Whanganui in Summer
In summer (December, January and February), Whanganui sees average daytime highs around 19°C and overnight lows near 15°C, with 237 mm of rain over about 30 wet days across the season. It is the warmest season of the year and the driest season of the year.
Over the season highs climb from about 17°C in early December to 19°C by late February. The sky is clear or mostly clear about 36% of the time across summer, and the air most often feels dry.
Summer is Whanganui's best season of the year to visit on our travel score. For the whole year in context, see Whanganui's year-round climate.
- Avg daytime high
- 19°C
- warmest season of the year
- Avg overnight low
- 15°C
- Rainfall
- 237 mm
- 30 wet days
- Avg wind
- 21 km/h
- Travel score
- 6.1
- best season of the year
- Months
- Dec · Jan · Feb
Temperature in Whanganui in Summer
Over the season highs climb from about 17°C in early December to 19°C by late February.
A typical summer day in Whanganui reaches about 19°C and drops to 15°C overnight. The warmest of the three months is February, the coolest December.
Whanganui weather by month
How the three summer months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 19° / 15° | 71 | 9.3 | 14.5 | 6.3 |
| Feb | 20° / 16° | 66 | 8.1 | 13.6 | 6.5 |
| Mar | 18° / 15° | 68 | 9.6 | 12.3 | 6.2 |
| Apr | 17° / 13° | 98 | 11 | 11 | 5.2 |
| May | 15° / 11° | 97 | 12.4 | 9.8 | 4.3 |
| Jun | 13° / 10° | 109 | 14.1 | 9.2 | 3.2 |
| Jul | 12° / 9° | 105 | 14.3 | 9.5 | 2.9 |
| Aug | 12° / 9° | 102 | 14.7 | 10.4 | 3.0 |
| Sep | 13° / 10° | 97 | 13.6 | 11.7 | 3.4 |
| Oct | 14° / 11° | 107 | 14.2 | 13.1 | 3.8 |
| Nov | 16° / 12° | 89 | 12.2 | 14.2 | 4.6 |
| Dec | 17° / 14° | 100 | 12.7 | 14.8 | 5.4 |
Cloud cover in Summer
The sky is clear or mostly clear about 36% of the time across summer.
Chance of precipitation in Summer
Whanganui gets around 237 mm of rain over 30 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 21 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 36 min in early December to 13 hours by late February. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 6.5 kWh/m².
Is summer a good time to visit Whanganui?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit Whanganui for sightseeing.
What to pack for Whanganui in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Whanganui sees daytime highs around 19°C and nights near 15°C. Pack sun protection. Worth having: rain gear and a windbreaker. About 30 days see rain.
Sea temperature near Whanganui in Summer
The nearest coast averages about 18°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 16 km away) is warmest in February at about 19°C and coldest in August near 13°C.
The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 18 | 19 | 18 | 17 | 16 | 14 | 13 | 13 | 13 | 14 | 15 | 16 |
| Comfort | Cool | Cool | Cool | Cool | Cool | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 18 | Cool |
| Feb | 19 | Cool |
| Mar | 18 | Cool |
| Apr | 17 | Cool |
| May | 16 | Cool |
| Jun | 14 | Bracing |
| Jul | 13 | Bracing |
| Aug | 13 | Bracing |
| Sep | 13 | Bracing |
| Oct | 14 | Bracing |
| Nov | 15 | Bracing |
| Dec | 16 | Cool |
UV index in Whanganui in Summer
Clear-sky midday UV across summer averages around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Whanganui peaks around January 12 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 17 at about 2 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 12 | 11 | 7 | 5 | 2 | 2 | 2 | 3 | 4 | 7 | 10 | 11 |
| Level | Extreme | Extreme | High | Moderate | Moderate | Low | Moderate | Moderate | Moderate | High | Very high | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 12 | Extreme |
| Feb | 11 | Extreme |
| Mar | 7 | High |
| Apr | 5 | Moderate |
| May | 2 | Moderate |
| Jun | 2 | Low |
| Jul | 2 | Moderate |
| Aug | 3 | Moderate |
| Sep | 4 | Moderate |
| Oct | 7 | High |
| Nov | 10 | Very high |
| Dec | 11 | Extreme |
Where is Whanganui?
Whanganui sits at 39.9°S, 175.1°E, 18 m above sea level, in New Zealand. The nearest listed city is Palmerston North, 67 km away.
Topography around Whanganui
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Whanganui.
Within 3 km, the terrain around Whanganui has only modest variations in elevation — a maximum elevation change of 103 m around an average of 28 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 300 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,746 m.
The land around Whanganui is covered by grassland (39%), artificial surfaces (28%) and trees (25%) within 3 km, grassland (42%), water (32%) and trees (22%) within 16 km, and grassland (44%), trees (29%) and water (25%) within 80 km.
New Zealand travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type I
- 230 V · 50 Hz
- Prices
- ≈ 86% of US
- price level, 2025
- GDP per capita
- $49,591
- 2025
- Happiness
- 7.0 / 10
- World Happiness, 2025
- Safe drinking water
- 100%
- of population, 2024
- Homicide rate
- 1.5
- per 100k, 2022
- Road deaths
- 9.6
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Whanganui (-39.9333°, 175.05°, elevation 18 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.