Onaero – current water temperature and swimming conditions

Water Temperature in Onaero: Daily Trends, Historical Records, and Forecast

⚠️ This is cool water that may feel brisk on entry. Swimming is usually limited to short sessions, and prolonged stays can become uncomfortable without thermal protection. Many swimmers choose a wetsuit, especially for surfing or open-water swimming.

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 Onaero have been gradually cooling over the past month, with a further drop recorded during the last week.

According to our forecast, Sea water temperature in Onaero will be 16.8°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

Onaero is a small coastal settlement north of New Plymouth in the Taranaki Region, facing the Tasman Sea. Sea temperatures here follow the typical west coast pattern, with noticeable seasonal variation. In winter, from June to August, the water generally ranges between 11–14°C, which feels distinctly cold and is usually best suited to surfers or swimmers wearing full wetsuits. Through spring, temperatures gradually lift to around 13–15°C. Summer, from December to March, brings the most inviting conditions, with sea temperatures commonly sitting between 16–19°C during settled, sunny spells. Early autumn can still see 15–17°C before cooling again as winter approaches.