McMahon's Beach – water temperature at Tweed River
This page provides up-to-date information about the water temperature at McMahon's Beach, located on the Tweed River in New South Wales. Here you can check current conditions, view recent temperature trends, explore typical monthly ranges, and compare today’s reading with historical averages for this date. The page also includes a 7-day water temperature forecast, local weather information, and swimming conditions.
Current Water Temperature
The water temperature in Tweed River at McMahon's Beach today is 19°C.
Water Temperature in Tweed River at McMahon's Beach: Daily Trends, Historical Records, and Forecast
⚠️ A river temperature of 15 to 20°C is generally considered cool to comfortable for swimming in Australia. On warm, calm days, this range allows for relaxed swimming and longer time in the water. Comfort depends heavily on air temperature and sunshine, as cooler weather can still make the water feel chilly. This range is popular for river swimming during spring and early autumn.
Water Temperature Over the Last 30 Days
While water temperatures in McMahon's Beach declined overall during the past month, they have shown a noticeable rebound over the last week.
According to our forecast, the water temperature in McMahon's Beach 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 | 18.3°C | 17.8°C | |
| Apr 29 | 18.2°C | 17.8°C | |
| Apr 30 | 18.0°C | 17.8°C | |
| May 1 | 18.0°C | 17.8°C | |
| May 2 | 18.0°C | 17.8°C | |
| May 3 | 17.8°C | 17.8°C | |
| May 4 | 17.8°C | 17.8°C | |
| May 5 | 17.7°C | 17.8°C | |
| May 6 | 18.7°C | 17.8°C | 18.7°C |
| May 7 | 17.8°C | 18.7°C | |
| May 8 | 17.8°C | 18.7°C | |
| May 9 | 17.8°C | 18.7°C | |
| May 10 | 17.8°C | 18.7°C | |
| May 11 | 17.8°C | 18.6°C | |
| May 12 | 17.8°C | 18.6°C | |
| May 13 | 17.8°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 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 Australia to improve accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Today | Yesterday | A Week Ago |
|---|---|---|---|
| January | 23°C | 26°C | 28°C |
| February | 22°C | 25°C | 28°C |
| March | 21°C | 24°C | 27°C |
| April | 18°C | 21°C | 24°C |
| May | 15°C | 18°C | 21°C |
| June | 14°C | 15°C | 17°C |
| July | 13°C | 15°C | 16°C |
| August | 14°C | 16°C | 19°C |
| September | 17°C | 19°C | 21°C |
| October | 19°C | 22°C | 24°C |
| November | 22°C | 24°C | 26°C |
| December | 23°C | 25°C | 27°C |
Location & Local Information
McMahon’s Beach sits along a quiet bend of the Tweed River in northern New South Wales, offering sheltered conditions that contrast with the open coast nearby. Water temperatures here reflect the region’s subtropical climate and are generally comfortable across much of the year. In summer, river temperatures typically rise to around 25–27 °C, making the water feel warm and inviting for long swims. Autumn often holds onto that warmth, with readings commonly between 23–25 °C and fairly stable conditions. Spring starts a little cooler at roughly 21–23 °C before warming steadily. Winter is the coolest period, but even then the river usually sits around 18–21 °C, which many locals still consider pleasant on sunny days.
Swimming Conditions
Swimming is allowed at McMahon’s Beach and is especially popular because of the calm river environment. With no ocean swell and generally gentle currents, it suits relaxed swimming and casual dips, particularly for those who prefer quieter water. The sheltered setting also means the river can feel slightly warmer than the nearby sea, adding to its appeal during the shoulder seasons. Swimmers should still stay aware of tides and occasional boat traffic, but overall McMahon’s Beach provides reliable water temperatures and easy swimming conditions for much of the year.