wind speed graphic meaning

Discussion in 'Mapping & Navigation' started by hotwheels22, Aug 30, 2017.

  1. hotwheels22

    hotwheels22 motorradRP

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    i have MyRadar and Windy which both show info related to wind. i think this is basically speed and direction but i'm not sure how to read the graphic.

    it seems like (?) these two apps show an arrow which is one color (?), but which has a /length/ to the arrows and also a /density/ to the number of arrows bunched together as well as a /speed/ to the arrows.

    i can obviously see the direction but can anyone definitively help out with color, density, speed and length? for some reason i can't seem to figure this out but i'm guessing some or all have no meaning or duplicate the meaning of another graphic or something.

    also, does anyone know at what elevation this info is gathered and /how/ it is gathered?

    THANKS
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  2. hotwheels22

    hotwheels22 motorradRP

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    myradar. same day two different locations/examples:

    IMG_0919.PNG


    IMG_0920.PNG
    #2
  3. CJ3Flyer

    CJ3Flyer Long timer

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    Those are a composite drawing of surface winds created from data collected at a variety of stations that are part of the NOAA network.

    The length and density of the arrows I have always interpreted as an expression of wind speeds. That is to say once in the pink range that is how they express the upper end of the range.

    Winds aloft can be very different, sometimes even from an entirely different direction. I wish my radar would let you scroll through the winds aloft too...
    #3
  4. ohgood

    ohgood Just givver tha berries !!!

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    it will make since to you with a higher velocity example like this one:
    Screenshot_2017-08-30-10-55-45.png

    you can clearly see the northward winds from the gulf getting pulled westerly and reducing speed as they make their way onto shore.

    the slower velocity winds will only be very short lines, and the animated notion helps out a lot to tell what they are doing.

    honestly I stopped using the wind layer a while back and just watch the directions of the current precipitation now. it's usually very easy to tell if two pressure areas will effect each other this way.
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  5. hotwheels22

    hotwheels22 motorradRP

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    hi guys,

    so advance apologies if i missed an answer or if i am being particularly dyslexic.

    i can see the direction obviously - as in the way the arrow (or vector) is moving is the direction of the wind.

    but there is a closeness or density to the arrow/vectors and also there is a length to them.

    is the length telling me speed as in longer is fasten and shorter slower? is density telling me the same thing as i somehow reinforcing the fact that the arrows are longer. this is confusing since the arrows/vectors /themselves/ have speed and presumably faster arrow/vectors is indicating faster wind...

    additionally am i to understand there is a color to them or is the color telling me rain intensity if i have the rain layer on?
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  6. hotwheels22

    hotwheels22 motorradRP

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    guessing here but color seems to mean nothing for wind speed in myradar. in the attached image i turn off radar and the color chart goes away.

    in windy it appears to show wind speed (second image).

    also, length of arrow appears to be due to the speed. basically the length is like a contrail or something where the fast object creates a longer trail. so speed and length ARE the same.

    /density/ of the arrows seems to be unknown metric however in both apps. there is definitely a variation but it is hard to know what it signifies...

    myradar with no rain later on:

    IMG_1045.PNG

    windy:
    IMG_1046.PNG
    #6
  7. CJ3Flyer

    CJ3Flyer Long timer

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  8. hotwheels22

    hotwheels22 motorradRP

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    thanks man

    that's a very interesting link with some interesting work (and links as well).

    again i'm guessing but one of the wikipedia pages mentioned wind "density". seems like there may be a concept/aspect of wind i don't understand but it may be that the density of vectors is showing the "density" of wind...
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  9. Castos

    Castos Castos

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    Windspeed indicators.jpg

    Is this what you are looking for?
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  10. hotwheels22

    hotwheels22 motorradRP

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    hey man. thanks. i saw those and they do look interesting. i think my use of "vector" or arrow may have confused things.

    what i meant is that what i am seeing in these apps makes me think that there is a physical aspect of wind - density? - that is being denoted or signified in these apps by the SPACING of the wind arrows.

    it seems like in most cases the length shows speed and the direction shows direction. but closeness must show "density" (or something) i don't understand.

    for instance here you can see very far apart arrows in utah (as well as short ones), but much much closer lines to the north and in the swirl.

    it may be that not much wind (short arrows) generally correlates with low density (far apart arrows) but these seem like /independent/ metrics...

    Attached Files:

    #10
  11. AugustFalcon

    AugustFalcon Long timer

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    Perhaps the wind streamlines are plotted along isobars, eg, lines of constant atmospheric pressure. So the tighter the isobars, the faster the pressure is changing and the closer the streamlines will be.

    Sent from my LG-H901 using Tapatalk
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  12. hotwheels22

    hotwheels22 motorradRP

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    ooh. sounds tight.

    'streamlines' are the sort of contiguous lines that have arrows of varying length on them sort of tip to tail?

    and each of these is replicating an "isobar" which is basically a contour showing - atmospheric pressure?

    and atmospheric pressure is the /density/ of air taken at some altitude...?

    or am i butchering that?
    #12
  13. Castos

    Castos Castos

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  14. hotwheels22

    hotwheels22 motorradRP

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    interesting. first link is closest and best description i guess?

    isobars are "density" of wind (whatever that is) and wind direction /tends/ (?) to follow the same path as the wind density isobars (i think).

    then i guess the /closeness/ of the wind arrows (showing direction and speed) must indicate how fast (or how slow) the wind density is changing. like the height 'isobars' on a topographic map.

    wow. less confusing now!

    that wind density concept is s little hard to understand. i wonder what goes into it. humidity? not speed i guess since it is shown in the arrows...?

    THANKS
    #14
  15. Knute Dunrvnyet

    Knute Dunrvnyet ...or wait until we get home.

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