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Comment by rbritton | Hacker News Reader

This site makes an appearance on HN somewhat regularly, but in case it's new to anyone, it tends to be a pretty useful forecast visual for wind: https://www.windy.com/?25.820,-67.720,5

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It's also interesting to look at the bigger picture. The southern hemisphere has its own level of insanity going on:

https://www.windy.com/?-22.513,39.375,3

I think that's somewhat normal below 40 degrees south. Lots of open ocean without any significant land masses to slow things down. See more here:

https://en.wikipedia.org/wiki/Roaring_Forties

lest we forget the Furious Fifties

Is that normal?

Yes. There's no land around 40-50°S, so you basically get in effect a permanent storm over ocean with nothing to break the wind. It's why the weather in Antarctica is so much severer than that in the Arctic.

This is one of the reasons why building the Panama Canal was so important. Having to go through the Drake Passage was not only a long distance it was very dangerous due to the persistent extreme weather:

https://www.wikiwand.com/en/Drake_Passage

Searching youtube videos for "Drake passage" is also very interesting to see how strong the waves are when travelling via boat through the passage.

This one is also pretty nice: https://earth.nullschool.net/#2017/09/09/1200Z/wind/surface/...

Especially there are many options to play around with (projections, etc)

I found that this one and windy.com give me bad information; something about the plugins I use and/or browser settings I suspect. With windy.com I saw Harvey crashing into Mexico and with earth.nullschool.net I just saw Irma almost directly south of Florida. Since it sounds like windy.com is based on the earth.nullschool.net code, I suspect it is the same issue in both. It seems like sometimes the map and wind layers get out of sync after moving the view area.

https://www.ventusky.com seems to work for me so far.

Wow this site is fantastic. Thanks for relinking. I'm thankfully well out of the path of most extreme weather situations (one of the benefits to the north), but my heart's with everybody affected. It must be otherworldly.

it's only showing about 60 knots (70MPH). is the model off? does the model show higher altitudes? are the news exaggerating?

I'm wondering if it's a limitation of Windy. Their scale only goes up yo 70mph no matter where you are on the map, so I'm guessing that's as high as they can show.

I noticed that too when looking at hurricane Harvey. I use windy.com for sailing, and for low windspeeds, I can say that in my experience it has been pretty accurate.

For any given area you click, I think if you click on the details link you'll see a forecast that shows the gusts. I figure, new broadcasts will use the highest record windspeed for their headline (commercial news outlets being what they are). And you can see gusts that are far higher than nominal when you click on the detailed forecast. I see one area that is nominally 62 knots and gusting to 109 knots (125 mph).

The news generally reports the maximum sustained winds as such, in addition to the maximum gusts. Naturally, the maximum sustained wind speed is not the same throughout the storm - it's mostly in the eyewall. The category rating is based on the max sustained wind speed.

ventusky.com also has all the rest of the metrics as well.

windy, ventusky and some of the others do NOT get wind speeds correctly. At no time during the last three days did they even have winds for Hurricane Irma over 80mph.

Discussion on their forums[0], most upset that these 'visualizers' are more fiction than fact. Also worth noting... getting wind speeds wrong can cost lives.

[0] https://community.windy.com/topic/4415/why-is-wind-speed-in-...

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