Author Topic: WS-2800 - How is wind gust calculated  (Read 1193 times)

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Offline Backdraft

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WS-2800 - How is wind gust calculated
« on: November 28, 2016, 10:05:28 AM »
Hi there,

I've have had my WS-2800 a little over a week now and so far it seems to be working nicely, without any major hiccups.
I was just wondering about the wind gust reading I'm getting, as they seem to fluctuate quite a bit.
The manual does not say anything how the wind gust is calculated. The Heavy weather manual has a little more info, but doesn't seem consistent with what I'm seeing.
Heavy weather manual states:
"In the lower section, the Gust value displays the highest wind speed recorded in the past 20 minutes."

I thought this sounded right for what I was seeing, until yesterday when it was really gusty. The reading fluctuates up and down constantly in a period of 1-2 minutes. To my understanding it should not constantly go up and down, only stay the same or go higher UNTIL a set time period (20 minutes?) has passed when it give a new gust reading for that time period.

As I see it I, can't really get any useful info from it, if the gust reading keeps "resetting" every minute.

Would greatly appreciate it if someone explained this to me or do I just have a defective unit.

Offline PaulMy

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Re: WS-2800 - How is wind gust calculated
« Reply #1 on: November 28, 2016, 11:45:24 AM »

I don't have a La Crosse HeavyWeather station but there has been previous discussions on gust... http://www.wxforum.net/index.php?topic=15015.0 and a further link in that thread that may help you to understand.


Enjoy,
Paul

Offline Backdraft

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Re: WS-2800 - How is wind gust calculated
« Reply #2 on: November 28, 2016, 12:37:35 PM »
I saw that thread when searching around. Didn't really find any help on there how the wind gust is calculated. Both threads seem to be not being able to upload gust info on weather sites.

Offline PaulMy

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Re: WS-2800 - How is wind gust calculated
« Reply #3 on: November 28, 2016, 12:43:38 PM »

Quote
"In the lower section, the Gust value displays the highest wind speed recorded in the past 20 minutes."


Would that be a rolling 20 minute period which would change with every data update?


Paul

Offline Backdraft

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Re: WS-2800 - How is wind gust calculated
« Reply #4 on: November 28, 2016, 12:55:04 PM »

Quote
"In the lower section, the Gust value displays the highest wind speed recorded in the past 20 minutes."


Would that be a rolling 20 minute period which would change with every data update?


Paul

Not sure what you mean by this. If it goes up and down several times during a 1-2 minute period, I don't know what the 20 minute period is supposed to mean.

Now it's really calm here and the gust is staying at 0.6m/s with wind speeds of 0-0.4m/s.

Offline PaulMy

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Re: WS-2800 - How is wind gust calculated
« Reply #5 on: November 28, 2016, 01:05:04 PM »

Quote
Not sure what you mean by this. If it goes up and down several times during a 1-2 minute period, I don't know what the 20 minute period is supposed to mean.


I am just making an assumption (and you know what that can make of me ;) ) First 20 minute period from 8:00 to 8:20 showing the highest gust in that time, second 20 minute period from 8:02 to 8:22 with a new higher gust at 8:21 during this 20 min period, etc.  so the highest gust in the last 20 minutes...


Paul

Offline Backdraft

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Re: WS-2800 - How is wind gust calculated
« Reply #6 on: November 28, 2016, 01:32:43 PM »

Quote
Not sure what you mean by this. If it goes up and down several times during a 1-2 minute period, I don't know what the 20 minute period is supposed to mean.


I am just making an assumption (and you know what that can make of me ;) ) First 20 minute period from 8:00 to 8:20 showing the highest gust in that time, second 20 minute period from 8:02 to 8:22 with a new higher gust at 8:21 during this 20 min period, etc.  so the highest gust in the last 20 minutes...


Paul

Hmmm...but that still wouldn't account for the fluctuation. It was going from 10m/s to 3m/s to 5m/s in a couple of minutes.

Offline pfletch101

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Re: WS-2800 - How is wind gust calculated
« Reply #7 on: November 28, 2016, 05:23:46 PM »

Hmmm...but that still wouldn't account for the fluctuation. It was going from 10m/s to 3m/s to 5m/s in a couple of minutes.

Well, it could do that (on the 'rolling 20 minute period' assumption) if (e.g) there was a gust to 10 m/s at 08:00, then little wind until a 3 m/s gust at 8:21, followed by a 5 m/s gust at 8:22. However, the indication shouldn't then be able to drop down below 5 m/s again until 8:42. From your original description, it has been much more variable than that.
« Last Edit: November 28, 2016, 05:25:27 PM by pfletch101 »
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