Local Winds

Sea Breeze

A sea breeze is a local wind that blows from the sea towards the land during the day.

It develops because the land heats faster than the sea.

• Air over the land warms, becomes less dense and rises.
• This produces relatively lower pressure over the land.
• Cooler, denser air from over the sea moves inland to replace it.

Typical Sea Breeze Characteristics

A sea breeze:

• usually begins during the late morning;
• is strongest during the afternoon;
• generally dies away during the evening;
• commonly reaches around 10–15 knots;
• may extend 25–40 km inland;
• may extend vertically to around 2,000–3,000 ft.

It is generally strongest on warm, sunny days, particularly in summer.

Cloud and Turbulence

A sea breeze may produce:

• fair-weather cumulus over the land;
• local turbulence from hills, trees, cliffs and other obstacles.

Rain is not normally associated with a simple sea breeze, although showers may occur if the atmosphere is sufficiently unstable.

Remember:

Daytime + warm land + wind onshore = Sea Breeze

Land Breeze

A land breeze is the opposite of a sea breeze.

It blows from the land towards the sea, usually during the night or early morning.