Macomb climate — normals and trends
Macomb (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 11.0 °C and it receives 939 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 (24.4 °C on average) and the coldest is January (-4.3 °C). Rainfall peaks in May.
Macomb averages 111 frost days, 39 hot days (≥ 30 °C) and 109 rainy days per year.
Macomb has warmed by +1.9 °C between 1940 and 2025, or +0.22 °C per decade. This trend is statistically significant.
The number of frost days there went from about 122 to 100 per year over the period.
The hottest day of the period reached 39.6 °C (on 7 July 2012) and the coldest -32.2 °C (on 3 February 1996).
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
MacombIllinois
- coords
- 40.46°, -90.67°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
11.0°C
Average daily high
15.9°C
Average daily low
6.2°C
Annual rainfall
939mm
Sunshine / day
8.9h
Mean relative humidity
70%
Average peak wind
19.0km/h
Seasonal range
28.7°C
Frost days (< 0 °C)
111 d/yr
Hot days (≥ 30 °C)
39 d/yr
Rainy days (≥ 1 mm)
109 d/yr
Annual snowfall
56.1 cm
Average feels-like high
14.3 °C
Average feels-like low
3.5 °C
Average peak gust
37.7 km/h
Tropical nights (≥ 20 °C)
39 d/yr
Solar radiation
15.3 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.9 °C
since 1940
+0.2 °C per decade · r² = 0.32 · p = < 0.001
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
39.6 °C
7 July 2012
Coldest day
-32.2 °C
3 February 1996
Wettest day
137 mm
5 August 2023
Windiest day
50.8 km/h
6 April 1997
Strongest gust
97.2 km/h
31 October 1979
Hottest feels-like
45.0 °C
13 July 1995
Coldest feels-like
-37.4 °C
20 January 1985
Snowiest day
22.5 cm
1 February 2011
Sunniest day
14.2 h
4 July 2025
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?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | -0.2 °C | -0.1 °C | 21 mm | -27 mm |
| Feb | 2.8 °C | +0.1 °C | 13 mm | -36 mm |
| Mar | 14.9 °C | +5.7 °C | 100 mm | +18 mm |
| Apr | 18.2 °C | +1.7 °C | 111 mm | +4 mm |
| May | 23.3 °C | +1.0 °C | 65 mm | -47 mm |
| Jun | 29.9 °C | +2.5 °C | 75 mm | -30 mm |
| Jul | 31.5 °C | +2.2 °C | 108 mm | +25 mm |
| Aug | 28.8 °C | +0.3 °C | 50 mm | -31 mm |
| Sep | 29.0 °C | +4.2 °C | 21 mm | -64 mm |
| Oct | 22.1 °C | +3.8 °C | 33 mm | -40 mm |
| Nov | 11.5 °C | +1.8 °C | 55 mm | -10 mm |
| Dec | 3.0 °C | +0.3 °C | 60 mm | +6 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Macomb?
Macomb has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 11.0 °C and it receives 939 mm of precipitation per year.
What is the hottest day ever recorded in Macomb?
The hottest day measured in Macomb between 1940 and 2025 was 7 July 2012, reaching 39.6 °C.
What is the coldest day in Macomb?
The coldest day measured in Macomb between 1940 and 2025 was 3 February 1996, at -32.2 °C.
Does it snow in Macomb?
Yes. Macomb gets on average 56.1 cm of snow per year and has around 111 frost days.
Has the climate of Macomb warmed?
Yes: Macomb warmed by +1.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Macomb?
The wettest day measured in Macomb between 1940 and 2025 was 5 August 2023, with 137 mm of rain in 24 hours.
What was the windiest day in Macomb?
The windiest day measured in Macomb between 1940 and 2025 was 6 April 1997, with winds reaching 50.8 km/h.
What is the warmest month in Macomb?
The warmest month in Macomb is July (24.4 °C on average); the coldest is January (-4.3 °C).
How much does it rain in Macomb?
Macomb receives on average 939 mm of precipitation per year, spread over about 109 rainy days.
Is it sunny in Macomb?
Macomb gets on average 8.9 hours of sunshine per day, roughly 3,249 hours per year over 1940-2025.
What is the biggest single-day snowfall in Macomb?
The heaviest 24-hour snowfall measured in Macomb between 1940 and 2025 was 1 February 2011, with 22.5 cm.
Are there tropical nights in Macomb?
Yes: Macomb has on average 39 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Macomb?
In Macomb, between 1940 and 2025, the highest apparent temperature reached 45.0 °C on 13 July 1995, and the lowest was -37.4 °C on 20 January 1985.
Compare Macomb with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Macomb