Mt. Vernon climate — normals and trends

Q: What is the climate of Mt. Vernon?

Mt. Vernon has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 13.8 °C and it receives 1,060 mm of precipitation per year.

Q: What is the hottest day ever recorded in Mt. Vernon?

The hottest day measured in Mt. Vernon between 1940 and 2025 was 14 July 1954, reaching 41.3 °C.

Q: What is the coldest day in Mt. Vernon?

The coldest day measured in Mt. Vernon between 1940 and 2025 was 2 February 1951, at -28.2 °C.

Q: Does it snow in Mt. Vernon?

Yes. Mt. Vernon gets on average 33.2 cm of snow per year and has around 77 frost days.

Q: Has the climate of Mt. Vernon warmed?

Yes: Mt. Vernon warmed by +1.4 °C between 1940 and 2025, a statistically significant trend.

Q: What is the wettest day in Mt. Vernon?

The wettest day measured in Mt. Vernon between 1940 and 2025 was 8 May 1961, with 123 mm of rain in 24 hours.

Q: What was the windiest day in Mt. Vernon?

The windiest day measured in Mt. Vernon between 1940 and 2025 was 5 April 1947, with winds reaching 47.7 km/h.

Q: What is the warmest month in Mt. Vernon?

The warmest month in Mt. Vernon is July (26.2 °C on average); the coldest is January (0.0 °C).

Q: How much does it rain in Mt. Vernon?

Mt. Vernon receives on average 1,060 mm of precipitation per year, spread over about 112 rainy days.

Q: Is it sunny in Mt. Vernon?

Mt. Vernon gets on average 9.1 hours of sunshine per day, roughly 3,322 hours per year over 1940-2025.

Mt. Vernon (United States) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 13.8 °C and it receives 1,060 mm of precipitation per year.

These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.

The warmest month is July (26.2 °C on average) and the coldest is January (0.0 °C). Rainfall peaks in April.

Mt. Vernon averages 77 frost days, 63 hot days (≥ 30 °C) and 112 rainy days per year.

Mt. Vernon has warmed by +1.4 °C between 1940 and 2025, or +0.16 °C per decade. This trend is statistically significant.

The number of frost days there went from about 87 to 67 per year over the period.

The hottest day of the period reached 41.3 °C (on 14 July 1954) and the coldest -28.2 °C (on 2 February 1951).

Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.

Climate normals · ERA5

Mt. VernonIllinois

coords: 38.32°, -88.90°
period: 1940–2025 · 86 yrs

CfaHumid subtropicalWarmest monthJulyColdest monthJanuaryWettest monthAprilDriest monthSeptember

Mean daily temperature

13.8°C

Average daily high

18.6°C

Average daily low

9.3°C

Annual rainfall

1,060mm

Sunshine / day

9.1h

Mean relative humidity

67%

Average peak wind

16.8km/h

Seasonal range

26.2°C

Frost days (< 0 °C)

77 d/yr

Hot days (≥ 30 °C)

63 d/yr

Rainy days (≥ 1 mm)

112 d/yr

Annual snowfall

33.2 cm

Average feels-like high

17.6 °C

Average feels-like low

7.3 °C

Average peak gust

36.4 km/h

Tropical nights (≥ 20 °C)

69 d/yr

Solar radiation

15.7 MJ/m²

Has the climate changed?

One stripe per year, 1940 to 2025

+1.4 °C

since 1940

+0.2 °C per decade · r² = 0.25 · p = < 0.001

19402025

Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).

A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.

Records for the period

Hottest day

41.3 °C

14 July 1954

Coldest day

-28.2 °C

2 February 1951

Wettest day

123 mm

8 May 1961

Windiest day

47.7 km/h

5 April 1947

Strongest gust

108.0 km/h

15 December 1971

Hottest feels-like

44.7 °C

25 August 2023

Coldest feels-like

-34.4 °C

20 January 1985

Snowiest day

22.6 cm

27 February 1984

Sunniest day

14.0 h

20 May 1940

Year	Hottest day	Coldest day	Annual mean	Rainfall	Hot days	Frost days
2025	36.0 °C29 July 2025	-16.8 °C15 January 2025	14.6 °C	1,163 mm	66	72
2024	36.2 °C27 August 2024	-18.4 °C14 January 2024	15.4 °C	1,205 mm	67	47
2023	38.0 °C25 August 2023	-9.1 °C31 January 2023	15.4 °C	1,170 mm	63	42
2022	36.8 °C5 July 2022	-21.7 °C23 December 2022	14.2 °C	1,179 mm	64	88
2021	36.6 °C12 June 2021	-17.8 °C19 February 2021	14.9 °C	1,141 mm	71	63
2020	36.1 °C10 August 2020	-14.6 °C14 February 2020	14.5 °C	1,246 mm	58	55
2019	35.0 °C10 July 2019	-18.2 °C30 January 2019	14.2 °C	1,463 mm	73	79
2018	35.3 °C5 July 2018	-18.8 °C1 January 2018	14.2 °C	1,427 mm	86	80
2017	36.8 °C22 July 2017	-15.9 °C27 December 2017	15.4 °C	1,030 mm	68	57
2016	35.9 °C16 June 2016	-15.2 °C19 December 2016	15.1 °C	1,238 mm	74	60
2015	34.8 °C29 July 2015	-20.5 °C19 February 2015	14.5 °C	1,312 mm	55	68
2014	34.4 °C23 August 2014	-22.6 °C7 January 2014	12.6 °C	1,113 mm	39	94
2013	37.0 °C31 August 2013	-18.9 °C12 December 2013	13.4 °C	996 mm	57	97
2012	40.9 °C28 June 2012	-12.5 °C30 December 2012	16.1 °C	831 mm	88	59
2011	37.6 °C1 September 2011	-16.6 °C21 January 2011	14.8 °C	1,561 mm	77	62
2010	38.2 °C4 August 2010	-15.9 °C10 January 2010	14.6 °C	834 mm	93	82
2009	36.1 °C25 June 2009	-18.1 °C16 January 2009	13.9 °C	1,248 mm	35	72
2008	35.5 °C20 July 2008	-15.0 °C22 December 2008	13.5 °C	1,267 mm	54	88
2007	39.3 °C15 August 2007	-14.3 °C5 February 2007	15.1 °C	850 mm	85	79
2006	35.5 °C18 July 2006	-13.9 °C19 February 2006	14.9 °C	1,111 mm	65	56
2005	35.8 °C30 June 2005	-16.0 °C9 December 2005	14.6 °C	943 mm	78	71
2004	35.0 °C13 July 2004	-16.6 °C30 January 2004	14.1 °C	1,129 mm	40	68
2003	35.8 °C27 August 2003	-16.5 °C24 January 2003	13.7 °C	1,025 mm	45	80
2002	37.3 °C4 August 2002	-14.5 °C6 December 2002	14.5 °C	1,101 mm	76	74
2001	35.0 °C7 July 2001	-14.3 °C2 January 2001	14.5 °C	1,049 mm	56	70
2000	35.9 °C29 August 2000	-21.4 °C25 December 2000	13.8 °C	1,015 mm	56	80
1999	39.4 °C30 July 1999	-21.9 °C5 January 1999	14.8 °C	893 mm	65	54
1998	35.5 °C19 July 1998	-12.2 °C30 December 1998	15.2 °C	1,264 mm	77	46
1997	37.6 °C26 July 1997	-21.0 °C13 January 1997	13.1 °C	1,118 mm	48	71
1996	35.7 °C30 June 1996	-21.8 °C4 February 1996	13.0 °C	1,267 mm	51	89
1995	37.9 °C18 August 1995	-14.9 °C9 December 1995	14.3 °C	926 mm	76	84
1994	35.7 °C19 June 1994	-26.1 °C19 January 1994	14.4 °C	1,031 mm	73	57
1993	35.6 °C27 July 1993	-18.5 °C18 February 1993	13.3 °C	1,339 mm	65	80
1992	35.4 °C13 July 1992	-17.3 °C16 January 1992	13.7 °C	936 mm	39	62
1991	37.4 °C2 August 1991	-13.0 °C15 February 1991	14.7 °C	1,071 mm	82	70
1990	37.3 °C9 July 1990	-15.3 °C23 December 1990	14.7 °C	1,316 mm	56	53
1989	35.7 °C7 July 1989	-26.5 °C22 December 1989	13.1 °C	1,110 mm	59	86
1988	38.8 °C25 June 1988	-15.5 °C6 February 1988	13.6 °C	1,005 mm	73	80
1987	37.6 °C3 August 1987	-11.5 °C24 January 1987	14.5 °C	996 mm	84	64
1986	36.8 °C25 July 1986	-18.3 °C27 January 1986	14.2 °C	1,052 mm	65	73
1985	35.6 °C13 July 1985	-26.5 °C20 January 1985	13.1 °C	1,536 mm	46	83
1984	35.5 °C13 June 1984	-23.3 °C19 January 1984	13.4 °C	1,297 mm	60	72
1983	40.2 °C23 July 1983	-22.7 °C25 December 1983	13.5 °C	1,187 mm	86	79
1982	35.5 °C4 August 1982	-24.0 °C10 January 1982	13.3 °C	1,231 mm	36	82
1981	35.6 °C13 July 1981	-19.5 °C12 February 1981	13.6 °C	1,114 mm	47	76
1980	40.3 °C12 July 1980	-17.3 °C2 February 1980	13.4 °C	914 mm	82	90
1979	35.0 °C6 August 1979	-22.5 °C14 January 1979	12.4 °C	1,228 mm	45	96
1978	36.7 °C1 July 1978	-17.6 °C26 January 1978	12.5 °C	1,018 mm	64	89
1977	36.5 °C5 June 1977	-27.7 °C17 January 1977	13.7 °C	1,127 mm	70	79
1976	36.0 °C22 July 1976	-18.4 °C8 January 1976	12.9 °C	737 mm	43	91
1975	35.4 °C12 August 1975	-14.1 °C9 February 1975	14.0 °C	1,051 mm	69	76
1974	35.9 °C19 July 1974	-18.0 °C12 January 1974	13.7 °C	1,075 mm	41	66
1973	34.5 °C25 August 1973	-20.4 °C21 December 1973	14.3 °C	1,236 mm	60	71
1972	34.5 °C18 August 1972	-21.2 °C16 January 1972	13.1 °C	941 mm	61	88
1971	36.5 °C26 June 1971	-16.5 °C9 February 1971	13.7 °C	861 mm	60	77
1970	37.1 °C2 July 1970	-21.9 °C21 January 1970	13.3 °C	885 mm	62	82
1969	36.0 °C5 July 1969	-15.1 °C4 January 1969	13.2 °C	933 mm	57	91
1968	36.0 °C20 August 1968	-20.4 °C7 January 1968	13.3 °C	1,045 mm	59	89
1967	33.8 °C25 May 1967	-17.1 °C25 February 1967	13.3 °C	1,106 mm	36	82
1966	41.1 °C13 July 1966	-20.7 °C30 January 1966	13.1 °C	882 mm	61	86
1965	38.1 °C24 July 1965	-18.9 °C31 January 1965	14.0 °C	786 mm	56	83
1964	38.8 °C3 August 1964	-20.4 °C14 January 1964	14.0 °C	826 mm	80	81
1963	35.9 °C3 August 1963	-21.9 °C23 January 1963	13.0 °C	716 mm	59	93
1962	38.5 °C20 August 1962	-21.4 °C10 January 1962	13.3 °C	894 mm	67	81
1961	34.8 °C29 July 1961	-20.9 °C28 January 1961	13.3 °C	1,052 mm	67	76
1960	36.6 °C6 September 1960	-19.0 °C5 March 1960	13.1 °C	689 mm	62	103
1959	35.7 °C29 June 1959	-18.0 °C4 January 1959	14.0 °C	898 mm	75	76
1958	34.5 °C8 June 1958	-19.8 °C17 February 1958	12.7 °C	916 mm	46	88
1957	36.3 °C17 July 1957	-15.6 °C16 January 1957	14.0 °C	1,277 mm	58	71
1956	37.4 °C5 August 1956	-15.4 °C26 January 1956	14.1 °C	961 mm	65	77
1955	35.6 °C9 September 1955	-20.3 °C11 February 1955	14.1 °C	1,064 mm	72	85
1954	41.3 °C14 July 1954	-13.4 °C12 January 1954	14.8 °C	811 mm	88	72
1953	39.3 °C20 June 1953	-13.1 °C23 December 1953	15.0 °C	663 mm	93	69
1952	40.6 °C29 June 1952	-13.9 °C29 January 1952	14.4 °C	791 mm	89	69
1951	37.1 °C30 August 1951	-28.2 °C2 February 1951	13.1 °C	1,229 mm	56	85
1950	35.5 °C26 June 1950	-19.6 °C18 December 1950	12.9 °C	1,520 mm	28	96
1949	35.7 °C1 July 1949	-15.3 °C30 January 1949	14.1 °C	1,199 mm	51	74
1948	35.6 °C24 August 1948	-19.9 °C28 January 1948	13.6 °C	1,146 mm	68	78
1947	40.0 °C6 August 1947	-14.2 °C5 February 1947	13.3 °C	838 mm	66	97
1946	35.7 °C19 July 1946	-13.5 °C27 January 1946	14.7 °C	1,044 mm	45	57
1945	37.4 °C24 July 1945	-17.1 °C20 December 1945	13.3 °C	1,480 mm	44	84
1944	37.6 °C28 June 1944	-11.0 °C13 February 1944	13.8 °C	815 mm	69	82
1943	39.9 °C26 August 1943	-15.1 °C14 February 1943	13.1 °C	649 mm	74	98
1942	37.0 °C1 August 1942	-20.7 °C10 January 1942	13.0 °C	879 mm	64	95
1941	36.8 °C11 August 1941	-13.7 °C20 February 1941	13.3 °C	808 mm	62	95
1940	36.7 °C30 July 1940	-24.6 °C19 January 1940	12.0 °C	841 mm	47	101

Normals computed over complete calendar years 1940–2025.

A specific year

Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?

Year

Across the whole year

Average daily high

19.6 °C

+1.0 °C

Hot days (≥ 30 °C)

66 d/yr

Frost days (< 0 °C)

72 d/yr

-5

Annual rainfall

1163 mm

+103 mm

Month by month

	High	vs. normal	Precipitation	vs. normal
Jan	2.4 °C	-1.7 °C	69 mm	-6 mm
Feb	6.6 °C	-0.2 °C	90 mm	+13 mm
Mar	17.8 °C	+5.1 °C	71 mm	-37 mm
Apr	21.2 °C	+2.0 °C	175 mm	+57 mm
May	23.4 °C	-1.0 °C	149 mm	+34 mm
Jun	29.8 °C	+0.4 °C	140 mm	+48 mm
Jul	31.8 °C	+0.8 °C	129 mm	+46 mm
Aug	29.8 °C	-0.4 °C	16 mm	-58 mm
Sep	28.9 °C	+2.2 °C	108 mm	+38 mm
Oct	22.2 °C	+1.8 °C	111 mm	+30 mm
Nov	14.1 °C	+1.7 °C	81 mm	-9 mm
Dec	7.1 °C	+0.7 °C	26 mm	-53 mm

The year's extremes

Hottest day

36.0 °C

29 Jul 2025

Coldest day

-16.8 °C

15 Jan 2025

Wettest day

45.0 mm

5 Apr 2025

Windiest day

38.9 km/h

19 Mar 2025

Strongest gust

87.1 km/h

14 Mar 2025

Hottest feels-like

42.0 °C

29 Jul 2025

Coldest feels-like

-21.5 °C

20 Feb 2025

Snowiest day

6.7 cm

10 Jan 2025

Sunniest day

14.0 h

21 May 2025

What was the weather like that day?

Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.

Date

Frequently asked questions

What is the climate of Mt. Vernon?

Mt. Vernon has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 13.8 °C and it receives 1,060 mm of precipitation per year.

What is the hottest day ever recorded in Mt. Vernon?

The hottest day measured in Mt. Vernon between 1940 and 2025 was 14 July 1954, reaching 41.3 °C.

What is the coldest day in Mt. Vernon?

The coldest day measured in Mt. Vernon between 1940 and 2025 was 2 February 1951, at -28.2 °C.

Does it snow in Mt. Vernon?

Yes. Mt. Vernon gets on average 33.2 cm of snow per year and has around 77 frost days.

Has the climate of Mt. Vernon warmed?

Yes: Mt. Vernon warmed by +1.4 °C between 1940 and 2025, a statistically significant trend.

What is the wettest day in Mt. Vernon?

The wettest day measured in Mt. Vernon between 1940 and 2025 was 8 May 1961, with 123 mm of rain in 24 hours.

What was the windiest day in Mt. Vernon?

The windiest day measured in Mt. Vernon between 1940 and 2025 was 5 April 1947, with winds reaching 47.7 km/h.

What is the warmest month in Mt. Vernon?

The warmest month in Mt. Vernon is July (26.2 °C on average); the coldest is January (0.0 °C).

How much does it rain in Mt. Vernon?

Mt. Vernon receives on average 1,060 mm of precipitation per year, spread over about 112 rainy days.

Is it sunny in Mt. Vernon?

Mt. Vernon gets on average 9.1 hours of sunshine per day, roughly 3,322 hours per year over 1940-2025.

What is the biggest single-day snowfall in Mt. Vernon?

The heaviest 24-hour snowfall measured in Mt. Vernon between 1940 and 2025 was 27 February 1984, with 22.6 cm.

Are there tropical nights in Mt. Vernon?

Yes: Mt. Vernon has on average 69 tropical nights per year (temperature staying above 20 °C), over 1940-2025.

What was the most extreme apparent temperature in Mt. Vernon?

In Mt. Vernon, between 1940 and 2025, the highest apparent temperature reached 44.7 °C on 25 August 2023, and the lowest was -34.4 °C on 20 January 1985.

Compare Mt. Vernon with another city

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