Why is Wind speed in hurricanes so wrong?



  • @georgewells It shows me between 100 and 140 mph when i switch to wind and place the "get forecast for this location" marker in the eye wall of the hurricane. Local forecasts are just estimates based off forecast models.



  • Assuming measurements are accurately measured and all else being equal.... Are there any live feeds to watch in Key West?



  • @chibimaddy Seriously? That tipped the scale?



  • @Siff Well, I will to explain without being too technical ... We don't know how to express the solutions of the system of partial differential equations with a formula which can be interrogated at any point at any time. What can be done is to compute an approximated solution. Usually, the method is to use finite elements on a mesh representing the space. The more fine is that mesh, and the more tight is the time resolution the more it will cost in terms of calculations.

    We don't have computers which can go down to 1ms of time resolution, and 1mm³ to represent the space. The size and the time of the calculation with such resolution would show the peak winds but only after a VERY VERY VERY long computation time. A factor 10 in the resolution in space, gives a factor 1000 in the size of the system of equations to be solved. So if you had 1millions equations, chosing a mesh 10 times more fine in all directions, will give you 1 billion equations in place of 1 millions, and this is just for the space. If you do the same for the time also, the factor overall is 10⁴.

    So, the problem is at the end the same as if you want to read the newspaper from space, you need the good eyes for this, to get the right resolution. With a grid in time which is one hour, you won't be able to observe phenomenons which are lasting one minute. Period.



  • We rely on Windy and a couple of other sites for our forecasting. We are sailors in the Caribbean but also used the site for sailing along the coastal USA. We are not meteorologists, we are not computer geeks. We just need factual information to plan our routes which can be 3-5 days. And, factual information so we can run from storms. While I understand most of what is being written, the average person who is trying to use the site for daily forecasting could use some simplified help and data. The site is awesome and is our go-to but it can be confusing for the average person. I have been using the site for three years and still am learning how to use it. I thing that is too long of a curve. And, we do rely heavily on the winds being correct--I had no idea until I read the above that they are averages as I too wondered about the winds in Irma. Is there a tutorial for dummies? If not, could you consider adding one? Thank you.



  • @Mekronid said in Why is Wind speed in hurricanes so wrong?:

    @Siff Trump's budget cuts climate science funding by about 60%. Weather services are downgrading their accuracy accordingly. Also, Tornado and Flood early warning systems will be completely dismantled. Republicans are getting what they voted for.

    TYrump is an awful person and even worse president, but that has nothing to do with windy being inaccurate.



  • No forecast model is 100% accurate and to believe they are is a pipe dream. Hurricanes are living, breathing weather events and change almost as rapidly as most people change their minds. Maybe one day someone will develop one that is 100%, but for now I watch Windy, as its the best available, for now.😏



  • How can i chane metric?



  • @BodorSoft
    press "menu" (the 3 horizontal bars at the upper left)
    and then press "settings"





  • @Mekronid RU F'n Kidding me here!?!?! What a bunch of CRAP! That's like saying we here in Texas & Florida deserved Harvey and Irma!!!!



  • @julienmary Well Done! U made it sound solve able. Nearly maybe?



  • @meteo-GR I'm not sure the amount of resources reportedly correlating all of this data is as extensive as you believe. Just my opinion bro. Peace. Stay safe.



  • @conduit I am neither qualified nor remotely intelligent enough to appreciate your invitation to understand the math! Hee Hee. Cheers anyway.



  • @conduit It would be a good idea for someone knowledgeable about the mechanics behind this app to produce a Q&A page answering the most sought after questions/functionality



  • @chibimaddy Firstly - Good Luck these next few days from Me & mine to U & U'rs. I hope to see you back here in the next few days discussing the joys of Windy.com



  • @cape I am in total agreement with you there. It's got loads of functions and looks great too. Pro version?


  • Moderator

    @Siff

    Hello, I'm in Sint-Maarten and I survived Irma (My house didn't). REAL wind values have been constantly updated, thanks to NOAA planes flying through the hurricane constantly. They are today the only way to give us real wind data during such storms (because instruments on the ground fly away). During the peak intensity just before Irma hits sint maarten, they measured 225 mph wind gusts in the eyewall of the hurricane, and sustained wind of 185 mph. We had an anemometer here in Grand-Case airport. the last wind gust measured by the instrument before it broke was 135 mph 2 hours before the eyewall. Everything is destroyed here.

    Models like GFS and ECMWF cannot predict hurricane winds, especially close to the eye, where the wind is the strongest, because the resolution scale of these models is not wide enough (this is the main reason to me). In the front of the hurricane, there is northerly wind with strong updrafts, 7 kms away, in the eye there is no wind and a strong downdraft, and the 7km away there is a strong southerly wind with updrafts again ! All of that with huge changes in pressure. It's so powerful in a so small area ! That's why they created the Hurricane Weather Research and Forecasting model(HWRF). It is the only model using recon aircraft data, satellite imagery and buoys data at the same time !!! And it is the more precise model to predict hurricane wind direction and force (not the path of the hurricane).

    So, regarding wind force and direction, the more you are close to the eye, the more GFS and ECMWF model will be inaccurate. But these models are better to predict the path of hurricanes, they work well on bigger scales !



  • @Siff I am questioning the reasons for the HUGE discrepancy between the supposed wind speeds proclaimed by "The Weather Channel",(150-165 mph), and those which are found on the "Windy" graph.
    Something is not Kosher here.
    Florida is Not being "whipped" by category 5 hurricane winds.



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