Cornwallis Beach – current water temperature and swimming conditions

Water Temperature in Cornwallis Beach: 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

Water temperatures in Cornwallis Beachfell over the past month, but have levelled out during the last week.

According to our forecast, Sea water temperature in Cornwallis Beach will be 17.8°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

Cornwallis Beach is located on the northern shores of the Manukau Harbour in the Auckland Region, facing the inner reaches of the Tasman Sea. Thanks to its sheltered harbour setting, the water here is generally calmer than on the exposed west coast beaches. In summer, particularly from January through March, water temperatures usually range between 19 and 22°C, which feels comfortable for most swimmers on a warm day. During autumn, temperatures tend to sit around 17 to 20°C. Winter brings cooler conditions, typically between 14 and 16°C, while spring sees a gradual rise from about 15 up to 18°C. Because the harbour is relatively shallow, the water can warm up quickly during settled, sunny periods.