Morton climate — normals and trends
Morton (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 953 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 (24.1 °C on average) and the coldest is January (-4.0 °C). Rainfall peaks in May.
Morton averages 109 frost days, 35 hot days (≥ 30 °C) and 112 rainy days per year.
Morton has warmed by +1.9 °C between 1940 and 2025, or +0.23 °C per decade. This trend is statistically significant.
The number of frost days there went from about 121 to 97 per year over the period.
The hottest day of the period reached 39.7 °C (on 7 July 2012) and the coldest -30.7 °C (on 20 January 1985).
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
MortonIllinois
- coords
- 40.61°, -89.46°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
11.0°C
Average daily high
15.9°C
Average daily low
6.3°C
Annual rainfall
953mm
Sunshine / day
8.9h
Mean relative humidity
70%
Average peak wind
19.6km/h
Seasonal range
28.1°C
Frost days (< 0 °C)
109 d/yr
Hot days (≥ 30 °C)
35 d/yr
Rainy days (≥ 1 mm)
112 d/yr
Annual snowfall
53.9 cm
Average feels-like high
14.2 °C
Average feels-like low
3.6 °C
Average peak gust
38.1 km/h
Tropical nights (≥ 20 °C)
38 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 = 0.35 · 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
39.7 °C
7 July 2012
Coldest day
-30.7 °C
20 January 1985
Wettest day
125 mm
9 September 1992
Windiest day
54.0 km/h
31 October 1979
Strongest gust
106.6 km/h
10 November 1998
Hottest feels-like
44.3 °C
13 July 1995
Coldest feels-like
-38.1 °C
20 January 1985
Snowiest day
21.0 cm
1 February 2011
Sunniest day
14.1 h
22 June 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 | -0.3 °C | -0.4 °C | 24 mm | -28 mm |
| Feb | 3.2 °C | +0.4 °C | 16 mm | -36 mm |
| Mar | 14.8 °C | +5.5 °C | 91 mm | +6 mm |
| Apr | 17.9 °C | +1.4 °C | 105 mm | -0 mm |
| May | 22.7 °C | +0.5 °C | 90 mm | -19 mm |
| Jun | 28.8 °C | +1.6 °C | 115 mm | +14 mm |
| Jul | 30.4 °C | +1.4 °C | 150 mm | +65 mm |
| Aug | 27.8 °C | -0.4 °C | 63 mm | -16 mm |
| Sep | 27.9 °C | +3.1 °C | 27 mm | -52 mm |
| Oct | 21.3 °C | +3.0 °C | 60 mm | -16 mm |
| Nov | 11.3 °C | +1.5 °C | 60 mm | -12 mm |
| Dec | 2.7 °C | -0.2 °C | 48 mm | -11 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 Morton?
Morton has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 11.0 °C and it receives 953 mm of precipitation per year.
What is the hottest day ever recorded in Morton?
The hottest day measured in Morton between 1940 and 2025 was 7 July 2012, reaching 39.7 °C.
What is the coldest day in Morton?
The coldest day measured in Morton between 1940 and 2025 was 20 January 1985, at -30.7 °C.
Does it snow in Morton?
Yes. Morton gets on average 53.9 cm of snow per year and has around 109 frost days.
Has the climate of Morton warmed?
Yes: Morton warmed by +1.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Morton?
The wettest day measured in Morton between 1940 and 2025 was 9 September 1992, with 125 mm of rain in 24 hours.
What was the windiest day in Morton?
The windiest day measured in Morton between 1940 and 2025 was 31 October 1979, with winds reaching 54.0 km/h.
What is the warmest month in Morton?
The warmest month in Morton is July (24.1 °C on average); the coldest is January (-4.0 °C).
How much does it rain in Morton?
Morton receives on average 953 mm of precipitation per year, spread over about 112 rainy days.
Is it sunny in Morton?
Morton 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 Morton?
The heaviest 24-hour snowfall measured in Morton between 1940 and 2025 was 1 February 2011, with 21.0 cm.
Are there tropical nights in Morton?
Yes: Morton has on average 38 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Morton?
In Morton, between 1940 and 2025, the highest apparent temperature reached 44.3 °C on 13 July 1995, and the lowest was -38.1 °C on 20 January 1985.
Compare Morton with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Morton