Quincy climate — normals and trends
Quincy (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 11.9 °C and it receives 914 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 (25.3 °C on average) and the coldest is January (-3.2 °C). Rainfall peaks in May.
Quincy averages 102 frost days, 48 hot days (≥ 30 °C) and 105 rainy days per year.
Quincy has warmed by +1.6 °C between 1940 and 2025, or +0.19 °C per decade. This trend is statistically significant.
The number of frost days there went from about 114 to 90 per year over the period.
The hottest day of the period reached 40.6 °C (on 14 July 1954) and the coldest -31.3 °C (on 10 January 1942).
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
QuincyIllinois
- coords
- 39.94°, -91.41°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
11.9°C
Average daily high
16.8°C
Average daily low
7.1°C
Annual rainfall
914mm
Sunshine / day
9.0h
Mean relative humidity
69%
Average peak wind
17.7km/h
Seasonal range
28.5°C
Frost days (< 0 °C)
102 d/yr
Hot days (≥ 30 °C)
48 d/yr
Rainy days (≥ 1 mm)
105 d/yr
Annual snowfall
51.4 cm
Average feels-like high
15.4 °C
Average feels-like low
4.7 °C
Average peak gust
36.8 km/h
Tropical nights (≥ 20 °C)
50 d/yr
Solar radiation
15.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.6 °C
since 1940
+0.2 °C per decade · r² = 0.28 · 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
40.6 °C
14 July 1954
Coldest day
-31.3 °C
10 January 1942
Wettest day
103 mm
17 November 2015
Windiest day
50.6 km/h
27 March 1991
Strongest gust
99.4 km/h
20 November 1964
Hottest feels-like
45.1 °C
13 July 1995
Coldest feels-like
-36.6 °C
10 January 1942
Snowiest day
25.1 cm
1 February 2011
Sunniest day
14.3 h
27 June 1950
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 | 0.4 °C | -0.8 °C | 23 mm | -23 mm |
| Feb | 3.5 °C | -0.5 °C | 11 mm | -39 mm |
| Mar | 16.2 °C | +6.0 °C | 83 mm | +2 mm |
| Apr | 19.0 °C | +1.6 °C | 91 mm | -14 mm |
| May | 23.4 °C | +0.5 °C | 75 mm | -33 mm |
| Jun | 29.2 °C | +1.1 °C | 120 mm | +25 mm |
| Jul | 31.3 °C | +1.1 °C | 120 mm | +38 mm |
| Aug | 29.0 °C | -0.2 °C | 37 mm | -40 mm |
| Sep | 28.5 °C | +3.2 °C | 16 mm | -62 mm |
| Oct | 22.5 °C | +3.6 °C | 35 mm | -38 mm |
| Nov | 12.4 °C | +1.9 °C | 61 mm | -4 mm |
| Dec | 5.0 °C | +1.2 °C | 56 mm | +2 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 Quincy?
Quincy has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 11.9 °C and it receives 914 mm of precipitation per year.
What is the hottest day ever recorded in Quincy?
The hottest day measured in Quincy between 1940 and 2025 was 14 July 1954, reaching 40.6 °C.
What is the coldest day in Quincy?
The coldest day measured in Quincy between 1940 and 2025 was 10 January 1942, at -31.3 °C.
Does it snow in Quincy?
Yes. Quincy gets on average 51.4 cm of snow per year and has around 102 frost days.
Has the climate of Quincy warmed?
Yes: Quincy warmed by +1.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Quincy?
The wettest day measured in Quincy between 1940 and 2025 was 17 November 2015, with 103 mm of rain in 24 hours.
What was the windiest day in Quincy?
The windiest day measured in Quincy between 1940 and 2025 was 27 March 1991, with winds reaching 50.6 km/h.
What is the warmest month in Quincy?
The warmest month in Quincy is July (25.3 °C on average); the coldest is January (-3.2 °C).
How much does it rain in Quincy?
Quincy receives on average 914 mm of precipitation per year, spread over about 105 rainy days.
Is it sunny in Quincy?
Quincy gets on average 9.0 hours of sunshine per day, roughly 3,285 hours per year over 1940-2025.
What is the biggest single-day snowfall in Quincy?
The heaviest 24-hour snowfall measured in Quincy between 1940 and 2025 was 1 February 2011, with 25.1 cm.
Are there tropical nights in Quincy?
Yes: Quincy has on average 50 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Quincy?
In Quincy, between 1940 and 2025, the highest apparent temperature reached 45.1 °C on 13 July 1995, and the lowest was -36.6 °C on 10 January 1942.
Compare Quincy with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Quincy