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7x03 analysis part 2 — Too many Cats

Tommy flew a helicopter into a Category 5 hurricane, at least the show told us so. Is it even possible for an aircraft to fly in those conditions? Today, we are going to figure out just how strong the storm actually is canonically, and how realistic our beloved weewoo show is.

TW: Hurricane, extreme weather, natural disaster

What is the difference between a tropical storm and a hurricane? What even is a hurricane?

Both tropical storm and hurricane are tropical cyclones, just of different strength. A tropical cyclone is a rotating storm system with a low pressure center. The center, or the eye of the storm, sucks in warm moist air from an oceanic environment and it feeds into the generation of storm clouds that organize themselves into a spiral pattern due to the Earth's rotation, aka Coriolis effect.

A tropical cyclone is classified by its maximum sustained wind.

So if it's below 62 km/h, it's a tropical Depression. if it's between 63-118 km/h, it's a Tropical Storm. A Category 5 hurricane though has a maximum sustained wind speed of over 252 km/h.

A strong enough tropical cyclone is called a hurricane in North America, a typhoon in East Asian, and a cyclone in the Indian Ocean (including Australia).

How strong is the storm in 7x03 actually?

We first see the storm at the end of 7x01, when First Mate Kenneth tells Captain Ochoa there is a strengthening tropical storm in the ship's path. Captain Ochoa decides to reverse course back to LA and instructs Kenneth to alert the Coast Guard, but they get interrupted by the cartel.

Fast forward to 7x02, the next mention of the storm comes from Karen. When Hen is sent home by Chief Simpson, she tries to call Athena, but it goes straight to voicemail. Karen tells her cell service is probably spotty out at sea because of the hurricane, which has just got upgraded.

It's recently upgraded to a Category 2 hurricane, as we can see from Karen's tablet.

Then Hen goes to Maddie to ask the Coast Guard to look for Bathena's cruise ship. When Hen shows Maddie the ship tracking app on her phone, the time is 10:28. (I'm guessing PM because it's already dark outside during the Kyle Ortiz call.)

By the time Chief Simpson comes by to reinstate Hen, she's already talking about a Cat 5 hurricane. That can't be more than an hour or two later.

So which one is it? Is it a Cat 2 or a Cat 5? Who should I trust?

Tommy. Whenever he flies, his safety depends on his understanding of the local wind condition and weather. You should listen to him:

So it's a Cat 5, at least by the time the 118 set off on their journey to save Bathena.

Can a tropical storm intensify into a Cat 5 hurricane in hours?

No, not in real life. The record for most rapid intensification of a tropical cyclone is Hurricane Patricia in 2015, but it still took 24 hours. This doesn't mean the storm in 7x03 is completely made up. I believe I might have found the real life inspiration behind it.

Hurricane Otis (2023)

An area of low pressure formed on October 15, 2023 over the Pacific Ocean off the coast of Mexico. While it was during a significant El Niño period and the ocean temperature was record-breaking-ly high, strong vertical wind shear condition near the storm was predicted to hinder its development. It was originally forecasted to make landfall as a mere tropical storm. People in Acapulco went to bed on October 23 expecting moderate wind and light rainfall, many stopped seeking out updates of the storm.

In the early hours of October 24, meteorologists at the NHC recognized from satellite images that tropical storm Otis was rapidly intensifying into a hurricane. The NHC officially upgraded the storm to a Cat 1 hurricane at 13:00 CDT and sent out a hurricane hunter aircraft to accurately measure the actual wind speed of the cyclone.

Satellite images provide a pretty good model to estimate the strength of a tropical cyclone, but the most reliable way to measure wind speed is still to fly an aircraft into it and physically measure it. When the hurricane hunter managed to fly into the eyewall of Otis, everyone realized they made a huge mistake: Otis had already become a Cat 3 hurricane, and it was expected to strengthen even more. It takes time to process data received from the hurricane hunter, so operationally the NHC still classified Otis as a Cat 1 hurricane until the next advisory was scheduled to come out, which was at 16:00 CDT, but by that time, Otis was already near Cat 4 strength. It was then officially upgraded to a Cat 5 hurricane at 22:00 CDT.

While Otis did take around 24 hours to intensify from a tropical storm to a catastrophic hurricane, if you just look at the NHC advisories, it pretty much jumped from a Cat 1 into a Cat 5 in 9 hours. It caused extensive damage to Acapulco when it made landfall because the city was severely underprepared. I suspect the cruise ship disaster arc was inspired by hurricane Otis because it happened just a month after the writer strike ended. Also, in 7x02 Maddie, a 911 dispatcher, was not aware that the tropical storm had already strengthened into a hurricane, which mirrors the unexpected development of hurricane Otis.

As the storm in universe was going back at sea and not making landfall, the authority was probably in even less of a hurry to find out what the actual strength of the cyclone was. So it could take them even longer to send in weather reconnaissance aircrafts. I can imagine the 911-verse version of the storm jumping from a Cat 2 to a Cat 5 officially in mere hours.

Can a helicopter fly in a Cat 5 hurricane?

Technically yes, but the chopper won't be doing the flying. The aforementioned NOAA Hurricane Hunter is a Lockheed P-3 Orion specifically modified and fortified for weather information collection. If this four-engined workhorse has to fight tooth and nail against crosswind and turbulence in order to fly into the eye of the storm, a small single engine helicopter definitely would not fair any better. It would end up getting tossed around, a particular strong downdraft might slam it into the ocean, or a prolong bout of severe turbulence might rip it apart. Luckily in 7x03, Tommy is not actually flying into a hurricane, he's trailing behind it.

NOAA Lockheed WP-3D Orion Hurricane Hunter

In a blink-and-you-miss-it exchange between Buck and Tommy, after Tommy says "a Cat 5 hurricane passed through here", Buck asks why he means by "passed through" and what they are flying in at the moment.

"iNTermITteNt sHOweRs"

When looking at the cross section of a tropical cyclone, you can see rows of rainbands around the eyewall, increasing in size the closer it is to the center of the storm. If you have ever experienced a tropical cyclone making landfall, you would know it starts with sporadic bouts of rainfall (aka intermittent showers), which then gradually increase in frequency and severity as the storm approaches. Once you are within 100-200 km of the eye, wind speed would become violent while the rainbands become so wide and close together it basically keeps raining until you are right under the eye.

These are radar images of hurricane Irma (2017) making landfall in Florida. Bands of moderate to heavy rainfall spread across the inner core region of the cyclone, with still pretty consistent light to moderate precipitation between the gaps. But in the area further away from the eye in the southwest and southeast quadrants, you can see more squall line like patterns. Precipitation would abruptly begin and stop as you fly in and out of those outer lumps of clouds.

Wind speed in that area is no where near hurricane level even for a Cat 5 cyclone, it is typically under 100 km/h. That does not mean it is a safe condition to fly in. Because the outer rainbands of a cyclone are less affected by the storm's vortex dynamics, they behave more like regular thunderstorms. As you know, thunderstorms are big no-no's for aviation safety. In fact, the outer rainbands of a typhoon once contributed to a plane crash in Taiwan.

Conclusion

The hurricane in 7x03 is likely based on reality, albeit with a bit of exaggeration and a shortened timeline for dramatic effect. It is possible to fly and control a helicopter in this specific condition, but the danger is still quite high. Flying into a thunderstorm has a whole different set of risks associated with it, which I will tell you all about next time. Yes, part 3 of this series is "how to crash a helicopter with weather", so stay tuned.