United States · 1991–2020

Best time to visit
Byron.

September leads for comfortable weather in Byron: typically 26.9°C by day, 13°C at night, with 78 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high26.9°C

Typical low13°C

Rain in September78 mm

Comfort

September

September · May · June

79climate match

Beach

August

August · June · July

71climate match

Outdoors

October

October · April · May

85climate match

The weakest month is January, scoring 5 against September’s 79 — days reach only 3.3°C, 21° below the 24°C the score treats as ideal, and nights drop to -8.6°C.

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° / -8.6°

Feb

56° / -6.7°

Mar

3212.7° / -1.3°

Apr

5318.3° / 4.4°

May

7623.8° / 10.8°

Jun

6329.9° / 16.8°

Jul

5032.4° / 19.4°

Aug

5831.2° / 18.3°

Sep

7926.9° / 13°

Oct

6319.6° / 5.9°

Nov

2911.5° / -1.5°

Dec

54.9° / -6.5°

Monthly climate evidence for Byron — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	3.3°C	-8.6°C	15 mm	2.6	9 h 37	5	Strong coverage
February	6°C	-6.7°C	24 mm	3	10 h 37	5	Strong coverage
March	12.7°C	-1.3°C	35 mm	4.6	11 h 49	32	Strong coverage
April	18.3°C	4.4°C	74 mm	7.1	13 h 12	53	Strong coverage
May	23.8°C	10.8°C	111 mm	8.5	14 h 22	76	Strong coverage
June	29.9°C	16.8°C	108 mm	7.2	15 h	63	Strong coverage
July	32.4°C	19.4°C	110 mm	7.3	14 h 45	50	Strong coverage
August	31.2°C	18.3°C	95 mm	6.7	13 h 45	58	Strong coverage
September	26.9°C	13°C	78 mm	5.5	12 h 24	79	Strong coverage
October	19.6°C	5.9°C	64 mm	4.8	11 h 04	63	Strong coverage
November	11.5°C	-1.5°C	30 mm	3.6	9 h 55	29	Strong coverage
December	4.9°C	-6.5°C	25 mm	2.6	9 h 20	5	Strong coverage

What has changed

Byron runs +0.7°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

-0.5

Mar

+2.0

Apr

-0.1

May

0.0

Jun

+1.5

Jul

-0.3

Aug

-0.3

Sep

+2.3

Oct

+0.4

Nov

+1.4

Dec

+1.9

September daytime highs, 2011–2025. Last recorded: 28.3°C.

Records at BELLEVILLE, 1935–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	25.6°C10 Jan 1990	-28.3°C12 Jan 1974	26 mm30 Jan 2001	49 mm1960 · driest 0 mm in 1986	89
February	29.4°C29 Feb 1972	-29.4°C16 Feb 2021	56 mm27 Feb 1948	86 mm1948 · driest 0 mm in 2020	89
March	36.1°C22 Mar 2026	-25.6°C11 Mar 1948	78 mm30 Mar 1976	246 mm1987 · driest 1 mm in 1956	88
April	36.1°C24 Apr 1989	-12.2°C3 Apr 1936	75 mm14 Apr 1987	192 mm1984 · driest 1 mm in 1989	90
May	37.8°C12 May 1956	-3.9°C2 May 1967	122 mm24 May 2007	276 mm1938 · driest 4 mm in 1966	90
June	43.9°C19 Jun 1936	4.4°C1 Jun 2012	165 mm23 Jun 2003	299 mm1943 · driest 14 mm in 1950	91
July	45.0°C17 Jul 1936	7.8°C5 Jul 1972	132 mm26 Jul 1945	452 mm1993 · driest 6 mm in 1936	92
August	45.6°C13 Aug 1936	5.0°C20 Aug 1950	109 mm19 Aug 2003	274 mm1977 · driest 6 mm in 1955	89
September	45.0°C3 Sep 1947	-3.9°C29 Sep 1984	179 mm5 Sep 1958	297 mm1958 · driest 0 mm in 1956	90
October	38.3°C5 Oct 1947	-10.0°C31 Oct 1993	117 mm12 Oct 2005	219 mm2008 · driest 0 mm in 1952	90
November	29.4°C8 Nov 1980	-23.3°C28 Nov 1952	56 mm17 Nov 1996	123 mm1996 · driest 0 mm in 1954	89
December	26.7°C23 Dec 1964	-31.7°C23 Dec 1989	57 mm16 Dec 1984	87 mm1984 · driest 0 mm in 1976	89

Typical days per month at BELLEVILLE, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	30	<1	2
February	<1	0	25	<1	2
March	2	<1	19	1	1
April	6	1	6	2	<1
May	14	5	<1	3	0
June	26	16	0	3	0
July	29	23	0	3	0
August	29	20	0	3	0
September	20	9	<1	2	0
October	7	1	5	2	<1
November	<1	0	18	<1	<1
December	0	0	29	<1	2

How often, not how much — every day in BELLEVILLE’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%	9%	2%	4%	-0.9–7.4°C
February	4%	11%	2%	8%	0.5–10.5°C
March	18%	17%	5%	13%	7.6–16.1°C
April	39%	23%	8%	24%	15.8–21.4°C
May	60%	28%	12%	34%	21.5–26.6°C
June	72%	27%	12%	29%	27.4–32.3°C
July	77%	23%	10%	21%	30.1–35.7°C
August	78%	22%	9%	20%	29.2–35.1°C
September	75%	19%	8%	17%	24.3–30.2°C
October	52%	15%	5%	12%	17.3–23.3°C
November	12%	11%	3%	6%	8.5–14.5°C
December	<1%	9%	2%	4%	1.6–8.4°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.

1936Each stripe is one year’s mean temperature against the 83-year average. Warmest: 1938. Coolest: 1993.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5065026
NOAA station: USC00140682 · BELLEVILLE
Station distance: 22.4 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 28 usable years
Daylight: Calculated from latitude 40.00°, 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 BELLEVILLE is what differs

Belleville→Cuba→Munden→Agenda→Brantford→Harbine→

Or put two places side by side: Byron vs Belleville

Best time to visitByron.