Topic: Wind Gust graph stopped working properly because of user error

[gfmucci]

I created a garph with two plots - Wind and Gusts.  Both plots were working fine, the wind a solid line and the gusts were dots above the wind as you see on Wunderground.  Over the previous 20 hours gusts dots were correctly showing up to 11 mph. Then the last several hours the plots for Gusts were dots all along the 1 mph line, while the actual Wind still showed accurate readings of 3 to 7 mph.  It appears there is a malfunction

The average wind speed has fallen to around 2.5 mph.  Does the program stop recording gusts when the average wind speed goes below a certain point?  The same type of graph on Wunderground shows like it should, even for the period where the VWS graph shows bad readings.  My Wunderground station is KFLTHEVI18.

I have a Davis VantageVue.  I've attached a word doc with a screen shot with the Wind/Gust graph stretched out along the bottom.  On the right side of that graph you will see the dots lined up indicating gusts, but the gusts look like they are not registering beacuse they are all on the same axis.

[Cutty Sark Sailor]

All I can suggest is something like this:  It takes time to calibrate VWS vs your actual station location and geography... compared to what 'you think you should be seeing"...

Under "advanced Parameter settings"... mine is set for "Max Windspeed in Database Update Period".... this has proven 'most reliable' for my siting over time... now, you must be careful 'reporting' manually to local NWS office, etc, and await a database update from console, etc... otherwise you are likely to under-report your max gust. Rarely will the 'graph' actually support your 'max'.  Now... the calibration and operation of VWS, and I assume others, DOES NOT resolve itself overnight... this takes time, patience, and attention.. eventually you will have a 'pretty much' calibrated data source.  Like most of my posts, this will be open to challenge, so expect differing opinions.  My experience is you cannot "plug 'n' play' this stuff.. you must 'be a scientist'.. so to speak...

I note that my 'latest' graph at the moment (2:43am ETS)  might appear similar to your reported graph.. I'm too lazy to do screenshot.. but you might also note that this is confirmed and validated by MESO, and other reporting sites.  It's also confirmed, over time, by various 'hand helds'; and nearby stations,...

My point is that VWS will allow you to "modify" readings, over time, to become 'most representativie'... for example, my settings for 'wind speed', 'humidity', etc... over time.. have been 'calibrated' to match location and other varibles.  This DID NOT happen overnight..

So, patience, observation, common sense, etc... you'll have a good station... BUT.. if you DON't report to MESO, CWOP, etc, you have, in my opinion, little chance of, over time, becoming 'valid'... if you understand what I'm saying... Failure to ask questions as you have asked,  is also a 'dumb' move... keep asking.... !

There are a lot of folks who think you should be able to "start' a Vue or VP2, or whatever, and automatically be 'perfect'... sorry.. this isn't the real world... why so many posts on "calibrating rain gauge?"  or "VUE vs COCORAHS".. and all that crap...

One other thing.... DO NOT REVERT TO PANIC MODE if WU has something retarded on your site... many of us have ceased sending to WU, because it's become notoriously unpredictable.  Build your OWN site, let your LOCAL NWS know you're online,.,. WU is NOT what it used to be.!

[gfmucci]

Thanks.

In my case, the gust readings were fine earlier, and then suddenly went bad later.

I think I understand what happened.  In the Advanced Parameters settings, I changed the Wind Gust Calculation from what worked to "Default Station Calculation."  And then, being old, I forgot what I changed after I noticed the gust reading not doing what they should.  So obviously I need to revert the gust settings to what they were before:  One of the other two.

So, should the "default" (when it looked like it was working properly) be "Maximum Windspeed in Sample Period" or "Maximum Windspeed in Database Update Period?"  Again, this is for the Vue.

Thanks for mentioning "Advanced Paremeter Settings."

[Cutty Sark Sailor]

... being old, I forgot what I changed ...

...don't expect that to improve, either... it gets worse    

[gfmucci]

... being old, I forgot what I changed ...

...don't expect that to improve, either... it gets worse    

I take a lot more notes than I used to.  But sometimes I forget to take notes.  Investment tip to self for 2016:  Buy stock in 3M Post-it Notes.

[gfmucci]

So far it appears that the Gust option "Maximum Windspeed in Database Update Period" works best with my Vue.  Please let me know if your experience is different.

[LFWX]

I've attached a screenshot of my settings.

This gives me a reading which shows the maximum gust in the past 5 minutes, which works well with my website which updates every 5 minutes.

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SIDE NOTE - The "Filtered Average Time Constant" inside the "Wind Gust Calculation" box controls the "running average" for all perimeters, not just wind speed. This allows me to display the 5 minute average wind speed, 5 minute peak gust and 5 minute average "feels like temperature" (THW Index) on my site. Displaying the raw THW Index gives wildly varying numbers on windy winter days and the 5 minute average is more in line with the method the NWS uses to calculate the wind chill (using the 10 minute average wind speed).

An example of the varying "feels like temperature" can be seen on a "strip chart" for the THW Index, which I'm showing on this page: http://www.lfweathercenter.com/graphics4.htm