Surf forecast glossary: 31 surf terms explained

A-frame

A peak that breaks both left and right, so two surfers can ride it in opposite directions. Beach, point and reef breaks

Barrel

The hollow part of a wave where the lip throws out over the face. A surfer rides inside it. Also called the tube. Beach, point and reef breaks

Beach break

A wave that breaks over a sandbar. The sand moves with each storm, so the peaks move too. Beach, point and reef breaks

Buoy height

The height of the swell in deep water, measured by a buoy. It is the average of the biggest third of the waves. It is not the face height you ride. Buoy height vs wave face

Close-out

A wave that breaks along its full length at the same time. There is no shoulder to ride. Beach, point and reef breaks

Cross-shore wind

Wind that blows along the beach, between offshore and onshore. It makes the face a little bumpy. Offshore and onshore wind

El Niño

Warm water in the tropical Pacific every few years. It changes where winter storms go, and that tends to change which coasts get more swell. El Niño and surf

Face height

The height of a wave on its front as it breaks, from the trough to the lip. BarrelFare shows face height in feet. Buoy height vs wave face

Fetch

The length of open ocean that the wind blows over. A long fetch makes a bigger, longer-period swell. Wave period

Glassy

Very light wind, under about 4 knots. The water surface is smooth. Offshore and onshore wind

Groundswell

Swell from a strong storm far away, with a period of about 13 seconds or more. It has more power than wind swell of the same height. Wave period

Hollow

A wave with a steep face that throws its lip out. Reefs and shallow sandbars make hollow waves. Beach, point and reef breaks

Knot

The unit of wind speed in most surf forecasts. One knot is about 1.15 miles per hour. Offshore and onshore wind

Lineup

The area just past where the waves break, where surfers sit and wait.

Mushy

A slow, soft wave with little power. Onshore wind, high tide or a short period can make waves mushy. Tide and surf

Offshore wind

Wind that blows from the land to the sea. It holds the face up and makes the wave clean. Offshore and onshore wind

Onshore wind

Wind that blows from the sea to the land. It pushes the wave over early and makes the surface bumpy. Offshore and onshore wind

Overhead

A face height taller than the surfer. Double overhead is about twice the surfer's height. Buoy height vs wave face

Peak

The highest point of a wave, where it starts to break.

Period

The time in seconds between two waves passing one point. A longer period means more power and a bigger face for the same buoy height. Wave period

Point break

A wave that bends around a headland and peels along it in one direction. Point breaks give long rides. Beach, point and reef breaks

Reef break

A wave that breaks over rock or coral. The bottom does not move, so the wave breaks in the same place each time. Many reefs need mid or high tide. Beach, point and reef breaks

Score

BarrelFare's rating from 0 to 10 for each hour at a break. It compares the face height, swell direction, wind and tide to what that break likes.

Season

The months when a break gets its most good swell. Big swell follows winter storms, and winter is in different months on each side of the equator. Surf seasons

Set

A group of bigger waves that arrive together, with smaller waves between sets. Wave period

Swell shadow

A part of the coast that an island or headland blocks from a swell. A break in the shadow can be flat on a big day. Swell direction and the swell window

Shoulder

The part of the wave next to the breaking part that is not yet breaking. The surfer rides along it.

Swell direction

The compass direction the swell comes from. 270° is a swell from the west. Swell direction and the swell window

Swell window

The range of swell directions that can reach a break. The coast blocks the other directions. Swell direction and the swell window

Tide

The rise and fall of the sea level, about twice each day. It changes how deep the water is over the sand or reef. Tide and surf

Wind swell

Swell made by wind near the coast, with a period under about 9 seconds. It is weaker and less organized than groundswell. Wave period

How to read a surf report and forecast