this post was submitted on 05 Oct 2024
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[–] [email protected] 189 points 1 month ago* (last edited 1 month ago) (2 children)

Helene’s size shocked me but the storm surge for Katrina was unusually extreme. It was a well organized Category 5 and then weakened to a strong 3 right before landfall. 

To compare with Helene, which was similar in terms of (east to west) diameter but covered much more area overall, with category 4 winds at landfall: the Weather Channel was making a big deal out of the 8ft storm surges. During Katrina, the Mississippi Gulf Coast had a 28 foot storm surge. (The Miss. Gulf Coast isn’t that geographically different from the Fla. big bend region but that plays a role too.)

Helene’s unusual movement speed kept it strong very far inland and caused massive issues in places that rarely see tropical weather. Harvey was the opposite: it stalled over Houston and dumped days of rain on a major metropolis.

I wish we could update the Saffir Simpson scale to something that takes into account more variables. There are other measurements but no storm is identical in terms of damage potential. A category 5 can not even make landfall whereas something like Hurricane Sandy was a category 1 (or equivalent since it wasn’t technically still a hurricane) when it hit NYC and caused massive damage and flooded subway systems. Sometimes, a storm hitting a place that isn’t used to them can knock over all the trees or flood rivers while a similar storm would be nothing to Miami or New Orleans.

[–] [email protected] 67 points 1 month ago (1 children)

What surprised me most about Helene was the ground speed. I don't remember seeing any hurricane make landfall in the US moving at over 20mph. As a casual observer I have anyways seen 12 mph as a quick storm and 6 mph as slow.

[–] [email protected] 34 points 1 month ago

Yeah, I’ve lived in New Orleans or on the East Coast my whole life and don’t recall that sort of movement speed. Usually, you want a fast moving storm so no one area takes on all the rain but Helene was going so fast and was so massive that it’s probably unprecedented.

[–] [email protected] 30 points 1 month ago (4 children)

Helene is more deadly than Katrina if you don't count the deaths after the boat broke the levee that was well beyond its lifespan in New Orleans, which you shouldn't since that was a 100% fixable issue that was not taken care of.

[–] [email protected] 66 points 1 month ago (4 children)

We always say Katrina was a man-made disaster. I worry with climate change, that other places will be testing their infrastructure. Katrina should have been the canary in the coal mine and a lot of people just said, “Don’t live below sea level.” Old river damns can break just as easily as neglected levees.

[–] [email protected] 37 points 1 month ago (1 children)

It was definitely a man-made disaster when it came to New Orleans. I made this analogy to someone else: if lightning strikes a skyscraper and the skyscraper burns down and kills everyone inside due to a lack of a sprinkler system, is that really death by a natural cause? I would say it's death by gross incompetence.

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[–] [email protected] 165 points 1 month ago (2 children)

Good news! It's gonna get worse! Much, much worse! Say thank you to petrol states and companies, preferably by blowing up their infrastructure

[–] [email protected] 76 points 1 month ago (4 children)

And a big thank you to politicians blocking major efforts to reduce carbon emissions thanks to lobbying by the industry and foreign governments.

The world finally needs to stop politicans getting huge donations and hold them accountable for their actions.

[–] [email protected] 36 points 1 month ago

And also acting like "climate change" is a taboo topic that should never be spoken over the air, lest you offend someone.

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[–] [email protected] 84 points 1 month ago (2 children)

Are these pictures even on the same zoom level?

[–] [email protected] 136 points 1 month ago (2 children)

You are correct, they don't appear to be. This one seems more accurate there, but the difference is still stark:

[–] [email protected] 52 points 1 month ago

I was going to correct you on the comparison and I tried making my own scaled image .... but I couldn't because yours is a correct scale

I just couldn't believe that Helene was that massive and widespread compared to Katrina which was known as a major event. wow

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[–] [email protected] 43 points 1 month ago (4 children)

They are not, but I think the main focus is on how obscenely tall Helene was. There's many parts of the US that weren't prepared because they didn't think it would reach them

[–] [email protected] 41 points 1 month ago (1 children)

There were warnings for Georgia and the southern Appalachia, but the storm moved so much faster at the end and carried so much water inland. The ability to hold more water in the atmosphere has been an ongoing concern from climate scientists, and this is a clear example of how it can lead to disaster.

[–] [email protected] 23 points 1 month ago

This bundled with droughts that cause the ground to not be able to absorb the water, causing serious flash floods, is just a start. I'm guessing in the next ten years, we'll see this happening more and more each year for inland areas

[–] [email protected] 20 points 1 month ago (1 children)

We even got some excessive wind in Chicagoland, which was obviously from the hurricane, because it was coming from the east. Normally, the wind here comes from the west.

[–] [email protected] 15 points 1 month ago (6 children)

Reminds me of youtuber LGR's latest video, he didn't prepare much because the storms don't normally reach that far inland, and unfortunately he had a lot of his collection damaged because 2 massive trees sliced his house clean in half. Makes me think that the midwest will soon get more populated due to its position away from coastlines

[–] [email protected] 20 points 1 month ago (6 children)

Makes me think that the midwest will soon get more populated due to its position away from coastlines

We have our own shit show of extreme weather. For example, derechos (an oceanless, inland hurricane essentially) used to be rare. We've had 2 massive ones in the last 4 years. This summer alone there were hundreds of tornados hitting places that rarely ever see them. Hell, it's god damn October and we're still having ~90°F days, which hardly ever used to happen.

[–] [email protected] 16 points 1 month ago (1 children)

In nebraska here under a Red Flag warning and a high of 91 today

EDIT : Correction, forecast updated with a high of 102... in fucking october. Holy shit

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[–] [email protected] 11 points 1 month ago (2 children)

If you are ever fortunate enough to pay off your house DO NOT go without insurance because you can

[–] [email protected] 13 points 1 month ago

Pretty much all home insurance doesn't cover hurricane related damages if you're on the east side of the US.

[–] [email protected] 13 points 1 month ago (1 children)

In some parts of Australia you cannot insure your home any longer due to climate change.

[–] [email protected] 12 points 1 month ago* (last edited 1 month ago) (2 children)

Florida and California are getting like that in the US. The lawyers and public adjusters are contributing to the problem by suing and shaking down every insurance company that stays in the state. In California they are begging them to stay…

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[–] [email protected] 12 points 1 month ago (1 children)

Wasn't a big part of Katrina's destruction from the hurricane effectively stalling over the southern US which caused prolonged and massive local damage?

Not trying to discount either event, mostly worried about the time we get a stalled Helene sized hurricane

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[–] [email protected] 76 points 1 month ago* (last edited 1 month ago) (1 children)

Well, it's not over.

This is coming next week. Path is unclear, and its not as big as Helene, but anything near a 930mb in Tampa Bay and plowing over Orlando at 950mb, especially at this angle, is a catastrophe.

Katrina was 920mb at landfall, and these intensity forecasts have been undershooting hurricanes recently.

And there's another low pressure system at the edge of the GFS that I don't like, taking a similar path to Helene:

This is what the upcoming hurricane looked like a few days ago.

[–] [email protected] 16 points 1 month ago (1 children)

It's clearly trying to help the US by amputating the injured limb.

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[–] [email protected] 61 points 1 month ago* (last edited 1 month ago) (10 children)

I remember when conservatives were hooting and hollering about Climate Science Being Wrong, because the predicted "Worst hurricane season on record" wasn't producing a record number of powerful storms.

Well... now what? I guess we can fall back to Gaetz and DeSantis blaming Biden for a bad cleanup job. Or go the MTG approach and start talking about HARP and the Jewish Space Lasers.

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[–] [email protected] 52 points 1 month ago (2 children)

As with everything, it also matters where it hits.

Katrina and New Orleans's levees was a big deal. Helene flooding areas many moles from the coast in high altitude areas.

There have been bigger hurricanes that do less damage and likely there will be future weaker ones that do more.

[–] [email protected] 22 points 1 month ago

I too worry about the poor moles getting flooded!!

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[–] [email protected] 50 points 1 month ago* (last edited 1 month ago) (4 children)

What I don't like about these graphics is there is no data source so you have to look it up to know how much to believe about what they say. So for those wondering, per Wikipedia:

  • Helene was a Cat 4, its max diameter was between 400-450 miles, max wind speed of 140 mph is correct. Known fatalities so far > 227 and counting.

  • Katrina was a Cat 5, 400 miles in diameter as shown, but with a max windspeed of 175 mph, not 125. For those too young to remember, Katrina was a very, very bad storm. So bad. Over 1392 fatalities (official estimate; exact number unknown). BTW Katrina also had a big tail/wing(?) stretching to the north when it hit land like what Helene had, but thinner since further west--but those don't count as part of the measured diameter of the hurricane.

My opinion of this graphic: Hurricanes are getting worse because of climate change, but we don't need to convince people of that by downplaying Katrina or making Helene look scarier--Helene is also very very bad. It's all bad, folks.

Katrina photo:

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[–] [email protected] 32 points 1 month ago (20 children)

Not sure what the science is between 2 images with no source or timestamp and nearly 20 years of technological improvement between them is but this isn't the peak of Katrina

Katrina ultimately reached its peak strength as a Category 5 hurricane on the Saffir–Simpson scale on August 28. Its maximum sustained winds reached 175 mph (280 km/h) and its pressure fell to 902 mbar (hPa; 26.63 inHg), ranking it among the strongest ever recorded in the Gulf of Mexico.

It probably refers to its stats at landfall

Katrina weakened to a Category 3 before making landfall along the northern Gulf Coast, first in southeast Louisiana (sustained winds: 125mph) and then made landfall once more along the Mississippi Gulf Coast (sustained winds: 120mph). Katrina finally weakened below hurricane intensity late on August 29th over east central Mississippi.

But power doesn't equal damage for weather

[Katrina] is the costliest hurricane to ever hit the United States, surpassing the record previously held by Hurricane Andrew from 1992. In addition, Katrina is one of the five deadliest hurricanes to ever strike the United States

Sources:

https://en.m.wikipedia.org/wiki/Meteorological_history_of_Hurricane_Katrina

https://www.weather.gov/mob/katrina

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[–] [email protected] 29 points 1 month ago

It’s also good to remember that Katrina’s storm surge and the subsequent failure of the levees and flooding of the city is what was so damaging.

Besides the wind and rain the destruction of the levees took a huge toll on New Orleans.

[–] [email protected] 22 points 1 month ago (1 children)
[–] [email protected] 23 points 1 month ago (6 children)
[–] [email protected] 30 points 1 month ago

It's a real screenshot from 2004's banger The Day After Tomorrow.

[–] [email protected] 19 points 1 month ago (3 children)

Hate how people are downvoting this guy just for asking a question, like what is this, reddit?

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[–] [email protected] 15 points 1 month ago* (last edited 1 month ago) (2 children)

Why would a satellite actually imaging storms want to place a satellite in the image as well?

I think its from some movie, like "the Day after Tomorrow" or something.

Because in movies you can have a shot of a satellite while showing a shot of the storm. I think that's fairly harder to do in real life, seeing you'd have to have two satellites perfectly in sync (and they go pretty fast) or a satellite (space stations are satellites as well) with a very long selfie stick.

Edit actually yah googled "the day after tomorrow storm" and this was one of the first images to pop up, the exact same image https://www.syfy.com/sites/syfy/files/styles/scale_862/public/2022/12/storm.jpg

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[–] [email protected] 18 points 1 month ago (4 children)

Wow, so according to MTG, I guess Democrat technology has really advanced over the past few years!

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[–] [email protected] 15 points 1 month ago

As someone not from hurricane continent, these images are freaking scary. Like what do you mean the hurricanes are several times bigger than my entire country?

I'm just sitting here thinking holy hell I hope cyclones don't come to my comfy corner of North-Eastern Europe

[–] [email protected] 12 points 1 month ago (1 children)

With Climate Change we'll eventually run out of names. Unless Hurricane Karen manages to be the one that kills everyone before that happens.

[–] [email protected] 15 points 1 month ago (2 children)

There are something like ~500 million names.

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[–] [email protected] 12 points 1 month ago

Wimdy.

But the least wimdy going forward.
We gonna achieve such terrifying new records in just years!

[–] [email protected] 10 points 1 month ago (1 children)

Helene looks like a thrice-divorced hurricane.

I think we’re just a few years away from the planetary cyclones in Day After Tomorrow.

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