What Is a Land Breeze?

A land breeze is a local nighttime and early morning wind that occurs along coasts and blows offshore (from the land out to sea). It arises at sunset when the sea surface is warmer than the adjacent land due to the land having a lower heat capacity and cooling off faster. It then continues into the early morning hours until the heating of the day begins.

Land breezes are the opposite of sea breezes, which are gentle winds that develop over the ocean and blow onshore, keeping you cool during a scorching hot day at the beach. Although commonly associated with ocean shorelines, land breezes can also be experienced near lakes and other large bodies of water.

An Overnight and Early Morning Wind

Like all winds, land breezes form because of a difference in temperature and air pressure.

Land breezes come from different surfaces' abilities to retain heat. During the day, the sun heats land surfaces, but only to a depth of a few inches. When night comes around, the temperature of the land drops quickly because the surface no longer receives insolation from the sun, and heat is rapidly re-radiated back to the surrounding air.

Meanwhile, water retains more of its heat than land surfaces because of its higher heat capacity. The water along the shore becomes warmer than the coastal land, creating a net movement of air from the land surfaces toward the ocean.

Why? The movement of the wind is a result of differences in air pressure over the land and the ocean (warm air is less dense and rises, while cool air is denser and sinks). As the temperature of the land surfaces cools, the warm air rises and creates a small area of high pressure near the land surface. Since winds blow from areas of high pressure to areas of low pressure, the net movement of air (wind) is from the shore to the sea.

Steps to Land Breeze Formation

Here's a step-by-step explanation of how land breezes are created:

1. Air temperatures decrease at night.
2. Rising air creates a thermal low at the ocean surface.
3. Cool air collects, forming a high-pressure zone above the surface of the ocean.
4. A low-pressure zone forms above the land surface from the rapid loss of heat.
5. A high-pressure zone forms as the cooler land cools the air immediately above the surface.
6. Winds aloft flow from the ocean to the land.
7. Winds at the surface flow from high to low pressure, creating a land breeze.

Longer Near Summer's End

As the summer wears on, the temperature of the sea slowly rises in comparison to the daily temperature fluctuations of the land. As a result, land breezes last longer.

Nighttime Thunderstorms

If there is sufficient moisture and instability in the atmosphere, land breezes can lead to overnight showers and thunderstorms just offshore. So while you might be tempted to take a nighttime beach walk, be sure to follow lightning safety guidelines to reduce your risk of a lightning strike. Watch your step as well, since storms can stir up and encourage jellyfish to wash ashore!