Professional mariners heed the old adage “Mackerel scales and mares’ tails cause tall ships to fly low sails” and keep a weather eye to clouds portending incoming storms.
In most instances, recreational boaters can avoid boating in bad weather by checking the marine forecast and postponing cruises until the weather improves.
But once you’re on the water, a sudden severe thunderstorm can appear out of nowhere. That’s when seamanship—your ability to pilot a vessel effectively under adverse conditions—comes into play.
Seamanship involves a broad understanding of your vessel, how it handles in different situations and how it reacts under varying loads. Usually acquired over time, seamanship also requires knowledge of wind, water and geography, information you gain in the classroom and on the water.
You and your boat need to be prepared at all times. Keep anchors, rodes, life jackets and other safety equipment at the ready.
In a sudden storm, your immediate problems are limited visibility, high winds and, depending on your location, rapidly building seas. Remain calm. Have everyone dress warmly, put on life jackets and go below if possible.
Close hatches, doors, watertight compartments and windows to reduce the amount of water taken on board. In an open boat, passengers should sit low in the bottom of the boat along the centerline.
Although you should get your boat to the dock as quickly as possible, once waves reach a certain height, safety dictates that you match the vessel’s speed to the speed of the waves. That means slowing down a lot.
The more you reduce speed, the more you will reduce the strain on the hull and superstructure as well as the risk of portholes and windows popping out or breaking.
Keep your vessel at a 45-degree angle to the wind and make slow but steady progress to the nearest port, staying away from rocky shorelines. If you’re far from port, islands and peninsulas may offer shelter depending on the water depth and shoreline conditions. Keep in mind that the wind direction will probably change.
In a thunderstorm, winds generally blow outward from the area of heaviest rain. As the storm approaches, winds come straight at you. As it passes overhead, winds ease off and reverse direction. Understanding this pattern allows you to estimate how long you’ll be fighting the storm.
In smaller boats, putting up on a sandy beach may be a good idea. If the situation is life threatening, it’s better to sacrifice the boat to save yourself and your passengers.
To learn more about seamanship and boating in adverse conditions, take the USPS Seamanship course at a squadron near you.