Ostrołęka climate — normals and trends
Ostrołęka (Poland) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 7.8 °C and it receives 630 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 (18.4 °C on average) and the coldest is January (-3.2 °C). Rainfall peaks in July.
Ostrołęka averages 108 frost days, 4 hot days (≥ 30 °C) and 130 rainy days per year.
Ostrołęka has warmed by +2.5 °C between 1940 and 2025, or +0.29 °C per decade. This trend is statistically significant.
The number of frost days there went from about 126 to 90 per year over the period.
The hottest day of the period reached 36.3 °C (on 8 August 2013) and the coldest -32.3 °C (on 11 January 1950).
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
OstrołękaMazovia
- coords
- 53.09°, 21.58°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
7.8°C
Average daily high
11.4°C
Average daily low
4.1°C
Annual rainfall
630mm
Sunshine / day
7.1h
Mean relative humidity
79%
Average peak wind
18.0km/h
Seasonal range
21.6°C
Frost days (< 0 °C)
108 d/yr
Hot days (≥ 30 °C)
4 d/yr
Rainy days (≥ 1 mm)
130 d/yr
Annual snowfall
65.5 cm
Average feels-like high
8.6 °C
Average feels-like low
0.9 °C
Average peak gust
35.5 km/h
Tropical nights (≥ 20 °C)
1 d/yr
Solar radiation
10.3 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.5 °C
since 1940
+0.3 °C per decade · r² = 0.42 · 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
36.3 °C
8 August 2013
Coldest day
-32.3 °C
11 January 1950
Wettest day
69 mm
3 September 1995
Windiest day
52.6 km/h
3 November 1981
Strongest gust
108.7 km/h
2 November 1981
Hottest feels-like
37.1 °C
31 July 1994
Coldest feels-like
-37.7 °C
11 January 1950
Snowiest day
23.2 cm
30 January 1979
Sunniest day
16.2 h
23 June 2019
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 | 4.0 °C | +5.1 °C | 47 mm | +7 mm |
| Feb | 1.8 °C | +1.5 °C | 12 mm | -26 mm |
| Mar | 11.2 °C | +6.2 °C | 34 mm | -2 mm |
| Apr | 16.3 °C | +4.3 °C | 32 mm | -15 mm |
| May | 15.7 °C | -2.1 °C | 72 mm | +9 mm |
| Jun | 22.5 °C | +1.2 °C | 56 mm | -16 mm |
| Jul | 24.0 °C | +1.1 °C | 123 mm | +41 mm |
| Aug | 23.6 °C | +1.0 °C | 38 mm | -27 mm |
| Sep | 20.1 °C | +2.3 °C | 91 mm | +38 mm |
| Oct | 11.6 °C | 0.0 °C | 53 mm | +9 mm |
| Nov | 5.8 °C | +0.7 °C | 50 mm | +4 mm |
| Dec | 3.9 °C | +2.8 °C | 17 mm | -28 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 Ostrołęka?
Ostrołęka has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 7.8 °C and it receives 630 mm of precipitation per year.
What is the hottest day ever recorded in Ostrołęka?
The hottest day measured in Ostrołęka between 1940 and 2025 was 8 August 2013, reaching 36.3 °C.
What is the coldest day in Ostrołęka?
The coldest day measured in Ostrołęka between 1940 and 2025 was 11 January 1950, at -32.3 °C.
Does it snow in Ostrołęka?
Yes. Ostrołęka gets on average 65.5 cm of snow per year and has around 108 frost days.
Has the climate of Ostrołęka warmed?
Yes: Ostrołęka warmed by +2.5 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Ostrołęka?
The wettest day measured in Ostrołęka between 1940 and 2025 was 3 September 1995, with 69 mm of rain in 24 hours.
What was the windiest day in Ostrołęka?
The windiest day measured in Ostrołęka between 1940 and 2025 was 3 November 1981, with winds reaching 52.6 km/h.
What is the warmest month in Ostrołęka?
The warmest month in Ostrołęka is July (18.4 °C on average); the coldest is January (-3.2 °C).
How much does it rain in Ostrołęka?
Ostrołęka receives on average 630 mm of precipitation per year, spread over about 130 rainy days.
Is it sunny in Ostrołęka?
Ostrołęka gets on average 7.1 hours of sunshine per day, roughly 2,592 hours per year over 1940-2025.
What is the biggest single-day snowfall in Ostrołęka?
The heaviest 24-hour snowfall measured in Ostrołęka between 1940 and 2025 was 30 January 1979, with 23.2 cm.
Are there tropical nights in Ostrołęka?
Yes: Ostrołęka has on average 1 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Ostrołęka?
In Ostrołęka, between 1940 and 2025, the highest apparent temperature reached 37.1 °C on 31 July 1994, and the lowest was -37.7 °C on 11 January 1950.
Compare Ostrołęka with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Ostrołęka