Obs_Sky Wind Question

[btst.online]

In the Obs_Sky data packet, we have:

4 . Wind Lull (minimum 3 second sample) . m/s|
5 . Wind Avg (average over report interval) . m/s|
6 . Wind Gust (maximum 3 second sample) . m/s|
7 . Wind Direction . Degrees

and

9 . Report Interval

Question is… for the Wind Direction, what does that apply to? Does it correlate with item 5, Wind Avg?

–Sam

[GaryFunk]

@btst.online

Does it correlate with item 5, Wind Avg?

Yes, it does. As do items 4 and 5.

[btst.online]

Ok Gary… But, I’m asking if the data for Wind Direction is specifically for Wind Avg?

[GaryFunk]

It’s the average direction of the vector calculation.

You will remember this discussion and the formula I posted.

Calculate wind vector-direction

Here is the code I use to determine average wind direction. Past tests have shown it to match WeatherFow 100%, d is an array of 20 rapid_wind observations and is the formula uses wind speed to “weight” the direction vector. WeatherCalc.calcWind = function(d) { var i, EW_Vector = 0, NS_Vector = 0, gust = 0, lull = 999, s = 0; for (i = 0; i < d.length; i++) { s += d[i][1]; EW_Vector += Math.sin(0.01745329252 * d[i][2]) * d[i][1]; NS_Vector += Math.cos(0.01745329252 * d[i][2]) *…

[btst.online]

Thanks again… just needed that clarification.
–Sam