The Northern Caribbean Set to Experience its Worst Swell Event for the Season

Dale C. S. Destin |

Strong winds from a low-pressure system, some distance away, are pushing relatively large swells toward the northern Caribbean and the Bahamas, including Antigua and Barbuda and the rest of the Leeward Islands. Swells have started to arrive and will reach warning levels tonight through much of Saturday night.

NOAA Station 41044 – NE ST MARTIN – 330 NM NE St Martin Is showing relatively tall swells heading toward the northern Caribbean

This will be no Swellmageddon but it will be the worst swell event of the swell season: December to April. This event will see swell waves coming from the north-northeast at 2 to 3 metres (7 to 10 ft). Occasionally, they will reach 4 metres (near 13 ft). Though it will be no Swellmageddon, it will not be your garden variety swell event, as surf warnings are required.

Video by Windy.com showing swell heights

The possibility of significant wave heights (SWH) equaling or exceeding 3 metres or 10 feet. This is likely to expected in the northern coastal waters, according to the ECMWF IFS Model.

These swells will be virtually harmless in open waters, but they will be a very different “kettle of fish” when they run up on reefs and exposed northern and eastern coastlines which are relatively shallow and gentle to moderately sloping. In these environs, surfs (breaking swells) could be as much as twice the height of swells, as they crash onto shorelines.

Surfs at Fort James during a past swell/surf event

Such high swells and surfs will produce a high threat to life and property in the surf zone. There is the potential for extensive impacts. High surfs will result in beach closures, as swimming conditions will be extremely dangerous for beachgoers. Not entering the waters of affected areas would be a great safety idea and best advice.

The event will likely cause major beach erosion; possibly flooding of low-lying coastal roads; disruptions to marine recreation and businesses; financial losses and damage to coral reefs.

Although relatively small, this swell episode may also cause disruptions to potable water from desalination, as turbulent seas, will increase the turbidity of the water above tolerable levels for the desalting plants.

A high surf warning has been issued by the Met Office for Antigua and much of the rest of the northeast Caribbean. Other offices, as far west as the Bahamas, are expected to issue requisite marine alerts, if they have not done so already.

Precautionary actions: No one should enter the waters of the main warning areas: northern and eastern coastlines. All are also urged to stay away from rocky and or coastal structures along affected coastlines.

The impact on shorelines will not be the same everywhere. Depending on the depth, size, shape and the natural shelter of the coastal waters, the impact will be different. Shallow north-facing shorelines are expected to see the highest swells and surfs.

Seas are to return to safe levels by Monday morning.

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