Buffalo Grove climate — normals and trends
Buffalo Grove (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 9.4 °C and it receives 896 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 (23.2 °C on average) and the coldest is January (-5.2 °C). Rainfall peaks in April.
Buffalo Grove averages 113 frost days, 14 hot days (≥ 30 °C) and 119 rainy days per year.
Buffalo Grove has warmed by +1.7 °C between 1940 and 2025, or +0.21 °C per decade. This trend is statistically significant.
The number of frost days there went from about 129 to 97 per year over the period.
The hottest day of the period reached 37.4 °C (on 14 July 1995) and the coldest -30.9 °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
Buffalo GroveIllinois
- coords
- 42.15°, -87.96°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.4°C
Average daily high
13.0°C
Average daily low
5.9°C
Annual rainfall
896mm
Sunshine / day
8.8h
Mean relative humidity
72%
Average peak wind
21.8km/h
Seasonal range
28.4°C
Frost days (< 0 °C)
113 d/yr
Hot days (≥ 30 °C)
14 d/yr
Rainy days (≥ 1 mm)
119 d/yr
Annual snowfall
81.1 cm
Average feels-like high
10.8 °C
Average feels-like low
2.5 °C
Average peak gust
40.0 km/h
Tropical nights (≥ 20 °C)
35 d/yr
Solar radiation
14.8 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.7 °C
since 1940
+0.2 °C per decade · r² = 0.30 · 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
37.4 °C
14 July 1995
Coldest day
-30.9 °C
3 February 1996
Wettest day
90 mm
13 September 2008
Windiest day
57.0 km/h
11 November 1940
Strongest gust
113.4 km/h
10 November 1998
Hottest feels-like
43.7 °C
6 July 2012
Coldest feels-like
-38.8 °C
20 January 1985
Snowiest day
24.8 cm
1 January 1948
Sunniest day
14.7 h
18 June 2022
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 | -1.5 °C | +0.4 °C | 29 mm | -25 mm |
| Feb | 0.2 °C | +0.4 °C | 30 mm | -17 mm |
| Mar | 10.2 °C | +5.1 °C | 93 mm | +20 mm |
| Apr | 12.8 °C | +1.4 °C | 74 mm | -25 mm |
| May | 15.8 °C | -2.0 °C | 94 mm | +2 mm |
| Jun | 25.0 °C | +0.8 °C | 105 mm | +18 mm |
| Jul | 27.1 °C | +0.2 °C | 113 mm | +29 mm |
| Aug | 25.3 °C | -0.8 °C | 61 mm | -21 mm |
| Sep | 23.5 °C | +1.2 °C | 41 mm | -33 mm |
| Oct | 17.2 °C | +1.4 °C | 60 mm | -13 mm |
| Nov | 8.8 °C | +1.1 °C | 62 mm | -7 mm |
| Dec | 0.6 °C | -0.5 °C | 65 mm | +3 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 Buffalo Grove?
Buffalo Grove has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 9.4 °C and it receives 896 mm of precipitation per year.
What is the hottest day ever recorded in Buffalo Grove?
The hottest day measured in Buffalo Grove between 1940 and 2025 was 14 July 1995, reaching 37.4 °C.
What is the coldest day in Buffalo Grove?
The coldest day measured in Buffalo Grove between 1940 and 2025 was 3 February 1996, at -30.9 °C.
Does it snow in Buffalo Grove?
Yes. Buffalo Grove gets on average 81.1 cm of snow per year and has around 113 frost days.
Has the climate of Buffalo Grove warmed?
Yes: Buffalo Grove warmed by +1.7 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Buffalo Grove?
The wettest day measured in Buffalo Grove between 1940 and 2025 was 13 September 2008, with 90 mm of rain in 24 hours.
What was the windiest day in Buffalo Grove?
The windiest day measured in Buffalo Grove between 1940 and 2025 was 11 November 1940, with winds reaching 57.0 km/h.
What is the warmest month in Buffalo Grove?
The warmest month in Buffalo Grove is July (23.2 °C on average); the coldest is January (-5.2 °C).
How much does it rain in Buffalo Grove?
Buffalo Grove receives on average 896 mm of precipitation per year, spread over about 119 rainy days.
Is it sunny in Buffalo Grove?
Buffalo Grove gets on average 8.8 hours of sunshine per day, roughly 3,212 hours per year over 1940-2025.
What is the biggest single-day snowfall in Buffalo Grove?
The heaviest 24-hour snowfall measured in Buffalo Grove between 1940 and 2025 was 1 January 1948, with 24.8 cm.
Are there tropical nights in Buffalo Grove?
Yes: Buffalo Grove has on average 35 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Buffalo Grove?
In Buffalo Grove, between 1940 and 2025, the highest apparent temperature reached 43.7 °C on 6 July 2012, and the lowest was -38.8 °C on 20 January 1985.
Compare Buffalo Grove with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Buffalo Grove