Second Wave: Understand Tidal Patterns

Overview of Tidal Patterns

What are tides?

• Tides are the regular rise and fall of sea levels caused by the gravitational pull of the moon and the sun, and the rotation of the Earth.

• On the Gold Coast (and most of Australia), we experience a semi-diurnal tide pattern — usually two high tides and two low tides every 24 hours.

Key terms:

• High Tide – Water at its highest level.

• Low Tide – Water at its lowest level.

• Incoming Tide (Flood) – The sea level rising, moving from low to high.

• Outgoing Tide (Ebb) – The sea level dropping, moving from high to low.

• Spring Tide – Extra high and low tides during full and new moons.

• Neap Tide – Milder tides during quarter moons.

How Tides Affect Surfing Conditions

• Wave Quality

  • Some breaks work best at low tide (sandbanks may be exposed, creating steep waves).

  • Others are better at high tide (deeper water over rocks or reefs softens the wave face).

• Wave Size & Power

  • Incoming tides can add push and energy to waves.

  • Outgoing tides sometimes flatten or weaken surf conditions.

• Safety

  • Low tide can expose rocks, reefs, and shallow sandbanks.

  • Rips can become stronger on the outgoing tide.

• Local Knowledge is Key

  • Every beach is different. For example:

    • Currumbin Alley often works best on a mid to high tide.

    • Duranbah can fire at low tide when sandbanks are shallow.

Practical Exercise: Reading Tide Charts

Find a Tide Chart

• Use apps like Magicseaweed, Coastalwatch, Surfline, or WillyWeather (Australia).

• Look for the high and low tide times and heights.

Identify the Pattern

• Notice the timing: when are the highs and lows?

• Note how much difference there is in water height between them.

Match to Surf Breaks

• Choose one local surf spot (e.g. Burleigh Heads).

• Research: Which tide does it work best on?

• Compare the tide chart with the best time to surf that spot.

Reflection Questions

• How might today’s tide pattern affect your surf session?

• What hazards could appear at low tide here?

• How could you use the incoming tide to your advantage?

Ket Takeaways

• Tides change the shape, size, and safety of surf conditions.

• Different surf breaks work best on different tides - there’s no “one size fits all.”

• Reading tide charts helps you plan sessions for optimal riding and safety.