Muroran climate — normals and trends
Muroran (Japan) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 7.8 °C and it receives 1,200 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 August (20.8 °C on average) and the coldest is January (-2.7 °C). Rainfall peaks in August.
Muroran averages 112 frost days, 0 hot days (≥ 30 °C) and 133 rainy days per year.
Muroran has warmed by +2.4 °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 133 to 91 per year over the period.
The hottest day of the period reached 28.9 °C (on 26 August 2023) and the coldest -11.9 °C (on 12 January 1961).
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
MuroranHokkaido
- coords
- 42.32°, 140.99°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
7.8°C
Average daily high
9.4°C
Average daily low
6.3°C
Annual rainfall
1,200mm
Sunshine / day
8.6h
Mean relative humidity
79%
Average peak wind
24.6km/h
Seasonal range
23.5°C
Frost days (< 0 °C)
112 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
133 d/yr
Annual snowfall
119.4 cm
Average feels-like high
6.9 °C
Average feels-like low
2.6 °C
Average peak gust
38.6 km/h
Tropical nights (≥ 20 °C)
19 d/yr
Solar radiation
13.5 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.4 °C
since 1940
+0.3 °C per decade · r² = 0.49 · 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
28.9 °C
26 August 2023
Coldest day
-11.9 °C
12 January 1961
Wettest day
151 mm
17 August 2016
Windiest day
82.8 km/h
30 August 2016
Strongest gust
137.2 km/h
30 August 2016
Hottest feels-like
36.2 °C
26 August 2023
Coldest feels-like
-21.6 °C
14 January 1967
Snowiest day
31.4 cm
21 March 1975
Sunniest day
14.9 h
9 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 | 1.8 °C | +3.0 °C | 44 mm | -8 mm |
| Feb | 2.0 °C | +3.0 °C | 38 mm | -9 mm |
| Mar | 4.2 °C | +2.5 °C | 83 mm | +21 mm |
| Apr | 8.2 °C | +2.8 °C | 130 mm | +42 mm |
| May | 13.2 °C | +2.9 °C | 66 mm | -39 mm |
| Jun | 19.0 °C | +4.0 °C | 114 mm | +5 mm |
| Jul | 23.9 °C | +4.5 °C | 96 mm | -50 mm |
| Aug | 25.1 °C | +3.0 °C | 157 mm | -13 mm |
| Sep | 22.5 °C | +2.6 °C | 274 mm | +105 mm |
| Oct | 15.0 °C | +1.4 °C | 75 mm | -36 mm |
| Nov | 9.8 °C | +3.5 °C | 134 mm | +53 mm |
| Dec | 4.4 °C | +3.3 °C | 122 mm | +60 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 Muroran?
Muroran has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 7.8 °C and it receives 1,200 mm of precipitation per year.
What is the hottest day ever recorded in Muroran?
The hottest day measured in Muroran between 1940 and 2025 was 26 August 2023, reaching 28.9 °C.
What is the coldest day in Muroran?
The coldest day measured in Muroran between 1940 and 2025 was 12 January 1961, at -11.9 °C.
Does it snow in Muroran?
Yes. Muroran gets on average 119.4 cm of snow per year and has around 112 frost days.
Has the climate of Muroran warmed?
Yes: Muroran warmed by +2.4 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Muroran?
The wettest day measured in Muroran between 1940 and 2025 was 17 August 2016, with 151 mm of rain in 24 hours.
What was the windiest day in Muroran?
The windiest day measured in Muroran between 1940 and 2025 was 30 August 2016, with winds reaching 82.8 km/h.
What is the warmest month in Muroran?
The warmest month in Muroran is August (20.8 °C on average); the coldest is January (-2.7 °C).
How much does it rain in Muroran?
Muroran receives on average 1,200 mm of precipitation per year, spread over about 133 rainy days.
Is it sunny in Muroran?
Muroran gets on average 8.6 hours of sunshine per day, roughly 3,139 hours per year over 1940-2025.
What is the biggest single-day snowfall in Muroran?
The heaviest 24-hour snowfall measured in Muroran between 1940 and 2025 was 21 March 1975, with 31.4 cm.
Are there tropical nights in Muroran?
Yes: Muroran has on average 19 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Muroran?
In Muroran, between 1940 and 2025, the highest apparent temperature reached 36.2 °C on 26 August 2023, and the lowest was -21.6 °C on 14 January 1967.
Compare Muroran with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Muroran