Greymouth – current water temperature and swimming conditions

Water Temperature in Greymouth: 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

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

According to our forecast, Sea water temperature in Greymouth will be 15.3°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

Greymouth is the largest town on the West Coast of the South Island, sitting at the mouth of the Grey River and facing the Tasman Sea. Sea temperatures here reflect the cool, energetic nature of this coastline. In winter, from June to August, the water generally ranges between 11–14°C, which feels distinctly cold and is usually only comfortable for surfers or swimmers wearing full wetsuits. Through spring, temperatures gradually rise to around 13–15°C. Summer, from December to March, brings the most settled conditions, with sea temperatures commonly sitting between 16–19°C during fine spells. Early autumn can still see 15–17°C before cooling again as winter approaches.