Lake Poteriteri – current water temperature and swimming conditions
This page provides information about the current water temperature at Lake Poteriteri in Southland 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 Poteriteri today is 8°C.
Water Temperature in Lake Poteriteri: 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 Poteriteri 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 Poteriteri will be 8.5°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 |
|---|---|---|---|
| Aug 19 | 14.0°C | 8.6°C | |
| Aug 20 | 14.0°C | 8.6°C | |
| Aug 21 | 14.1°C | 8.6°C | |
| Aug 22 | 13.9°C | 8.6°C | |
| Aug 23 | 13.9°C | 8.6°C | |
| Aug 24 | 13.9°C | 8.6°C | |
| Aug 25 | 8.4°C | 8.6°C | |
| Aug 26 | 8.4°C | 8.6°C | |
| Aug 27 | 8.3°C | 8.6°C | 8.3°C |
| Aug 28 | 8.6°C | 8.3°C | |
| Aug 29 | 8.6°C | 8.4°C | |
| Aug 30 | 8.6°C | 8.4°C | |
| Aug 31 | 8.6°C | 8.4°C | |
| Sep 1 | 8.6°C | 8.4°C | |
| Sep 2 | 8.6°C | 8.5°C | |
| Sep 3 | 8.6°C | 8.5°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 | 11°C | 17°C | 22°C |
| February | 11°C | 18°C | 24°C |
| March | 10°C | 15°C | 20°C |
| April | 6°C | 11°C | 16°C |
| May | 5°C | 10°C | 14°C |
| June | 1°C | 7°C | 12°C |
| July | 2°C | 6°C | 10°C |
| August | 2°C | 7°C | 11°C |
| September | 5°C | 10°C | 14°C |
| October | 7°C | 11°C | 15°C |
| November | 9°C | 14°C | 18°C |
| December | 11°C | 17°C | 22°C |
Location & Local Information
Lake Poteriteri, in the Southland Region on the edge of Fiordland National Park, is a remote and scenic lake surrounded by native forest and rugged hills. Fed by rainfall and mountain streams, its water temperature reflects the cool southern climate and high rainfall of the area. In winter, surface temperatures are generally around 6–9°C. During spring, continued snowmelt and rain keep the lake cool, typically between 8 and 12°C. In summer, particularly in January and February, near-shore areas may warm to approximately 13–17°C on calm, sunny days, while deeper water remains colder. By autumn, temperatures usually ease back to between 8 and 13°C. Sudden weather changes can influence surface conditions.
Swimming Conditions
Swimming is allowed at Lake Poteriteri, but it is not commonly used for this purpose due to its remote location and cool water. Even in mid-summer, temperatures remain in the mid to high teens at best, so the water can feel brisk. The most manageable time for a short swim is during settled summer weather with light winds. Swimmers should choose sheltered shoreline spots and enter gradually to reduce the risk of cold shock. For most visitors, the lake is valued more for its wilderness setting than for recreational swimming.