Whanganui – current water temperature and swimming conditions
This page provides information about the current water temperature at Whanganui in Manawatū–Whanganui. Here you can view recent temperature trends on a 30-day chart, check typical monthly water temperature ranges, and compare today’s reading with historical averages for this date. A 7-day water temperature forecast, local weather conditions, and an overview of swimming suitability are also included.
Current Water Temperature
The water temperature in Whanganui River at Whanganui today is 15°C.
Water Temperature in Whanganui River at Whanganui: Daily Trends, Historical Records, and Forecast
Water Temperature Over the Last 30 Days
Water temperatures in Whanganui have been on a steady rise over the past month and have continued to climb over the last week.
According to our forecast, the water temperature in Whanganui will be 9.9°C in the next 7 days. See the table below for daily data for the upcoming week.
Table of Daily Water Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| Jul 2 | 13.9°C | 9.2°C | |
| Jul 3 | 13.8°C | 9.2°C | |
| Jul 4 | 13.7°C | 9.2°C | |
| Jul 5 | 14.3°C | 9.2°C | |
| Jul 6 | 14.4°C | 9.2°C | |
| Jul 7 | 15.0°C | 9.2°C | |
| Jul 8 | 15.0°C | 9.2°C | |
| Jul 9 | 15.0°C | 9.2°C | |
| Jul 10 | 15.0°C | 9.2°C | 15.0°C |
| Jul 11 | 9.2°C | 14.3°C | |
| Jul 12 | 9.2°C | 13.6°C | |
| Jul 13 | 9.2°C | 12.8°C | |
| Jul 14 | 9.2°C | 12.1°C | |
| Jul 15 | 9.2°C | 11.4°C | |
| Jul 16 | 9.2°C | 10.7°C | |
| Jul 17 | 9.2°C | 9.9°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual river water temperatures may vary by several degrees from the reported values, particularly after heavy rainfall or periods of changing weather. Rainfall, river flow rates, and runoff from cooler upstream areas can significantly affect water temperature, especially in flowing sections and shaded stretches. Air temperature and cloud cover also play an important role, with warm, sunny conditions helping rivers warm up more quickly. As a result, noticeable temperature differences can occur along the same river.
Our forecast is based on a proprietary mathematical model that takes into account real-time river temperature changes, historical data, seasonal patterns, river flow conditions, recent rainfall, and local air temperature. We also factor in broader weather conditions specific to each region of New Zealand to improve accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Today | Yesterday | A Week Ago |
|---|---|---|---|
| January | 17°C | 22°C | 27°C |
| February | 13°C | 20°C | 27°C |
| March | 13°C | 19°C | 24°C |
| April | 10°C | 15°C | 19°C |
| May | 8°C | 12°C | 16°C |
| June | 4°C | 9°C | 14°C |
| July | 4°C | 9°C | 13°C |
| August | 6°C | 10°C | 13°C |
| September | 8°C | 12°C | 16°C |
| October | 10°C | 15°C | 19°C |
| November | 11°C | 17°C | 23°C |
| December | 14°C | 20°C | 25°C |
Whanganui: Weather Forecast
July 10
July 11
July 12
July 13
July 14
Location & Local Information
Whanganui sits near the lower reaches of the Whanganui River, where the river widens as it approaches the Tasman Sea. Water temperatures here reflect both inland influences and coastal moderation. In summer, the river near Whanganui typically reaches around 18–21 °C, which many people find comfortable for swimming during warm weather. Spring and autumn usually see temperatures in the range of 14–18 °C. In winter, the water cools to about 9–12 °C, making it feel cold and limiting time spent in the river.
Swimming Conditions
Swimming in the Whanganui River around Whanganui is allowed and is a popular summer activity, particularly at established access points and calmer stretches close to the riverbanks. During warm, settled weather, locals often swim to cool off, especially when river levels are stable. However, the river can carry strong currents, and conditions may change quickly after heavy rainfall upstream, affecting safety and water clarity. Cooler months generally see fewer swimmers due to lower temperatures and increased flow. For these reasons, swimming is best suited to summer and to locations known for safe access. Overall, Whanganui offers good seasonal swimming opportunities in the river, while for much of the year it is more commonly enjoyed as a scenic and cultural feature of the city rather than a regular swimming spot.