Lake McKerrow – current water temperature and swimming conditions
This page provides information about the current water temperature at Lake McKerrow 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 McKerrow today is 13°C.
Water Temperature in Lake McKerrow: Daily Trends, Historical Records, and Forecast
⚠️ Lake temperatures between 10 and 15°C are cold but can be manageable for short swims on sunny, warm days. Shallow areas may feel slightly warmer, while deeper sections remain cold and slow to warm up. Most swimmers keep sessions brief, and wetsuits are often used for comfort. Wind and cooler air temperatures can quickly reduce how pleasant the swim feels.
Water Temperature Over the Last 30 Days
Water temperatures in Lake McKerrow 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 McKerrow will be 9.3°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 | 14.9°C | 8.7°C | |
| May 7 | 15.4°C | 8.7°C | |
| May 8 | 15.5°C | 8.7°C | |
| May 9 | 15.5°C | 8.7°C | |
| May 10 | 13.9°C | 8.7°C | |
| May 11 | 13.9°C | 8.7°C | |
| May 12 | 13.7°C | 8.7°C | |
| May 13 | 13.7°C | 8.7°C | |
| May 14 | 13.3°C | 8.7°C | 13.3°C |
| May 15 | 8.7°C | 12.7°C | |
| May 16 | 8.7°C | 12.2°C | |
| May 17 | 8.7°C | 11.6°C | |
| May 18 | 8.7°C | 11.0°C | |
| May 19 | 8.7°C | 10.4°C | |
| May 20 | 8.7°C | 9.9°C | |
| May 21 | 8.7°C | 9.3°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 | 16°C | 22°C |
| February | 10°C | 15°C | 20°C |
| March | 6°C | 12°C | 18°C |
| April | 5°C | 9°C | 13°C |
| May | 2°C | 6°C | 10°C |
| June | 0°C | 4°C | 8°C |
| July | 0°C | 4°C | 7°C |
| August | 0°C | 4°C | 7°C |
| September | 2°C | 7°C | 12°C |
| October | 4°C | 9°C | 13°C |
| November | 6°C | 12°C | 17°C |
| December | 8°C | 13°C | 18°C |
Lake McKerrow: Weather Forecast
May 15
May 16
May 17
May 18
May 19
Location & Local Information
Lake McKerrow, also known as Whakatipu Waitai, lies in northern Fiordland within the Southland Region. It is a long, tidal lake connected to the Tasman Sea via the Hollyford River, and surrounded by steep forested hills. Its water temperature reflects both alpine inflows and occasional tidal influence. In winter, surface temperatures are generally around 7–11°C. During spring, snowmelt and frequent rain keep the lake cool, typically between 9 and 13°C. In summer, particularly in January and February, sheltered near-shore areas may reach approximately 14–18°C on calm days, while deeper and tidally influenced sections remain cooler. By autumn, temperatures usually ease back to between 9 and 14°C. Weather and rainfall can quickly affect both temperature and clarity.
Swimming Conditions
Swimming is allowed, but it is uncommon due to the remote location and cool conditions. Even in mid-summer, the water can feel brisk, especially where tidal currents are present. The most suitable time for a short swim is during settled summer weather when temperatures approach the mid to high teens and winds are light. Swimmers should choose sheltered shoreline spots and avoid areas with noticeable current. Checking weather conditions beforehand helps ensure a safer and more comfortable experience in this isolated Fiordland setting.