Dee Why Sea Temperature

Looking to find out what the sea water temperature in Dee Why is for today and the next few days? Below are data and charts that will give you information about sea temperatures in Dee Why and nearby locations.

Water temperature in Dee Why right now

Below is the current sea temperature for Dee Why, Australia on 13th July 2025.

17.76° C

(63.98° F)

  • yesterday: 17.74° C (63.94° F)
  • a week ago: 18.27° C (64.89° F)

At this temperature, water will feel cold compared to a swimming pool, but with a bit of experience and practice most people will find the water relatively comfortable to swim in.

The average sea temperature for Dee Why on July 13th over the last 10 years is 18.61° C (65.5° F), with a low temperature of 17.74° C (63.93° F) and a high of 19.65° C (67.37° F).

Analysis and forecast for Dee Why water temperatures

The water temperature in Dee Why today is lower than the average temperature of 18.61° C (65.5° F) and the temperature on this day last year, 13th July 2024, was 17.74° C (63.93° F).

The chart and table below shows the change in water temperature in Dee Why over the last 30 days:

Date Temperature (Celsius) Temperature (Fahrenheit)
July 13 17.76° C 63.98° F
July 12 17.74° C 63.94° F
July 10 18.42° C 65.16° F
July 9 18.34° C 65.01° F
July 8 18.33° C 64.99° F
July 7 18.25° C 64.85° F
July 6 18.27° C 64.89° F
July 5 18.4° C 65.12° F
July 4 18.48° C 65.26° F
July 3 18.94° C 66.09° F
July 2 18.64° C 65.55° F
July 1 19.39° C 66.9° F
June 30 19.19° C 66.54° F
June 29 19.19° C 66.54° F
June 28 19.2° C 66.56° F
June 27 19.45° C 67.01° F
June 26 19.4° C 66.92° F
June 25 19.39° C 66.9° F
June 24 19.03° C 66.25° F
June 23 18.75° C 65.75° F
June 22 18.65° C 65.57° F
June 21 18.5° C 65.3° F
June 20 18.35° C 65.03° F
June 19 18.16° C 64.69° F
June 18 18.33° C 64.99° F
June 17 18.49° C 65.28° F
June 16 18.6° C 65.48° F
June 15 18.64° C 65.55° F
June 14 18.7° C 65.66° F
June 13 18.76° C 65.77° F
June 12 18.75° C 65.75° F

The actual nearshore temperatures may vary by several degrees and this can also be heavily affected by weather. Strong winds can cause cold, deep waters to replace the surface waters that had been warmed by the sun, and heavy rain can also reduce the temperature of the sea surface temperature as well.

Water temperature in Dee Why by month

The chart below shows the monthly average water temperature in Dee Why.

For more detailed information on how the sea temperature in Dee Why changes for each month of the year, choose from the months below.

Dee Why map and nearby water temperatures

Locations near Dee Why

The highest temperature in Australia today is 26.62° C (79.92° F) in Weipa. The lowest is in Port Phillip Bay, where the temperature of the water is 11.18° C (52.13° F).

Why measure sea surface temperatures (SST) in Dee Why?

The ocean covers about 71% of the Earth's surface, and scientists record the sea surface temperature (SST) of locations such as Dee Why because they want to understand and learn how the ocean communicates with the atomosphere of Earth.

SST is one measure that provides information on the global climate, and it can be used to predict the weather in Dee Why as well as atmospheric model simulations and to study marine ecosystems in the area.

Data source and citation

Raw data for the calculations made to find the sea surface temperature in Dee Why comes from the National Oceanic and Atmospheric Administration (NOAA) and their 1/4° daily Optimum Interpolation Sea Surface Temperature.

The water temperature data is constructed by combining observations from different platforms (satellites, ships, buoys, and Argo floats) on a regular global grid. A spatially complete sea surface temperature map is then built by interpolating to fill in gaps in the data.

If you'd like to use any of the information above in the format it is presented, please use the citation tool below.

  • "Dee Why Sea Temperature". SeaTemperatures.net. Accessed on July 13, 2025. http://seatemperatures.net/australia-and-oceania/australia/dee-why/.

  • "Dee Why Sea Temperature". SeaTemperatures.net, http://seatemperatures.net/australia-and-oceania/australia/dee-why/. Accessed 13 July, 2025

  • Dee Why Sea Temperature. SeaTemperatures.net. Retrieved from http://seatemperatures.net/australia-and-oceania/australia/dee-why/.