Belfast has a temperate climate with warm summers and mild winters.
Temperatures peak in July and drop to their lowest in February, while rainfall is highest during autumn months.
Humidity remains high throughout the year, especially during winter months, creating warm and humid conditions.
| Month | 🌤️ | High | Low | Avg | Humid % | Rain (mm) | Wind (m/s) | Solar (kWh/m²) |
|---|---|---|---|---|---|---|---|---|
| January | ☔ | 11.0°C | 1.1°C | 6.0°C | 90% | 96 | 6.1 | 0.58 |
| February | 🌨️ | 10.4°C | 1.0°C | 5.7°C | 89% | 76 | 6.0 | 1.22 |
| March | 🌨️ | 11.6°C | 1.3°C | 6.5°C | 88% | 79 | 5.3 | 2.34 |
| April | 🌨️ | 13.6°C | 2.4°C | 8.0°C | 86% | 66 | 4.5 | 3.78 |
| May | 🌤️ | 16.8°C | 4.8°C | 10.8°C | 85% | 65 | 4.1 | 4.97 |
| June | 🌤️ | 18.9°C | 7.4°C | 13.2°C | 85% | 75 | 3.8 | 5.05 |
| July | 🌤️ | 20.1°C | 9.5°C | 14.8°C | 86% | 80 | 3.7 | 4.76 |
| August | ☔ | 19.5°C | 9.6°C | 14.6°C | 87% | 89 | 4.0 | 3.96 |
| September | ☔ | 18.3°C | 8.0°C | 13.2°C | 87% | 89 | 4.6 | 2.78 |
| October | ☔ | 15.8°C | 5.8°C | 10.8°C | 88% | 115 | 5.4 | 1.50 |
| November | ☔ | 13.4°C | 3.2°C | 8.3°C | 90% | 106 | 5.6 | 0.73 |
| December | ☔ | 11.7°C | 1.9°C | 6.8°C | 90% | 107 | 5.8 | 0.41 |
Showing average climate conditions across 45 years (1981–2025)
🧥 Light layers are sufficient — this Mild Winter stays cool without prolonged hard freezes.
🌤️ Conditions are ideal for outdoor activities throughout the day in this Mild Summer.
☔ Moderate 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 July, and gradually decline through autumn into winter.
These seasonal patterns offer comfortable conditions year-round, with warm summers and mild winters.
Monthly rainfall · 1981–2025 seasonal trends · mm/month
Rainfall is concentrated in the autumn months. Humidity stays high (around 88%), peaking during winter months, which creates warm and humid conditions.
☔ Moderate Rainfall expected — carry rain gear and plan outdoor activities around these months.
Monthly averages · 1981–2025
Across 45 years of records, Belfast's temperature has remained relatively stable over the past decade. Its hottest day reached 24.3°C in July 1983, and its coldest dropped to -2.7°C in January 1987. 2023 was the warmest year overall and 1986 the coolest.
The warmest year in Belfast's recorded history was 2023 (avg: 10.9°C), while the coldest was 1986 (avg: 8.7°C).
Average annual high/low · Last 30 years · °C
Total annual precipitation · Last 30 years · mm/year
| Year | Min Temp | Avg Temp | Max Temp | Rainfall (mm) | Avg Humidity | Avg Wind |
|---|---|---|---|---|---|---|
2025 🔥 | 5.4°C | 10.8°C | 16.2°C | 1020 | 87% | 4.7 m/s |
2024 | 5.5°C | 10.4°C | 15.3°C | 1039 | 88% | 4.9 m/s |
2023 | 5.7°C | 10.9°C | 16.1°C | 1228 | 88% | 4.7 m/s |
2022 | 5.7°C | 10.8°C | 15.9°C | 979 | 87% | 4.8 m/s |
2021 | 5.1°C | 10.4°C | 15.6°C | 1018 | 88% | 4.4 m/s |
2020 | 5.1°C | 10.2°C | 15.2°C | 1239 | 88% | 5.1 m/s |
2019 | 5.0°C | 10.2°C | 15.3°C | 1092 | 88% | 4.8 m/s |
2018 | 4.2°C | 9.9°C | 15.6°C | 1026 | 87% | 4.8 m/s |
2017 | 5.2°C | 10.1°C | 15.1°C | 1102 | 88% | 4.9 m/s |
2016 | 5.1°C | 10.1°C | 15.2°C | 1001 | 88% | 4.6 m/s |
Showing 1 to 10 of 45 years
Based on 45 years of data (1981–2025), July is typically the hottest month in Belfast, Northern Ireland, with average high temperatures around 20.1°C.
February is the coldest month in Belfast, with average low temperatures around 1.0°C.
October receives the most rainfall with approximately 115 mm, while May is the driest with 65 mm.
The highest recorded temperature was 24.3°C in July 1983. This is part of the historical record spanning 1981–2025.
The lowest recorded temperature was -2.7°C in January 1987.
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.
Belfast receives the most sunlight in June with an average solar radiation of 5.05 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning and agriculture in Northern Ireland.
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.
