By Vincent Pica
Commodore, First District, Southern Region (D1SR)
United States Coast Guard Auxiliary

Pollsters tell us that the most popular topic of conversation is the weather – and why not? We’ve written a lot about weather and seamanship, and this is true in all seasons, it is the localized squall that is more likely to catch us off guard than a widely heralded storm. This column is about that.

The Squall

In 2000, the actor Jeff Bridges starred in the movie White Squall as Captain Christopher Sheldon, skipper of the good ship Albatross. His mission was to teach a group of high school boys the way of the sea and of life – and a white squall provided the medium. I thought the portrayal of the squall was actually very realistic…having been in one or two over the decades.

What causes these furious fists of wind and water to appear, often on an otherwise lovely day? To start, a squall appears so well formed since it is essentially a block of wet, cold air that has dropped down from higher altitudes like an aeronautical rock. A warm upwelling of moist air rises into the colder altitudes and mixes with the cold upper air and immediately tips over and comes back to Earth – at speed. This can happen any time of the day but tends to accelerate in the evenings when temperature gradients can be the greatest. As the downdraft hits the surface, it spreads out like a spilt glass of milk hitting the kitchen floor. But while the milk has the possibility of spreading out equally in all directions, not so with our aeronautical rock. The squall will mix with the surface winds and will also be affected by the rotation of the Earth itself.

In the northern latitudes, unless there are strong surface winds at play, the squall will have a right shift – and the wind in front of it will be the strongest. In fact, this tends to create more squalls as the leading edge of the cold air forces more warm, moist surface air upwards – like a rock dropped in the water will cause a splash upwards and outwards. This effect creates “cells” of squalls that can roll in sequentially. When you feel the wind pick up and the temperature drop, this is the leading edge of a squall and, if one just went through, this one could be worse as the winds between the leading edge of a new squall and the trailing edge of the older squall can really get compacted – and hence more powerful.

What to do?

A squall’s strength, size and direction determine in large part what you can do. They tend to travel around 15 knots and are dark and brooding, even at a distance. I’ve seen squalls show up so solidly on radar that I thought we were approaching an uncharted island! How do you judge their power at a distance and formulate a plan? First, if you see lightning, it’s a strong one. Secondly, the taller the cloud, the more powerful the squall. If you’re out at night and you start to see the stars go out towards the horizon and the process continues towards you, batten down the hatches.

As they get closer, you can start to judge the strength by the rain image below them. If the rain (looks like gray or black “cotton candy” hanging from the cloud) is falling straight down or just slightly articulated, no or low winds. It’s just a gentle rainstorm. If the lines are at a sharp angle, tie everything down. Sometimes the area under looks “smoky” and that means lots of rain and wind. Anything else tends not to be much of an issue. There’s an old sailing bromide: “When rain comes before the wind, halyards, sheets and braces mind, but when wind comes before the rain, soon you make sail again.” If the wind comes before the rain, the rain is marking the end of the squall. But if rain comes first, it’s being pushed from astern…

Sailors have one option that powerboaters often do not. They don’t have to worry about running out of fuel, and can head out to sea and try to get behind the squall which definitely wants to run northerly and easterly (what we call a “sou’wester” since “winds are known from whence they blow, currents are known by where they flow”). With fuel a consideration, you might not feel it prudent to head further out to sea. Things to consider then:

1. Can you run before the squall without a fear of “pitchpoling”(being driven down the face of a wave by the storm and “going over the handlebars” when the bow plows into the bottom of the trough)?

2. Is there enough anchor rode aboard relative to the depth of the surrounding waters so you can drop the anchor and essentially heave to?

3. Are you close enough to port to put in?

Option 3 is obviously preferred. And, lastly, don’t be bashful about using your radio. The U.S. Coast Guard is Semper Paratus – always ready! ■

If you are interested in being part of the USCG Forces, email me at Vincent.Pica@cgauxnet.us or go direct to the D1SR Human Resources department, who are in charge of new members matters, at d1south.org/StaffPages/DSO-HR.php and we will help you “get in this thing.”

Captain Kevin Reed is the Captain of the Port and Sector Commander for U.S. Coast Guard Sector Long Island Sound. CAPT Reed is responsible for all active-duty, reservist and auxiliary Coast Guard personnel within the Sector. As a Commodore of the U.S. Coast Guard Auxiliary First District, Southern Region, Vin Pica works closely with CAPT Reed and his staff to promote boating safety in the waters between Connecticut, Long Island and 200 nautical miles offshore. Sector Long Island Sound Command Center can be reached 24 hours a day at 203-468-4401.