Diamond Head – current water temperature and swimming conditions

Water Temperature in Diamond Head: Daily Trends, Historical Records, and Forecast

⚠️ Water in this range feels cool but still manageable for many swimmers. Short to moderate swims are comfortable, especially in warm weather. Some people may prefer a wetsuit for longer stays, particularly when swimming actively or outside peak summer conditions.

It’s important to note that these swimming tips and recommendations apply only in settled weather. When air temperatures drop below 20°C — and sometimes even below 25°C — swimming can feel uncomfortable, even when water temperatures are relatively high.

Water Temperature Over the Last 30 Days

While water temperatures in Diamond Head declined overall during the past month, they have shown a noticeable rebound over the last week.

According to our forecast, Sea water temperature in Diamond Head will be 20.4°C in the next 7 days. See the table below for daily data for the upcoming week.

Table of Daily Sea Temperature Data

Annual Water Temperature Overview by Month

Monthly Water Temp Ranges

30°C

25°C

20°C

15°C

10°c

5°C

0°C

Annual Water Temperature Trend

Diamond Head, on the Mid North Coast of New South Wales near Port Macquarie, faces the open Tasman Sea and experiences clear seasonal changes in water temperature. During summer, the ocean is at its warmest, usually ranging from about 22–26 °C, which suits long swims and plenty of time in the water. Autumn brings a gradual cooling, with temperatures commonly around 20–23 °C. Winter is cooler but still manageable for many swimmers, with the sea typically sitting between 17–20 °C. In spring, the water slowly warms again from roughly 18 °C into the low twenties as conditions become more settled.