Herdsman Lake – current water temperature and swimming conditions
This page provides information about the current water temperature at Herdsman Lake in Western Australia. 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 Herdsman Lake today is 19°C.
Water Temperature in Herdsman Lake: Daily Trends, Historical Records, and Forecast
⚠️ A lake temperature of 15 to 20°C is considered cool to comfortable for swimming in Australia. On warm days with light winds, this range allows for relaxed swimming, especially in shallow or sheltered areas. Comfort depends strongly on air temperature and sunshine, as cooler or overcast weather can still make the water feel chilly. This range is common during spring and early summer.
Water Temperature Over the Last 30 Days
Water temperatures in Herdsman Lake 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 Herdsman Lake will be 18.6°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 |
|---|---|---|---|
| Apr 28 | 19.5°C | 18.7°C | |
| Apr 29 | 19.4°C | 18.7°C | |
| Apr 30 | 19.2°C | 18.7°C | |
| May 1 | 19.1°C | 18.7°C | |
| May 2 | 19.1°C | 18.7°C | |
| May 3 | 19.0°C | 18.7°C | |
| May 4 | 19.0°C | 18.7°C | |
| May 5 | 18.7°C | 18.7°C | |
| May 6 | 18.6°C | 18.7°C | 18.6°C |
| May 7 | 18.7°C | 18.6°C | |
| May 8 | 18.7°C | 18.6°C | |
| May 9 | 18.7°C | 18.6°C | |
| May 10 | 18.7°C | 18.6°C | |
| May 11 | 18.7°C | 18.6°C | |
| May 12 | 18.7°C | 18.6°C | |
| May 13 | 18.7°C | 18.6°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 Australia.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Today | Yesterday | A Week Ago |
|---|---|---|---|
| January | 20°C | 23°C | 32°C |
| February | 20°C | 23°C | 33°C |
| March | 20°C | 23°C | 33°C |
| April | 19°C | 20°C | 24°C |
| May | 16°C | 19°C | 20°C |
| June | 14°C | 20°C | 24°C |
| July | 14°C | 20°C | 24°C |
| August | 15°C | 20°C | 24°C |
| September | 14°C | 20°C | 24°C |
| October | 18°C | 21°C | 24°C |
| November | 20°C | 22°C | 33°C |
| December | 20°C | 23°C | 33°C |
Location & Local Information
Herdsman Lake is a large shallow wetland just north of Perth’s CBD, influenced by seasonal rainfall and the region’s Mediterranean climate. Because the lake is shallow, water temperatures respond quickly to air temperature and sunshine. In summer, the water can warm to around 20–25°C, sometimes feeling quite warm during extended hot spells. Spring and autumn are milder, with temperatures generally sitting between 16–20°C. In winter, water temperatures usually drop to about 12–15°C, giving the lake a cool feel, especially after cold nights or periods of rain. Wind and cloud cover can also cause noticeable day-to-day changes.
Swimming Conditions
Swimming in Herdsman Lake is not allowed and not recommended. The lake is managed as a protected wetland rather than a recreational swimming area, and water quality can be variable due to nutrient levels, urban runoff, and occasional algal growth. It is also an important habitat for birds and other wildlife, and human swimming would disturb the ecosystem. Even when summer temperatures appear suitable, the lack of designated access points and safety management makes swimming inappropriate. Overall, Herdsman Lake is best enjoyed for walking, cycling, and wildlife observation, with its seasonal water temperatures noted but swimming avoided in favour of safer, managed beaches and rivers elsewhere in the Perth area.