Preparing Your Boat for the Hurricane Season

While the precise season varies slightly year to year, the Atlantic hurricane season generally spans June through November and the Pacific season generally begins a couple of weeks earlier.

Most of us who spend a lot of time around or on the water know that storm frequency and intensity have worsened in recent years, and research supports these observations.

“The intensity, frequency, and duration of North Atlantic hurricanes, as well as the frequency of the strongest hurricanes, have all increased since the early 1980s. Hurricane intensity and rainfall are projected to increase as the climate continues to warm.” – U.S. Global Change Research Program

The good news is that the individual factors that coalesce to create hurricanes are part of larger weather systems. While hurricanes often change paths (sometimes for the good, sometimes for the bad), they don’t pop up out of nowhere. While the exact intensity and level of damage is not highly predictable, their presence is. Preparation is not only possible, but critical.

This guide was designed to:

• Help you to better understanding the factors that cause damage to boats in hurricanes or intense tropical storms
• Assist you in thinking through the options for best securing your boat

The Factors that Cause Hurricane Damage

There are four primary factors that put your boat at risk during a hurricane or violent storm—wind, rain, waves, high water, and flying objects.

Wind

Hurricanes are well known for their wind speeds—70 to 130 mph are common. However, what is not as well understood is the force created by these winds. Wind speed that has doubled, quadruples wind pressure. So, as wind speeds increases, the damage inflicted increases at a much greater rate.

Takeaway: Reducing your boat’s windage is a critical action step when preparing for a hurricane. Remove as much rigging and canvas as possible. In short, remove everything you possibly can that is likely to be caught by the wind. Also, if possible, face the boat's bow toward the greatest wind exposure.

Waves

It is pretty easy to envision the scale and damage ocean waves can cause. However, even in smaller harbors, bays, and lakes, waves can build to astounding heights. Seawalls, barrier beaches, and other structures that are normally quite protective are often submerged by the storm surge.

Rainfall

Rainfall of six to 12 inches within 24 hours is normal during a hurricane. In recent history, there have been hurricanes that have delivered much greater quantities of rain. Even boats that withstand damage from wind, waves, surge, and airborne objects can be sunk by overwhelming volumes of rain. Cockpit decks are seldom 100% watertight, and too often bilge pumps can’t keep up. Additionally, deck drains and pump discharges located near the waterline can backflow when put underwater by rain and waves.

Surge

Heavy rainfall and waves are easily understood contributors to high water levels. But, surge results from a combination of factors and is often the largest contributor to extreme water level highs.

Due to low barometric pressure, the ocean surface is drawn upward forming a mound about one foot higher than the surrounding ocean. Large swells generated by the storm reach land first, while storm winds drive water toward the coast. As the storm makes landfall, water levels can dramatically surpass high tide water levels. Surge is often the largest culprit contributing to extensive flooding and much of the loss of life that accompanies a hurricane. Additionally, surge accounts for a lot of boat damage because it can put docks and associated dock lines underwater as the boat tries to float above.

Takeaway: For boats that remain in the water during a hurricane, positioning and length of dock lines are critical. You’ll want a highly secure, “spiderweb-like” configuration with you boat positioned in the center.

Airborne Objects

As discussed above, the force from high wind can cause tremendous damage. Additionally, there are typically a lot of things flying around during a hurricane. If your boat is not damaged directly from wind speeds and pressure, tree branches, pieces of buildings, and materials of all types are often flying about and can all too easily collide with your boat.

Create a Plan

You must plan how you are going to best protect your boat well before a storm is in the forecast. Of course, when a hurricane is predicted, you will be far from the only person in your area trying to secure your boat. Knowing exactly what you are going to do and acting quickly based on initial forecasts is critical. Don’t wait for the storm to become more certain as, depending on the type of boat you have and your plan, you might have a very tough time executing.

As you develop your plan for protecting your boat in a hurricane, you will need to:

1. If you have a slip at a harbor or marina, review your dock contract for language that may require you to take certain steps or to leave the marina when a hurricane threatens. Also, ask the marina manager about its hurricane plans.
2. Determine where your boat will best survive a storm and figure how what steps you will need to take when a storm is on the horizon.
3. Make sure you have needed products (like plenty of dock line, chafe guards, etc.) at the ready.

Options for Protecting Your Boat During a Hurricane

The plan to protect your boat during a hurricane will depend on a variety of factors such as the size of your boat, the size and resources of your harbor or marina, and the presence of nearby protected waterways. The most common options for protecting boats from storms include hauling them out of the water, securing them on the water, utilizing floating docks, trailering them to your home or other protected location, and utilizing protected waterways like nearby canals or rivers.

Hauling Boat Out of the Water

For many boat owners and marinas, hauling boats out of the water is the pillar of the hurricane plan. Forward thinking marinas have plans in place and pull as many boats out of the water as possible whenever a storm is approaching. They will then likely plan to secure the boats that cannot be hauled out in the largest of the slips remaining.

Some boats like smaller, open boats or high-performance powerboats with low freeboard will almost always be overcome by surge, waves, and rainfall and must be pulled out to protect them.

Fortunately, because they are smaller, most of these boats can be placed on trailers and transported to a safe location inland.

Securing Boat on the Water

Any boat in the water should be secured in a protected harbor. The question is deciding which harbors will still be safer and which will be vulnerable. Storm surge is a major consideration and rocks are another factor to think about. Rock-strewn harbors are pretty during normal times, but they are not good for housing your boat in a storm because if your boat breaks loose, a lot of damage can be caused by your boat being slammed against the rocks.

Look for harbors where you can anchor in sand, clay, hard mud, or soft mud. Also, use high quality dock line, think carefully about the best way to secure your boat to sturdy structures (sturdy trees, pilings, etc), and use chafe protectors to reduce intense friction on your dock lines that can lead to breakage. Done correctly, your boat should resemble a spider suspended in the center of a large web with dock lines protected at fiction points by chafe protectors. An effectively constructed web will allow the boat to rise with the surge and be bounced around by the storm, but avoid breaking loose and colliding with other boats, the shore, or other objects.

Floating Docks

Floating docks will rise with the surge allowing boats to be secured more easily than at fixed docks—the boat and the dock rise and fall together.

Because they rise with the surge, floating docks allow boats to be secured more readily than boats at fixed docks. However, the floating dock’s pilings must be tall enough to accommodate the surge. You must measure the pilings’ height to see whether than are taller than the predicted storm surge. If they are not taller than the surge, your boat and the floating dock will together be pushed above the pilings and wash to shore as a tangled unit.

Canals, Rivers, and Waterways

Canals, rivers, or other waterways can be effective shelters and might be better a better option than a crowded marina or harbor if you cannot pull your boat out of the water.

Just as with the fixed dock arrangement described above, you need to secure your boat in a spiderweb configuration—your boat securely tied to fixed objects and is the “spider” in the center of the web.

Your boat should be facing the canal’s entrance and be as far back from open water as possible.

Another option is mooring or anchoring (or both) in a suitable waterway. A boat on a mooring can swing to face the wind, which reduces windage, and it can’t be slammed into a dock unless the mooring or anchor drags.

However, the mooring must hold. Both mooring and anchoring with an anchor with suitable holding power is recommended.

Trailerable Boats

If your boat can be trailered, pull your boat out of the water and trailer it inland to a protected location. Make sure the location you decided upon will be far enough away from the predicted surge.

If you trailer your boat to you home, consider pulling your boat into you garage rather than you car. Your boat is lighter than your car or truck and is more susceptible to wind damage.

If you leave your boat outside on its trailer, further secure by letting some air out of the trailer tires and block the wheels. You can increase the weight of light boats by leaving in your drain plug and using a garden hose to add water.

Also, place wood blocks between the trailer’s frame and springs to support the increased weight. If you have a boat with a stern drive, remove the drain plug so that the engine won’t be damaged by flooding. Secure the trailer to trees or with anchors or augers. Remove all loose gear like bimini tops, canvas covers, and electronics and secure the boat to the trailer.

Storage Racks

A storage rack can be a good option if you trust the rack’s construction and the people operating it. The owner/operator of the rack should know how much wind the rack/steel building was designed to withstand. If there is any doubt about the rack’s structural integrity, take your boat elsewhere as storage racks have been known to collapse.

Final Tips for Protection Your Boat from Hurricanes

• Larger diameter dock lines should be used to resist chafe and excessive stretching. Generally, use 1/2” line for boats up to 25’, 5/8” line for boats 25’ to 34’, and 3/4” to 1” line for larger boats.
• Use chafe protectors on any portion of the line that will be asked to withstand substantial friction. Dock line can be weakened by chafing and break. Also, the forced caused by hurricane winds have been known to inflict so much friction that they can cause line to melt.
• Charge your batteries and make sure they can run automatic bilge pumps throughout the storm. Consider adding back-up batteries and shut off all other devices that consume electricity.
• Cockpits and boat structures are not watertight. So, use duct tape around hatches, ports, lockers, and other openings to prevent water accumulation in these areas. Experiment with different brands of duct table to determine which leaves less residue. Close all openings but the cockpit, drain seacocks, and insert a plug into the engine’s exhaust openings.

We hope this guide has helped you to begin making a plan to keep your boat as safe as possible during a hurricane. Shop PartsVu for anchors, dock line, and other supplies needed to help keep your boat safe and secure.