Guilderton – current water temperature and swimming conditions

Water Temperature in Guilderton: 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 Guilderton 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 Guilderton will be 19.7°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

Guilderton sits at the mouth of the Moore River on Perth’s City Coast, where freshwater meets the Indian Ocean and creates a mix of ocean and estuary-style swimming conditions. Sea temperatures here follow the northern Perth pattern and are comfortable for swimming for much of the year. In summer, from December to February, the ocean usually sits around 21–24°C, feeling warm and inviting on sunny days. Autumn remains pleasant at roughly 19–22°C, while winter cools to about 16–18°C, which can feel brisk but is still suitable for shorter swims. Spring brings a gradual warm-up again, generally ranging between 18–21°C as air temperatures rise.