Muroran has a temperate climate with warm summers and freezing winters.
Temperatures peak in August and drop to their lowest in February, while rainfall is highest during summer months.
Humidity remains high throughout the year creating cold and damp conditions.
| Month | 🌤️ | High | Low | Avg | Humid % | Rain (mm) | Wind (m/s) | Solar (kWh/m²) |
|---|---|---|---|---|---|---|---|---|
| January | ☔ | 3.2°C | -10.0°C | -3.4°C | 88% | 82 | 4.2 | 1.33 |
| February | ❄️ | 2.8°C | -10.4°C | -3.8°C | 86% | 65 | 4.2 | 2.04 |
| March | ❄️ | 6.6°C | -7.9°C | -0.7°C | 84% | 66 | 3.7 | 3.27 |
| April | 🌨️ | 13.1°C | -1.7°C | 5.7°C | 83% | 70 | 2.8 | 4.44 |
| May | ☔ | 17.9°C | 2.6°C | 10.2°C | 85% | 86 | 2.1 | 5.03 |
| June | ☔ | 21.7°C | 7.7°C | 14.7°C | 87% | 88 | 1.8 | 5.04 |
| July | ☔ | 25.2°C | 12.5°C | 18.9°C | 89% | 121 | 1.8 | 4.57 |
| August | 🌧️ | 26.5°C | 15.3°C | 20.9°C | 88% | 178 | 2.1 | 4.27 |
| September | ☔ | 24.0°C | 10.9°C | 17.4°C | 83% | 147 | 2.6 | 3.76 |
| October | ☔ | 19.3°C | 4.1°C | 11.7°C | 80% | 113 | 3.1 | 2.73 |
| November | ☔ | 14.0°C | -2.9°C | 5.6°C | 83% | 114 | 3.6 | 1.56 |
| December | ☔ | 7.8°C | -7.7°C | 0.1°C | 87% | 101 | 4.0 | 1.14 |
Showing average climate conditions across 45 years (1981–2025)
🧥 Pack heavy layers and prepare for snow — this is a Severe Winter destination.
🌤️ Conditions are ideal for outdoor activities throughout the day in this Mild Summer.
☔ Heavy Rainfall expected — carry rain gear and plan outdoor activities around these months.
Monthly averages · 1981–2025 climate normals · °C
Temperatures rise steadily from spring, peak in August, and gradually decline through autumn into winter.
These seasonal patterns make summer ideal for outdoor activities, while winters bring freezing conditions and heavy snowfall.
Monthly rainfall · 1981–2025 seasonal trends · mm/month
Monthly averages · 1981–2025
💧 Humidity peaks at 89% in July · annual avg 85%
The warmest year in Muroran's recorded history was 2025 (avg: 9.7°C), while the coldest was 1996 (avg: 7.1°C).
Average annual high/low · Last 10 years · °C
Total annual precipitation · Last 10 years · mm/year
| Year | Min Temp | Avg Temp | Max Temp | Rainfall (mm) | Avg Humidity | Avg Wind |
|---|---|---|---|---|---|---|
2025 🔥 🌧️ | 2.4°C | 9.7°C | 17.0°C | 1777 | 86% | 3.0 m/s |
2024 | 2.2°C | 9.4°C | 16.6°C | 1353 | 86% | 2.9 m/s |
2023 | 1.8°C | 9.3°C | 16.7°C | 1377 | 87% | 2.8 m/s |
2022 | 1.6°C | 8.3°C | 15.0°C | 1544 | 86% | 2.9 m/s |
2021 | 1.2°C | 8.8°C | 16.4°C | 1502 | 86% | 3.1 m/s |
2020 | 1.7°C | 8.5°C | 15.3°C | 1271 | 86% | 2.9 m/s |
2019 | 1.3°C | 8.7°C | 16.1°C | 1114 | 85% | 3.0 m/s |
2018 | 1.0°C | 8.5°C | 16.1°C | 1582 | 86% | 3.0 m/s |
2017 | 0.6°C | 7.8°C | 14.9°C | 1287 | 86% | 2.9 m/s |
2016 | 0.6°C | 7.9°C | 15.3°C | 1554 | 86% | 3.1 m/s |
Showing 1 to 10 of 45 years
Based on 45 years of data (1981–2025), August is typically the hottest month in Muroran, Hokkaidō, with average high temperatures around 26.5°C.
February is the coldest month in Muroran, with average low temperatures around -10.4°C.
August receives the most rainfall with approximately 178 mm, while February is the driest with 65 mm.
The highest recorded temperature was 29.3°C in August 1999. This is part of the historical record spanning 1981–2025.
The lowest recorded temperature was -14.1°C in January 2003.
This page covers 45 years of climate data from 1981 to 2025. As new data is added to the database the page automatically reflects the updated coverage.
Muroran receives the most sunlight in June with an average solar radiation of 5.04 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning and agriculture in Hokkaidō.
All climate data is sourced from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite and model data. It provides monthly averages for temperature, precipitation, humidity, wind speed, and solar radiation.
All weather data is sourced from NASA POWER (Prediction of Worldwide Energy Resources), a NASA project providing solar and meteorological data for renewable energy, building efficiency, and agricultural research.
