Wind arrows direction

Reply to Wind arrows direction on Wed, 27 Feb 2019 06:07:52 GMT

Gkikas LGPZ — Wed, 27 Feb 2019 06:07:52 GMT

.... also here, all symbols show the same wind speed (25 kts)

Reply to Wind arrows direction on Wed, 27 Feb 2019 06:06:16 GMT

Gkikas LGPZ — Wed, 27 Feb 2019 06:06:16 GMT

@Rodnet
Wind symbols at lower levels (e.g. at 1000 hPa) are shown relatively smaller
than the same symbols at higher levels.

Reply to Wind arrows direction on Tue, 26 Feb 2019 22:15:07 GMT

Rodnet — Tue, 26 Feb 2019 22:15:07 GMT

@Tomber42 hi Tomber, on my windy app, the forecast is showing a barb about half the length of all the other barbs with a line about half the length of the 5knt line, does that mean less than 5knt
Thank you

Reply to Wind arrows direction on Tue, 26 Feb 2019 17:21:17 GMT

Tomber42 — Tue, 26 Feb 2019 17:21:17 GMT

Here another explanation how to read wind barbs
http://weather.rap.ucar.edu/info/about_windbarb.html

Reply to Wind arrows direction on Mon, 25 Feb 2019 08:13:01 GMT

siim — Mon, 25 Feb 2019 08:13:01 GMT

@xiyakl must be trolling here.

For interactive data rich map Windy has made good choice with wind arrows.

Reply to Wind arrows direction on Mon, 25 Feb 2019 07:19:25 GMT

xiyakl — Mon, 25 Feb 2019 07:19:25 GMT

@idefix37
Well, really you're so way off, beyond help.
I like the old charts you found on Google, nice bit of research. I think you nailed it.
In case we end up discussing chemistry I decided to play the trump card early, because I've got this, which by its vintage has to evidence of something, right?

There's such a list of reasons as to how come your wrong, but on casual examination apparently right, that there not time in a productive day.
I would say though, you got a bunch of pilots laughing our asses off.
I was thinking to donate something useful to this outfit, but after seeing the (now shrouded) unethical conduct in 2017, and the determination to stay wrong/in-toytown, the taste seems all gone.
The right thing to do if so obvious, but somehow invisible for some because operating in a standardised manner is some kind of anathema.
The little arrows you're so keenly advocating for are just hokey little things someone has just made up in their head.
It's a toy and something like this it's diagnostic.
Now here's a question for you. Given we are at an impasse, do you need to have the last word? I'd say I've got money on it, but nobody here will bet against.

Reply to Wind arrows direction on Sun, 24 Feb 2019 21:58:54 GMT

idefix37 — Sun, 24 Feb 2019 21:58:54 GMT

@xiyakl
Yes, exactly, you must imagine an arrowhead in the circle. The old drawings of windbarbs were showing an arrowhead, as this first french isobaric map from 1863.

Then a circle has been used together with the arrowhead, as this American map from 1888.

Finally the drawing has been simplified and the arrowhead has disappeared. But you must remember that the « windbarb » symbol is based on an arrow drawing with an arrowhead and feathers or feather barbs at the back.

So you may consider that the arrowhead is no longer used to show the direction of wind by official weather offices according to WMO recommendations, but is still used on Windy app. For a west wind, blowing from the West, the arrowhead is oriented toward the East ! The direction of a west wind is NEVER given by an arrow pointing to the West, even if the wind bearing is 270° on the wind rose. So the way how Windy app represents the observed wind direction is correct and is not «180° out of phase » as you said.

OK, Mate? Is it clear for you now? So you may explain to your colleagues why the way how Windy app figures wind direction at weather stations is correct.

Reply to Wind arrows direction on Sun, 24 Feb 2019 02:27:32 GMT

xiyakl — Sun, 24 Feb 2019 02:27:32 GMT

@idefix37
You do understand the pennants go to windward, right? The little circle isn't the head of an arrow or something like that.

Reply to Wind arrows direction on Sun, 24 Feb 2019 02:21:12 GMT

xiyakl — Sun, 24 Feb 2019 02:21:12 GMT

@WXcycles
Lols

Reply to Wind arrows direction on Sun, 24 Feb 2019 02:10:30 GMT

[[global:former-user]] — Sun, 24 Feb 2019 02:10:30 GMT

@xiyakl

You could just look up the Doppler.

Reply to Wind arrows direction on Sat, 23 Feb 2019 12:14:36 GMT

xiyakl — Sat, 23 Feb 2019 12:14:36 GMT

@idefix37
Makes us, formally speaking, polar opposites ha

Reply to Wind arrows direction on Sat, 23 Feb 2019 11:19:50 GMT

Gkikas LGPZ — Sat, 23 Feb 2019 11:19:50 GMT

@xiyakl
What do you think is the wind direction over North Sea (today) ?

Reply to Wind arrows direction on Sat, 23 Feb 2019 11:30:18 GMT

idefix37 — Sat, 23 Feb 2019 11:30:18 GMT

@xiyakl
Instead of long explanation you'd better show a screenshot of what you want to explain.
The arrows shown at weather stations for the observed wind show the same conventional direction as the wind forecast which is displayed by the « animated particles ».

Then, here is the way how the wind direction is shown at a station for a WSW Wind:

And how Windy figure a wind with the same direction:

For me these two ways to show the wind direction are absolutely consistent.

Reply to Wind arrows direction on Sat, 23 Feb 2019 11:55:45 GMT

xiyakl — Sat, 23 Feb 2019 11:55:45 GMT

43.gif/84a928a8-3389-4690-8453-005a9c15f906?t=1369746553556)
..or:

..or:

..or, well, maybe that's enough.

Reply to Wind arrows direction on Sat, 24 Jul 2021 08:34:34 GMT

idefix37 — Sat, 24 Jul 2021 08:34:34 GMT

@xiyakl
You said that the « last response is utterly incorrect, and the barbs example image given has been completely misconstrued by the author ». Sorry to say that you are wrong!
And be sure that I use to « sail beyond passive crewing » and that I do « not confuse the rule for reading wind barbs ».
Here is a map using the traditional way of showing wind direction around a low in the north hemisphere.

Compare it with the way that Windy show the wind flow around a cyclone. For example today near the Azores archipelago.

There is no reason to change the « animated particles » on Windy. This should be really crazy to do it !

Reply to Wind arrows direction on Sat, 23 Feb 2019 13:18:12 GMT

xiyakl — Sat, 23 Feb 2019 13:18:12 GMT

@xiyakl
BTW, here's the wind barb image from NOAA, reflecting WMO standard (https://www.wpc.ncep.noaa.gov/html/stationplot.shtml), which an earlier author posted as explanatory. I think this is the source of earlier confusion. Note the text ('outer' is relative to station position, in other words, the foot of the barb is at the station, the barb points 'out' into the wind, not along) above the image reads:

"Wind is plotted in increments of 5 knots (kts), with the outer end of the symbol pointing toward the direction from which the wind is blowing. The wind speed is determined by adding up the total of flags, lines, and half-lines, each of which have the following individual values:

Flag: 50 kts
Line: 10 kts
Half-Line: 5 kts

If there is only a circle depicted over the station with no wind symbol present, the wind is calm. Below are some sample wind symbols:"

Reply to Wind arrows direction on Sat, 23 Feb 2019 04:36:38 GMT

xiyakl — Sat, 23 Feb 2019 04:36:38 GMT

@idefix37
Sorry but this last response is utterly incorrect, and the barbs example image given has been completely misconstrued by the author.
I came across this thread trying to find anyone who'd raised the issue before, having been a bit confounded by it myself.
@svsecondchance is right, Windy.com vanes are 180° out of phase; @idefix37 is very wrong, vanes_always_point into the direction of flow, this is a convention since first use of the wind rose. Anyone who's ever sailed beyond passive crewing could not confuse the rule for reading wind barbs, especially given the powerful feedback even a motor launch gives from actual winds.
I think the mistake here is confusing vectors for vanes. On a chart displaying vectors there are arrows, yes. N.B. however, vector arrows have a set form, and representing a vector they convey direction and magnitude, i.e. velocity.
For Windy.com to correctly display winds using arrows pointed along flow direction would require adhering to the international conventions for displaying meteorological data, which are published by WMO, in other words, thin arrows with relative velocities represented by center line length.
Note also, vector maps have equidistant data plots. Anything with direction display set to station locations is not a vector chart.
It's just a hokey idiosyncracy given the app/site is a toy, but it's wrong and as such, should be fixed.
Showing colleagues the app, everyone points out this as the first deficiency they notice.
It's a bit surprising that there could be any diversity of views on something so elementary as the global standard for representing wind data, but as we all know there's really no limit to how wrong each of us will be about things at various times of the day.
The arrow mixup should be fixed pronto. It's not hard, just reverse/change the symbol. If anyone needs help with the coding my neighbour's 12yr old can do it, I'm pretty sure.
I bet, though, the issue is well known, but leadership paralysis set in at the '..but what will users do when the symbols they're used to suddenly reverse polarity?'. I say this after finding other discussions about wind direction issues here, where people fear users might confuse 300° for 300°F (I'm not joking, just search this forum).

Reply to Wind arrows direction on Thu, 06 Dec 2018 14:30:44 GMT

idefix37 — Thu, 06 Dec 2018 14:30:44 GMT

@svsecondchance
That’s absolutely normal. The arrows are in the same direction of the « particule animation ». In the conventional way to show the wind direction i.e. with the arrows type called « wind barbs », these arrows are also in the same direction of the wind flow and not from where it come.

Reply to Wind arrows direction on Thu, 06 Dec 2018 13:58:56 GMT

Marienka — Thu, 06 Dec 2018 13:58:56 GMT

Hi @svSecondChance , can you please send us a screenshot of the situation? Also what device + OS are you talking about? Thank you.