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Comment by acchow | Hacker News Reader

"The National Hurricane Center says cones will contain the path of the storm center only 60 to 70 percent of the time"

Sounds like the communications fix is easy. Increase the uncertainty to 90-95% which also increases the cone size. And make it blood red and tell anyone inside the red that they need to be prepared.

"Hurricanes are also hundreds of miles wide, and the cone shows only the possible path of the storm’s center"

Add an additional yellow area around it. This makes it extra clear visually that the red zone is quite bad.

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Right. Some of the "popular interpretations" dismissed in the article are correct, or wrong only in degree rather than in kind. Your home is more in danger inside the cone than out of it, and it is more in danger at the centre of the projected path than at the fringes of the cone.

If the problem is that people with a low to moderate risk of losing their home or their lives don't prepare enough, then yeah, show a wider area, or the two-level nuance of "red threat" and "yellow threat". And balance it against the inevitable "well, the last four times the government said there was a storm threat it didn't come near here, hell, the last time it made landfall 400 miles away".

But probably is not intensity. Half chance of full intensity doesn't mean full chance of half intensity. If you'd evacuate the red zone but not the yellow understand, do you really understand the bet you are making?

I've been living with hurricanes my entire life, and have been through many (the largest was Hugo in '89). The problem with all these cones is when they extend them beyond 72 hours. At that point, if we used your suggestion, the entire east coast could be in the cone. That means either no one pays attention, or everyone evacuates and next time ignores the warnings.

What officials (and the news) need to do is tell everyone to hold tight until 3 days out, and then start making decisions.

People also need to understand their personal situation. If an area floods during a summer rain storm or simply when the tide is high, then they need to be extra cautious.

The other problem is that many people simply have no idea what it's like to go through a hurricane. The mass migration to the coast means large parts of the population do not have the experience to make informed decisions. This goes back that officials and the news need to do a better job at informing.

My personal rule to consider evacuating is a cat 4+ predicted direct hit or just south and it is less than 48 hours out.

I feel like the news and government response has been to very strongly err on the side of caution lately. The moment the path was updated to move to a direct hit of north Florida yesterday, grocery stores and gas stations were flooded with people preparing a week in advance. 10 or 15 years ago you'd hear a lot of "well a storm hasn't hit here in 100 years" in the region, but nobody fucks around like that anymore.

Evacuation should be done relatively late/certain. Preparation should be done weeks to months in advance.

Frankly I wish stores would have random "everything costs 2x" days all the time to teach people the importance of stocking up on necessities.

> My personal rule to consider evacuating is a cat 4+

As you know well having lived through Hugo, the S/S category pertains to the wind speed. However, it's the flooding and storm surge, not the wind, that are by far the most deadly features of a hurricane.

I'd be much more wary of a big, slow moving cat 2 arriving right at high tide and full moon than I would be a small, fast moving cat 4 arriving at low tide and a new moon, unless I have some particular reason to fear the wind and not the water (eg I'm in a mobile home on high ground).

Source: lived through or evacuated for multiple hurricanes.

Note for the record that large tides (spring tides) are associated with full moon and new moon. Smaller tides (neap tides) are associated with half moons.

You're absolutely right. I've been living away from the coast for too long now (~15 years).

Absolutely agree on the flooding angle being the biggest danger. It's why I mentioned that people need to be aware of their personal situation.

You have to balance it with they crying wolf problem. If you make the cone too big, every hurricane will trigger a warning and then people will ignore it if the hurricane keeps missing them.

I think that would be a pretty big cone. You might end up with the situation where nobody takes it seriously - "oh I was in the last 5 cones this year and didn't get a single drop of rain" type of attitude.

> prepared

And tell them how to prepare.

Florida native and I've live here all my life. If you're within the radius of hurricane force winds, live near the coast, live in a flood prone area, live in a shed, live in a trailer, you should take these storms seriously. If you're inland, and not in a shed or trailer, you should be fine if you don't do something stupid, like stand outside. Don't go out and hurricanes are rarely more than a nuisance to those inland.

This is a compact storm; it's HFW extend out 15 miles. Anyone outside of that and not on the coast isn't going to have much to worry about.

> And tell them how to prepare.

Exactly. I made a comment above that mentioned the mass migration to the coasts means that many people do not have years of experience dealing with hurricanes. What you just said is common sense for you and I, but may be a complete unknown to someone who just moved from NJ or Ohio.

I moved to Florida from Sweden 1.5y ago. The most extreme weather preparations I've done in the past were putting the garden furniture in the garage so it wouldn't tip over.

Currently prepping for Dorian in Orlando :)

That won't fix the problem. The NHC uses an ocean model, but the transition across Florida requires the application of a hybrid land/water model, which results in a large divergence when the results of the different models are combined. Fortunately, someone from Mississippi State University developed such a model in 2004. It successfully predicted the exact path of Hurricane Katrina over a week in advance of landfall. That weather model is used for XM Sattelite Weather and the Gulf Coast Hurricane Index, but the NHC still hasn't adopted it after 15 years.

Something like this? https://www.nhc.noaa.gov/refresh/graphics_at5+shtml/025521.s...

I’ve only had to deal with one hurricane personally (Irma), and the forecast cone was only useful as an indicator to pay attention to the other, more detailed forecasts. As far as I’m concerned, it’s a relic from when weather forecasting models were much more primitive and graphics had to be reducible to B+W for printing.

To be fair, on all those forecast cone graphs, it says in bold font:

"The cone contains the probably path of the storm center but does not show the size of the storm. Hazardous conditions can occur outside of the code."

But I agree, the wind speed probability plot is much more useful. Like https://www.nhc.noaa.gov/refresh/graphics_at5+shtml/204603.s...

people are really bad at understanding probabilities. just look at people's interpretations of polling analysis before the 2016 election. or people's complaints of missing 95% shots in xcom.

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