Whanganui has a warm temperate climate with warm summers and mild winters.
Temperatures peak in February and drop to their lowest in August, while rainfall is highest during summer months.
Humidity remains high throughout the year creating warm and humid conditions.
| Month | 🌤️ | High | Low | Avg | Humid % | Rain (mm) | Wind (m/s) | Solar (kWh/m²) |
|---|---|---|---|---|---|---|---|---|
| January | ☀️ | 25.3°C | 10.9°C | 18.1°C | 76% | 65 | 4.6 | 6.47 |
| February | ☀️ | 25.5°C | 11.5°C | 18.5°C | 76% | 69 | 4.2 | 5.67 |
| March | ☀️ | 24.3°C | 10.1°C | 17.2°C | 78% | 70 | 4.3 | 4.46 |
| April | ☔ | 21.5°C | 8.2°C | 14.9°C | 81% | 82 | 4.3 | 3.16 |
| May | ☔ | 18.9°C | 6.5°C | 12.7°C | 84% | 92 | 4.6 | 2.10 |
| June | ☔ | 16.4°C | 5.1°C | 10.8°C | 86% | 104 | 4.7 | 1.63 |
| July | ☔ | 15.1°C | 4.3°C | 9.7°C | 86% | 98 | 4.7 | 1.82 |
| August | ☔ | 15.4°C | 4.2°C | 9.8°C | 85% | 88 | 4.5 | 2.56 |
| September | ☔ | 17.1°C | 5.1°C | 11.1°C | 84% | 90 | 4.9 | 3.57 |
| October | ☔ | 18.8°C | 6.0°C | 12.4°C | 82% | 92 | 5.1 | 4.60 |
| November | 🌤️ | 20.7°C | 7.7°C | 14.2°C | 80% | 79 | 5.0 | 5.75 |
| December | ☔ | 23.0°C | 9.7°C | 16.4°C | 79% | 87 | 4.6 | 6.16 |
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 February, 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
Monthly averages · 1981–2025
💧 Humidity peaks at 86% in July · annual avg 81%
The warmest year in Whanganui's recorded history was 1998 (avg: 14.7°C), while the coldest was 1992 (avg: 12.4°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 | 8.1°C | 14.5°C | 21.0°C | 1106 | 82% | 4.6 m/s |
2024 | 7.6°C | 13.9°C | 20.1°C | 1009 | 83% | 4.5 m/s |
2023 | 7.8°C | 14.0°C | 20.2°C | 1311 | 85% | 4.5 m/s |
2022 🌧️ | 7.7°C | 14.3°C | 21.0°C | 1691 | 84% | 4.4 m/s |
2021 | 7.9°C | 14.1°C | 20.3°C | 1220 | 83% | 4.6 m/s |
2020 | 7.2°C | 13.7°C | 20.2°C | 1056 | 82% | 4.7 m/s |
2019 | 8.0°C | 14.2°C | 20.4°C | 1119 | 82% | 4.8 m/s |
2018 | 8.0°C | 14.3°C | 20.5°C | 1286 | 83% | 4.4 m/s |
2017 | 7.7°C | 13.9°C | 20.1°C | 1262 | 83% | 4.5 m/s |
2016 | 7.8°C | 14.2°C | 20.6°C | 1013 | 81% | 4.9 m/s |
Showing 1 to 10 of 45 years
Based on 45 years of data (1981–2025), February is typically the hottest month in Whanganui, Manawatu-Wanganui, with average high temperatures around 25.5°C.
August is the coldest month in Whanganui, with average low temperatures around 4.2°C.
June receives the most rainfall with approximately 104 mm, while January is the driest with 65 mm.
The highest recorded temperature was 30.2°C in January 2008. This is part of the historical record spanning 1981–2025.
The lowest recorded temperature was 2.2°C in July 1986.
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.
Whanganui receives the most sunlight in January with an average solar radiation of 6.47 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning and agriculture in Manawatu-Wanganui.
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.
