Thinking about Florida right now and any of you Florida GTers - I know you know what to do. Go get your brown liquor (that’s not just Louisiana is it?).It’s also the Katrina anniversary. When [not really a] Hurricane Barry came to Louisiana a month or so ago, I posted some info about hurricane literacy for those of you who don’t really know how to watch a hurricane or what it’s like. I thought it might be relevant if you or someone you care about is in the path of Dorian. I’ll quote some of the relevant stuff from that post, which was really detailed, but the TL;DR is basically:
- Category = wind but doesn’t account for rain. Some of the worst hurricanes in history have been low category because they were rain monsters. Don’t fixate on the category - it’s only part of the equation.
- Pay attention to local news from the affected areas and fuck the national news - they’re there to entertain outsiders, not inform anyone.
- It’s really, really difficult to know exactly where a hurricane will be the most severe until it’s too late to do anything about it. This means there are giant swaths of people who get over-panicked and over-prepared each time, because frankly they’re all at risk until they’re not. That’s why you often see hurricanes hyped up but then the devastation is limited.
Understanding hurricane severity
Tropical storms and hurricanes are pretty much defined in the media by their wind speed. Hurricane categories are all wind speed but doesn’t take anything else into account. Storms have their own characteristics - they are special snowflakes. Some are a wind threat (which also brings a lot more storm surge flood threats, but whether those apply to you directly depends on your topography). Some hurricanes are more characterized by rain, bringing other types of flood threats. The way these threats manifest depends on a ton of tiny details.
So categories are not a complete picture of severity. Harvey, which fucked over Houston last year, was a Cat 1 but it sat on top of the city and just dumped rain on them forever. Florence was similar. You have to look to local media and really the NOAA to find accurate information on what to expect from a hurricane.
When a hurricane hits land, it immediately starts to weaken in terms of wind speed, but not rain. A rainy hurricane can do more serious damage further inland than a windy one.
Why are hurricanes so unpredictable?
They move slowly but spin. So the little details of who’s going to get rain exactly when are almost impossible to know. Other things affect the threats - including the topography and waterways, the angle at which it makes landfall, and forward speed at landfall, and so the exact same hurricane can have very different effects even if it moves just a few miles east or west. How fast a hurricane moves also affects these things - whether it moves at 2 or 12 mph might be the difference between life or death (faster is better).
Whether you are in New Orleans or a little over an hour away in Baton Rouge, you PROBABLY don’t know which of the two of us gets fucked worse until the 11th hour.
The picture in your mind of a hurricane - spirally clouds with an eye - means the storm is “organized”- once it organizes, the predictions become much more accurate but at the same time, that’s often very close to landfall and sometimes too late if you want to evacuate. That’s why you see a lot of evacuations called prematurely that weren’t needed - because they don’t want to err in the other direction. Barry...uhh, look at this fucking shit. He hasn’t organized at all so the meteorologists have been like UMMMM with this one. It’s been part of the anxiety and confusion.
What is being in a hurricane like?
Mostly just waiting around. The safest thing to do is stay the fuck put. Sometimes it’ll deluge and the wind will go nuts and then it’ll be calm for six hours and then start up again. You often can’t tell what part of a hurricane you’re experiencing unless you look at a radar. Hurricane Isaac in 2011 sat on top of us forever but was all wind, so it just sounded like a white noise machine for 2 whole days.
The part you need to be most worried for is afterward when you are out of power. Isaac was super chill but blew wind for so long power lines were just down EVERYWHERE. It took some people 2-3 weeks to get power back and that shit barely affected anyone around here otherwise. With notable exceptions, the most people who died in Katrina died in the aftermath - of disease from the toxic flood waters, of not being able to find food or water or medication, of sun exposure and heat exhaustion, etc. That is the biggest threat no matter what, and often is the reason people evacuate even if it seems like an overreaction - for whatever reason, they or their families will be vulnerable without power.
Sending love to everyone this hurricane season.