Royal Caribbean is the only cruise line with dedicated meteorologists on staff, and that's a major asset during hurricane season.
With experts predicting an above-average season, Royal Caribbean Group Chief Meteorologist Craig Setzer works daily to keep cruise ships safe from any nasty weather.
Cruising during hurricane season always comes with the possibility that a storm could impact your vacation.
Mark Sudduth of Hurricane Track interviewed Mr. Setzer on an educational YouTube series called Hurricane U.
Setzer has worked for Royal Caribbean for the past 10 months and has now hired a second meteorologist to assist with weather monitoring.
With his expert knowledge, he's able to track weather events and notify captains if their itinerary needs to change.
Monitoring the weather
Craig Setzer describes weather monitoring as "slow-motion chess."
"You're anticipating, where's the storm going to be? Where's my ship going to be? What am I going to do with my ship?"
If a tropical storm or hurricane ends up moving across multiple itineraries, it becomes challenging, Setzer said.
Experts have to plan to move ships out of the way, and to different ports. Sometimes, the safer ports and destinations end up crowded with vessels as everyone tries to evacuate.
Setzer stays ahead of the curve during hurricane season, looking at the ensemble models every morning.
"You want to get [tropical storms] from the beginning," he said.
Ensemble models use numerical predictions to create a set of forecasts, providing a range of different weather outcomes.
In the cruise industry, Setzer looks at two different types of weather: port weather and voyage weather.
Port weather would affect ships when entering, exiting, or even staying in a port.
And voyage weather predicts where the itinerary needs to go, such as if the wind is too strong for the ship to get into a port, or if they'll need to avoid a tropical cyclone.
There's also a third type of weather event that Setzer has to deal with. He calls them unforeseen weather events.
"Unforeseen weather events"
Craig Setzer said that the biggest concern he deals with in the cruise industry are unforeseen weather events.
These are weather events that aren't well-modeled, especially out in the ocean where there's no radar coverage.
These events can be a microburst of air or a gust front of wind that wasn't visible on the forecast.
Setzer experienced one such incident just a month into his time with Royal Caribbean.
He said he was speaking to a particular captain and trying to get the ship quickly ahead of a high wind front up to 40 knots that was coming through.
Just an hour later, the captain called to show Setzer that the ship was experiencing winds of 65 knots.
"And I'm like, what is happening?" Setzer quoted. "It's ahead of what the forecast was. It's not even near what the forecast was, and it's higher than what the forecast was."
At the time, Setzer thought his job was over and joked, "Well, that was a short stint as a meteorologist for a cruise line."
Thankfully, the captain steered through the wind and the team later determined that it was a gust front that hadn't shown up in the models.
These unforeseen weather events "can also be the most disconcerting," Setzer said because if a big wind hits the ship, the vessel can begin to lean and cause the pools to spill over.
Using AI to predict the weather
As it turns out, AI marks a huge step in the history of weather modeling.
Previously in the maritime industry, "There's a sense of, oh, it was the weather, it happened, what could we do?" Setzer said.
But working at Royal Caribbean, Setzer intends to change that way of thinking.
"Not that [weather] just happens to us, that we can predict it, that we can avoid it, that we can take advantage of it."
He believes that AI can be used for this purpose, helping to learn the biases to adjust and fine-tune weather models.
"I see AI as right on the precipice of a big jump forward in terms of numerical modeling."
How cruise ships remain stable
How do cruise ships remain stable on the ocean?
Interviewer Mark Sudduth compared movement on the ocean to turbulence in the air.
"When it comes down to it, turbulence is not welcome in the ocean either," Sudduth said.
There are two types of motion on the sea, Setzer explained.
The first is synchronous roll, when waves hit the vessel from the side, causing it to rock back and forth.
The second is parametric roll, in which the frequency of the waves causes the ship to bob up and down and perform a rolling motion.
Both of these types of motion can be dangerous, so cruise ships use stabilizers to dampen and avoid it.
Stabilizers are "wing-shaped blades that stick out under the water on the ship. They will turn at an angle to counter the roll."
No matter the type of roll the ship tries to perform, the stabilizers go in the opposite direction to make sure the ship doesn't lean.
"It's amazing," Setzer said, and it's what works to keep everything on the cruise ship balanced, down to the straight pool tables.
When is the best time to cruise?
Cruising during hurricane season does come with a risk that a tropical storm could disrupt your itinerary.
However, Setzer doesn't discourage cruisers from sailing during hurricane season.
His role at the company exemplifies how Royal Caribbean seeks to keep its passengers safe and informed.
The ships reposition based on good weather for the region.
Plus: "You're not going to be impacted [by a hurricane] on a cruise ship because we're getting away quickly," Setzer said.
"The one thing that might happen is your itinerary might change."
Royal Caribbean's fleet doesn't play it close when it comes to hurricanes. Its ships can and do steer clear, far away from any storms.
Setzer just wants cruisers to remember to be flexible.
Do cruise ships get hit by lightning?
Lightning is another weather phenomenon that cruise ship captains have to be aware of.
When it comes to hurricane season, some tropical storms can also put out lightning.
"That is an issue," Setzer admitted, "our ships do sometimes get hit."
However, to avoid any damage or fires, Royal Caribbean vessels have a good grounding system, with lightning arresters and other tools that redirect the path of lightning.
Much like airplanes, cruise ships can be hit by lightning but have devices that channel the strike.
Thanks to these precautions, usually no damage is done.
The biggest risk with waterspouts
What about waterspouts? Are they a concern for cruise ships?
A waterspout is a spinning column or funnel of air and mist that occurs over a body of water.
Although waterspouts are usually weak, they have the potential to be almost as dangerous as tornados on land.
Craig Setzer said that waterspouts usually last a short duration.
The biggest concern during one is "the deck chairs on the upper decks blowing around."
If they get caught up in the wind of a waterspout, they could create a hazard.
"It's not the wind, it's the debris in the wind that could cause problems."
Because of this, if the bridge crew sees a waterspout approaching, they inform security and pool staff to evacuate the upper decks and close the pool.
Everyone should stay indoors until the ship passes the waterspout or the event ends.
What can people do to stress less about the weather on a cruise?
Should you be worried about the weather on a cruise?
Setzer believes that it's natural for travelers to feel a little apprehensive during hurricane season.
"It's just human nature that you're going to feel some stress. So accept the fact that you're going to be a little bit anxious."
However, passengers don't have to feel stressed about upcoming weather events.
"I'm watching the weather so you don't have to worry about it," Setzer likes to say.
"If there's something big, we're going to talk about it and we're going to let our guests know."
During his interview, he stressed that Royal Caribbean works to be transparent and keep guests as updated as possible.
"We tell guests everything that we know. And if we don't know what's happening, we'll say, we're monitoring the situation."
The cruise line always gives hurricanes a wide berth and updates guests if itineraries change as a result.
Read more: Safe at sea: what it’s like on a cruise ship when there’s a hurricane
Setzer said Royal Caribbean will inform guests ahead of time if ports change.
"If we have multiple port misses, then we start doing, refunds and credits," he added.
He recommends that guests don't feel anxious, but prepare to be flexible if they end up going to different ports.
"You may end up going someplace a little different, but I promise it's still going to be a good time."