Why is Wind speed in hurricanes so wrong?



  • @Ottavs Because it is showing averages, not peak measurements.



  • My wind scale only goes up to 60 Kt.



  • @Ottavs Right. It's showing averages. You could have 3 measurements for a city, for example, 50mph, 50mph, and a gust of 150mph. The average is 83mph.



  • Rain scale only goes up to 1.2 in.



  • I think Irma is averaging more than any one component of 60. Sustained winds were reported at 175+. The wind scale offers colors for only up to 60.



  • @Ottavs It's only measuring how much is dropping for that hour, it's not adding up all the rain over time to a single area. 1.2 inches of rain in an hour is a lot.



  • @Ottavs First of all, it's in knots, not mph. Second, sustained wind measurements are much more complicated:
    https://en.wikipedia.org/wiki/Maximum_sustained_wind

    Basically, it's a 1 minute measurement. That's it. Windy is showing you the average wind speed for an hour. They could show you only the max wind speeds everywhere for the hour, but it would likely be very misleading.



  • @Siff Everything you are quoting here comes from research. Now to apply that in mass scale, manage, and sell it cost $$ and I would like ask who do you think is doing that? Who is going to pay for the communications, power supplies, server data gathering, data accuracy, historians, etc... What is out there is what is out there. You are talking about creating and managing a system that reaches the pockets of many numerous political lines and everyone want's to control and pocket $$ for the ability to contribute to the overall success of the best system.



  • @frostymon looking at the wind speed readings at the various sensors. You can see that many of the public sensors reporting valid data up to some time at which either the communications/power/or device has down time. The wind speeds maybe due to the mean of these readings if the data has a good quality else the data is thrown out and the data in time is bad data...not due to the algorithm but the infrastructure.



  • Hola. Para hacer cálculos de viento pueden tomar como referencia el oleaje.
    Tanto el largo como la altura y el desplazamiento, de las mismas.



  • Are Gust measurements smoothed out too or is that real data?



  • @VOLPE-DIEGO interesante



  • Es tan lógico que sea así, como lo es un cálculo de cualquier evento o comunidad. Hay innumerables variantes, dinámicas todas, que sólo permite establecer un mix, un promedio de todas ellas, acotadas también en un período de tiempo. Excelente sitio www.windy.com Lo visto siempre. Gracias.



  • Thank GOD I found this on here. I didn't know the wind speeds were wrong and hubby and I were planning on sticking it out here in our home tomorrow based upon the speeds they were giving.If they are THAT wrong, you should just not have them on here at all.



  • Climate change and global warming are a big lie!
    People are getting more stupid each day!


  • Moderator

    @Ricky_Lightning
    Actual wind measurments are those made from anemometers (windmeters) located on weather stations (mostly airports), on buoys and those made from specialized sattelite instruments. I'm talking about comparing these with the values that gives the model at the same place.
    For example, Key West International Airport is measuring wind from NE (40 degrees) 36 knots gusts 52 kts and the European model (ECMWF) forecasts for the same position wind from same direction at 56 kts.
    0_1505023005699_upload-98e45697-063e-4c7b-a70e-0c9048da0bf8



  • @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.


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