United States · 1991–2020

Best time to visit
Diagonal.

September leads for comfortable weather in Diagonal: typically 24.6°C by day, 11.7°C at night, with 94 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high24.6°C

Typical low11.7°C

Rain in September94 mm

Comfort

September

September · June · August

81climate match

Beach

July

July · August · June

73climate match

Outdoors

October

October · May · September

74climate match

The weakest month is January, scoring 5 against September’s 81 — days reach only -0.4°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

5-0.4° / -11.4°

Feb

52.8° / -8.6°

Mar

169.7° / -2.5°

Apr

4116.3° / 3.4°

May

6121.4° / 9.7°

Jun

7226.7° / 15.5°

Jul

6429.1° / 17.8°

Aug

6928.3° / 16.6°

Sep

8124.6° / 11.7°

Oct

5317.7° / 4.6°

Nov

189.4° / -2°

Dec

52.8° / -7.7°

Monthly climate evidence for Diagonal — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	-0.4°C	-11.4°C	20 mm	3.4	9 h 33	5	Strong coverage
February	2.8°C	-8.6°C	30 mm	4	10 h 35	5	Strong coverage
March	9.7°C	-2.5°C	54 mm	5.6	11 h 49	16	Strong coverage
April	16.3°C	3.4°C	93 mm	7.8	13 h 14	41	Strong coverage
May	21.4°C	9.7°C	138 mm	9.9	14 h 26	61	Strong coverage
June	26.7°C	15.5°C	129 mm	8.5	15 h 05	72	Strong coverage
July	29.1°C	17.8°C	109 mm	7.8	14 h 50	64	Strong coverage
August	28.3°C	16.6°C	109 mm	7.1	13 h 48	69	Strong coverage
September	24.6°C	11.7°C	94 mm	6	12 h 25	81	Strong coverage
October	17.7°C	4.6°C	71 mm	6.1	11 h 03	53	Strong coverage
November	9.4°C	-2°C	51 mm	4.5	9 h 51	18	Strong coverage
December	2.8°C	-7.7°C	45 mm	4	9 h 16	5	Strong coverage

What has changed

Diagonal runs +0.1°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

+0.4

Feb

-0.3

Mar

+1.1

Apr

-1.5

May

-0.8

Jun

+0.5

Jul

-0.4

Aug

-0.4

Sep

+1.3

Oct

-0.7

Nov

+0.1

Dec

+1.5

September daytime highs, 2011–2025. Last recorded: 27.7°C.

Records at MT AYR, 1893–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	19.4°C31 Jan 1989	-34.4°C12 Jan 1912	46 mm20 Jan 1904	74 mm1929 · driest 0 mm in 1984	127
February	26.7°C24 Feb 1930	-33.9°C3 Feb 1996	38 mm17 Feb 1911	108 mm1911 · driest 0 mm in 1948	127
March	33.3°C22 Mar 2026	-28.9°C5 Mar 1960	88 mm19 Mar 1982	186 mm1973 · driest 0 mm in 1936	131
April	33.3°C29 Apr 1910	-15.0°C5 Apr 1920	116 mm24 Apr 1897	230 mm1927 · driest 5 mm in 1948	131
May	39.4°C30 May 1934	-5.6°C3 May 1903	104 mm15 May 1943	300 mm1896 · driest 5 mm in 1947	130
June	40.6°C6 Jun 1933	2.2°C3 Jun 1969	142 mm5 Jun 2010	346 mm2010 · driest 1 mm in 1988	128
July	44.4°C25 Jul 1936	5.0°C29 Jul 1982	140 mm20 Jul 1990	443 mm1993 · driest 0 mm in 1947	128
August	43.9°C9 Aug 1934	2.8°C10 Aug 1917	131 mm1 Aug 1932	373 mm1932 · driest 0 mm in 1947	126
September	40.6°C5 Sep 1913	-4.4°C29 Sep 1899	161 mm19 Sep 2010	372 mm1926 · driest 8 mm in 1956	128
October	33.9°C4 Oct 1938	-17.8°C30 Oct 1925	102 mm31 Oct 1974	213 mm1941 · driest 0 mm in 1952	129
November	27.8°C1 Nov 1938	-26.1°C30 Nov 1964	158 mm17 Nov 1952	198 mm1934 · driest 0 mm in 1989	129
December	21.1°C16 Dec 2021	-33.3°C24 Dec 1989	86 mm15 Dec 2007	189 mm2007 · driest 0 mm in 2002	127

Typical days per month at MT AYR, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	29	<1	3
February	0	0	25	1	3
March	<1	0	21	2	1
April	3	<1	8	3	<1
May	9	1	<1	5	0
June	20	7	0	4	0
July	26	13	0	3	0
August	25	10	0	3	0
September	15	5	<1	3	0
October	4	<1	7	2	<1
November	<1	0	19	2	<1
December	0	0	27	2	2

How often, not how much — every day in MT AYR’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%	12%	2%	6%	-4.1–4.5°C
February	<1%	14%	3%	8%	-2.2–6.9°C
March	10%	18%	6%	17%	5.1–13.3°C
April	28%	25%	9%	28%	13.9–19.6°C
May	52%	29%	13%	34%	20.2–25.5°C
June	70%	28%	14%	32%	25.1–29.5°C
July	78%	22%	10%	21%	28.2–32.7°C
August	76%	24%	11%	24%	27.1–32.0°C
September	68%	22%	10%	21%	22.4–27.8°C
October	41%	18%	7%	17%	15.8–21.5°C
November	7%	15%	5%	10%	6.6–13.1°C
December	<1%	13%	3%	9%	-1.6–6.1°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.

1896Each stripe is one year’s mean temperature against the 110-year average. Warmest: 1931. Coolest: 1996.2023

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4853916
NOAA station: USC00135769 · MT AYR
Station distance: 14.3 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 28 usable years
Daylight: Calculated from latitude 40.81°, 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 MT AYR is what differs

Mount Ayr→Clearfield→Benton→Maloy→Delphos→Caledonia (historical)→

Or put two places side by side: Diagonal vs Mount Ayr

Best time to visitDiagonal.