Lake Alexandrina – current water temperature and swimming conditions
This page provides information about the current water temperature at Lake Alexandrina 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 Lake Alexandrina today is 10°C.
Water Temperature in Lake Alexandrina: Daily Trends, Historical Records, and Forecast
❌ Lake water below 10°C is extremely cold and generally unsuitable for swimming for most people. Even during warm weather, deep lakes retain cold water, making entry uncomfortable and limiting time in the water. Swimming at this temperature is usually limited to quick dips or cold-water enthusiasts. Cool air temperatures or cloudy conditions can make lake swimming particularly harsh.
Water Temperature Over the Last 30 Days
Water temperatures in Lake Alexandrina 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 Lake Alexandrina will be 7.4°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 | 10.2°C | 7.0°C | |
| May 7 | 10.2°C | 7.0°C | |
| May 8 | 11.6°C | 7.0°C | |
| May 9 | 11.6°C | 7.0°C | |
| May 10 | 11.5°C | 7.0°C | |
| May 11 | 11.5°C | 7.0°C | |
| May 12 | 11.4°C | 7.0°C | |
| May 13 | 10.3°C | 7.0°C | |
| May 14 | 9.8°C | 7.0°C | 9.8°C |
| May 15 | 7.0°C | 9.5°C | |
| May 16 | 7.0°C | 9.1°C | |
| May 17 | 7.0°C | 8.8°C | |
| May 18 | 7.0°C | 8.4°C | |
| May 19 | 7.0°C | 8.1°C | |
| May 20 | 7.0°C | 7.7°C | |
| May 21 | 7.0°C | 7.4°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual lake water temperatures may differ from the reported values by several degrees, particularly during periods of strong winds or rapid weather changes. Wind can mix surface and deeper layers in a lake, bringing cooler water to the surface, while shallow areas may warm more quickly under direct sunlight. Air temperature, sunshine, and cloud cover strongly influence how quickly a lake heats up or cools down. These factors can lead to noticeable temperature variations across different parts of the lake.
Our forecast is based on a proprietary mathematical model that considers real-time lake temperature observations, historical trends, seasonal cycles, wind strength and direction, and region-specific air temperature. To enhance accuracy, we also incorporate data from nearby monitored locations and comparable lakes within New Zealand.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Today | Yesterday | A Week Ago |
|---|---|---|---|
| January | 9°C | 14°C | 19°C |
| February | 9°C | 15°C | 21°C |
| March | 7°C | 13°C | 19°C |
| April | 4°C | 10°C | 16°C |
| May | 2°C | 7°C | 12°C |
| June | 0°C | 4°C | 8°C |
| July | 0°C | 4°C | 7°C |
| August | 0°C | 4°C | 7°C |
| September | 3°C | 7°C | 11°C |
| October | 4°C | 9°C | 13°C |
| November | 6°C | 11°C | 15°C |
| December | 8°C | 13°C | 17°C |
Lake Alexandrina: Weather Forecast
May 15
May 16
May 17
May 18
May 19
May 20
Location & Local Information
Lake Alexandrina, in the Canterbury Region near Lake Tekapo, is a clear alpine lake set against a backdrop of the Southern Alps. At an elevation of around 700 metres, its water temperature reflects both altitude and glacial influences from the surrounding high country. In winter, surface temperatures are generally around 3–7°C, and ice can occasionally form along the edges. During spring, snowmelt keeps the lake cold, typically between 5 and 10°C. In summer, particularly in January and February, sheltered near-shore areas may warm to approximately 11–17°C on calm, sunny days, while deeper water remains noticeably cooler. By autumn, temperatures usually ease back to between 6 and 11°C. Wind can quickly affect surface conditions in this open basin.
Swimming Conditions
Swimming is allowed at Lake Alexandrina, and it is sometimes enjoyed during the warmer months. However, even in mid-summer the water can feel brisk due to its alpine origin. The most comfortable conditions are typically on calm, sunny days when near-shore temperatures reach the mid teens. Swimmers should choose sheltered spots and enter gradually to reduce the risk of cold shock. Checking weather conditions beforehand is advisable, as sudden changes and strong winds are common in this high country setting.