9.7	13 h 16	40	Good coverage
May	22.3°C	9.2°C	118 mm	10	14 h 29	66	Good coverage
June	27°C	14.5°C	123 mm	9.6	15 h 09	71	Good coverage
July	28.8°C	16.7°C	98 mm	7.8	14 h 53	68	Good coverage
August	27.9°C	15.8°C	104 mm	7.6	13 h 50	72	Good coverage
September	25.2°C	11.8°C	88 mm	6.7	12 h 25	80	Good coverage
October	17.6°C	5.3°C	82 mm	7.6	11 h 01	51	Good coverage
November	9.9°C	-0.8°C	68 mm	7.4	9 h 48	16	Good coverage
December	2.5°C	-6.5°C	53 mm	6.9	9 h 12	5	Good coverage

Records at MARSEILLES LOCK/DAM, 1949–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	18.3°C8 Jan 2008	-32.8°C5 Jan 1999	74 mm11 Jan 2020	126 mm2020 · driest 6 mm in 2022	32
February	22.8°C27 Feb 2024	-27.8°C11 Feb 2011	44 mm20 Feb 2018	150 mm2018 · driest 7 mm in 2026	31
March	28.3°C21 Mar 2012	-21.7°C1 Mar 2015	53 mm8 Mar 2009	171 mm2009 · driest 11 mm in 2015	31
April	32.2°C19 Apr 2002	-7.8°C9 Apr 1997	106 mm18 Apr 2013	191 mm2013 · driest 12 mm in 2023	30
May	35.6°C28 May 2018	-3.3°C3 May 2005	113 mm7 May 2012	233 mm2019 · driest 39 mm in 2026	31
June	36.7°C29 Jun 2012	3.3°C1 Jun 2003	88 mm14 Jun 2015	273 mm2015 · driest 30 mm in 2022	31
July	38.9°C25 Jul 2005	7.2°C28 Jul 1977	73 mm4 Jul 2001	204 mm2019 · driest 10 mm in 2012	31
August	36.7°C3 Aug 2006	7.2°C31 Aug 2009	152 mm24 Aug 2007	367 mm2007 · driest 19 mm in 2021	29
September	36.1°C2 Sep 2000	-0.6°C24 Sep 2012	141 mm28 Sep 2019	288 mm2019 · driest 9 mm in 2017	28
October	32.2°C4 Oct 2018	-5.6°C21 Oct 2018	73 mm14 Oct 2001	175 mm2009 · driest 12 mm in 2005	29
November	26.1°C2 Nov 2000	-17.8°C29 Nov 1976	47 mm30 Nov 2006	150 mm2015 · driest 1 mm in 2021	30
December	21.7°C4 Dec 2012	-26.7°C26 Dec 2000	42 mm5 Dec 1999	145 mm2015 · driest 5 mm in 2017	30

Typical days per month at MARSEILLES LOCK/DAM, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	29	2	5
February	0	0	25	2	5
March	<1	0	23	2	2
April	4	<1	9	3	<1
May	11	3	1	4	0
June	22	8	0	4	0
July	28	13	0	3	0
August	26	8	0	3	0
September	16	5	0	3	0
October	5	<1	6	3	<1
November	<1	0	18	2	<1
December	0	0	27	2	4

How often, not how much — every day in MARSEILLES LOCK/DAM’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%	21%	4%	19%	-4.0–3.2°C
February	<1%	21%	4%	19%	-4.0–5.8°C
March	6%	25%	7%	28%	5.9–13.4°C
April	22%	32%	11%	40%	14.0–19.3°C
May	48%	31%	11%	38%	20.1–25.4°C
June	67%	28%	12%	32%	25.5–29.2°C
July	75%	24%	10%	25%	27.3–30.9°C
August	75%	23%	9%	20%	26.1–29.2°C
September	71%	23%	9%	23%	23.4–27.1°C
October	30%	22%	8%	23%	16.1–20.1°C
November	6%	23%	7%	23%	6.5–13.6°C
December	0%	23%	5%	24%	-1.2–6.2°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.

1998Each stripe is one year’s mean temperature against the 25-year average. Warmest: 2024. Coolest: 2014.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4889530
NOAA station: USC00115372 · MARSEILLES LOCK/DAM
Station distance: 7.1 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 23 usable years
Daylight: Calculated from latitude 41.38°, 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 MARSEILLES LOCK/DAM is what differs

Marseilles→Sheridan→Seneca→Sulphur Springs→Blakes→Carriage Lane Estates→

Or put two places side by side: Dayton vs Marseilles

Best time to visitDayton.