Nummi climate — normals and trends
Nummi (Finland) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 5.2 °C and it receives 676 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 (17.0 °C on average) and the coldest is February (-5.5 °C). Rainfall peaks in August.
Nummi averages 146 frost days, 0 hot days (≥ 30 °C) and 127 rainy days per year.
Nummi has warmed by +2.3 °C between 1940 and 2025, or +0.27 °C per decade. This trend is statistically significant.
The number of frost days there went from about 163 to 129 per year over the period.
The hottest day of the period reached 32.9 °C (on 17 July 2018) and the coldest -36.6 °C (on 10 January 1987).
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
NummiSouthwest Finland
- coords
- 60.46°, 22.31°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
5.2°C
Average daily high
8.6°C
Average daily low
1.7°C
Annual rainfall
676mm
Sunshine / day
7.7h
Mean relative humidity
81%
Average peak wind
17.2km/h
Seasonal range
22.5°C
Frost days (< 0 °C)
146 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
127 d/yr
Annual snowfall
107.2 cm
Average feels-like high
5.5 °C
Average feels-like low
-1.7 °C
Average peak gust
37.1 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
9.8 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.3 °C
since 1940
+0.3 °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
32.9 °C
17 July 2018
Coldest day
-36.6 °C
10 January 1987
Wettest day
72 mm
6 August 1967
Windiest day
45.7 km/h
26 December 2011
Strongest gust
101.2 km/h
14 January 1984
Hottest feels-like
33.9 °C
28 July 2019
Coldest feels-like
-42.9 °C
10 January 1987
Snowiest day
18.1 cm
12 January 2021
Sunniest day
18.0 h
22 June 2012
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 | +4.2 °C | 61 mm | +13 mm |
| Feb | 0.5 °C | +3.3 °C | 17 mm | -20 mm |
| Mar | 6.3 °C | +5.1 °C | 12 mm | -24 mm |
| Apr | 9.9 °C | +2.4 °C | 50 mm | +11 mm |
| May | 12.9 °C | -1.2 °C | 44 mm | +3 mm |
| Jun | 17.3 °C | -1.4 °C | 77 mm | +19 mm |
| Jul | 24.1 °C | +3.0 °C | 102 mm | +15 mm |
| Aug | 18.8 °C | -0.9 °C | 94 mm | +4 mm |
| Sep | 17.4 °C | +2.8 °C | 98 mm | +31 mm |
| Oct | 10.0 °C | +1.5 °C | 60 mm | +4 mm |
| Nov | 6.0 °C | +2.9 °C | 51 mm | -8 mm |
| Dec | 4.6 °C | +4.8 °C | 58 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 Nummi?
Nummi has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 5.2 °C and it receives 676 mm of precipitation per year.
What is the hottest day ever recorded in Nummi?
The hottest day measured in Nummi between 1940 and 2025 was 17 July 2018, reaching 32.9 °C.
What is the coldest day in Nummi?
The coldest day measured in Nummi between 1940 and 2025 was 10 January 1987, at -36.6 °C.
Does it snow in Nummi?
Yes. Nummi gets on average 107.2 cm of snow per year and has around 146 frost days.
Has the climate of Nummi warmed?
Yes: Nummi warmed by +2.3 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Nummi?
The wettest day measured in Nummi between 1940 and 2025 was 6 August 1967, with 72 mm of rain in 24 hours.
What was the windiest day in Nummi?
The windiest day measured in Nummi between 1940 and 2025 was 26 December 2011, with winds reaching 45.7 km/h.
What is the warmest month in Nummi?
The warmest month in Nummi is July (17.0 °C on average); the coldest is February (-5.5 °C).
How much does it rain in Nummi?
Nummi receives on average 676 mm of precipitation per year, spread over about 127 rainy days.
Is it sunny in Nummi?
Nummi gets on average 7.7 hours of sunshine per day, roughly 2,811 hours per year over 1940-2025.
What is the biggest single-day snowfall in Nummi?
The heaviest 24-hour snowfall measured in Nummi between 1940 and 2025 was 12 January 2021, with 18.1 cm.
Are there tropical nights in Nummi?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Nummi.
What was the most extreme apparent temperature in Nummi?
In Nummi, between 1940 and 2025, the highest apparent temperature reached 33.9 °C on 28 July 2019, and the lowest was -42.9 °C on 10 January 1987.
Compare Nummi with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Nummi