Rakaia River – current water temperature and swimming conditions
This page provides information about the current water temperature at Rakaia River in Canterbury Region. 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 Rakaia River today is 11°C.
Water Temperature in Rakaia River: Daily Trends, Historical Records, and Forecast
⚠️ River water between 10 and 15°C is cold but manageable for short swims, especially on sunny days with warm air temperatures. The moving nature of a river can make the water feel colder than the actual reading, particularly in shaded or deeper sections. Casual swimming is usually brief, with wetsuits often preferred. Windy or cool weather can significantly reduce comfort, even when the air temperature is mild.
Water Temperature Over the Last 30 Days
Water temperatures in Rakaia River have been gradually cooling over the past month, with a further drop recorded during the last week.
According to our forecast, the water temperature in Rakaia River will be 8.4°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 |
|---|---|---|---|
| May 6 | 11.0°C | 8.0°C | |
| May 7 | 11.0°C | 8.0°C | |
| May 8 | 12.6°C | 8.0°C | |
| May 9 | 12.6°C | 8.0°C | |
| May 10 | 12.6°C | 8.0°C | |
| May 11 | 12.6°C | 8.0°C | |
| May 12 | 12.6°C | 8.0°C | |
| May 13 | 11.4°C | 8.0°C | |
| May 14 | 10.9°C | 8.0°C | 10.9°C |
| May 15 | 8.0°C | 10.5°C | |
| May 16 | 8.0°C | 10.2°C | |
| May 17 | 8.0°C | 9.8°C | |
| May 18 | 8.0°C | 9.5°C | |
| May 19 | 8.0°C | 9.1°C | |
| May 20 | 8.0°C | 8.7°C | |
| May 21 | 8.0°C | 8.4°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 | 10°C | 15°C | 19°C |
| February | 9°C | 14°C | 19°C |
| March | 9°C | 14°C | 18°C |
| April | 6°C | 10°C | 14°C |
| May | 3°C | 8°C | 13°C |
| June | 2°C | 6°C | 10°C |
| July | 1°C | 5°C | 9°C |
| August | 2°C | 6°C | 10°C |
| September | 4°C | 8°C | 11°C |
| October | 4°C | 9°C | 13°C |
| November | 6°C | 11°C | 15°C |
| December | 8°C | 13°C | 17°C |
Rakaia River: Weather Forecast
May 15
May 16
May 17
May 18
May 19
Location & Local Information
Source Southern Alps Length 150 kilometres
The Rakaia River in the Canterbury Region is one of the South Island’s large braided rivers, flowing from the Southern Alps to the Pacific Ocean. Fed by alpine snow and glacier melt, its water remains cool throughout much of the year. In winter, temperatures are typically around 6–9°C, reflecting its mountain origins. During spring, snowmelt can keep the river chilly, generally between 8 and 12°C. In summer, especially in January and February, water temperatures in lower, slower-moving reaches may rise to around 14–18°C, though it often feels cooler due to the strong current. In autumn, temperatures usually sit between 10 and 15°C before dropping again as winter approaches. Sudden weather changes in the Alps can quickly affect both temperature and flow.
Swimming Conditions
Swimming is allowed in the Rakaia River, but it requires care and local knowledge. The river has powerful currents, shifting gravel channels and cold alpine water, even in summer. While some sheltered side braids and calm edges may be suitable for a brief dip when temperatures reach the mid to high teens, the main channel is generally not ideal for casual swimming. Conditions can change rapidly after rain or snowmelt, so checking river levels and exercising caution is essential before entering the water.