Thanks Gary, I did the suggested edit and it's working great now, even showing a green area on the gauge to represent the last 10 minutes windspeed average. I also fixed the maximum wind gust for the day. In the gauge-data.txt.tmpl he has $hour instead of $day...did that edit and now I'm not getting -34999 kmph readings for the max gust....might want to give him the heads up on that too.
On Sunday, 19 February 2017 18:56:18 UTC-5, gjr80 wrote: > > Hi, > > Wind speed can be a complex topic. The simple answer to your question *I'm > wondering if weewx calculates the average windspeed over 10 minutes* is *yes, > it can, but...*. Perhaps an explanation of what weeWX archives and > reports and a few points on the SteelSeries Weather Gauges might make it > clear. > > The WeeWX archive field windSpeed holds the average wind speed over the > archive period. This might be calculated from loop wind speed data if using > software record generation or received directly from the station if > hardware record generation is used. On your install your windSpeed fields > would I expect be averaged over 2 minutes, I have a 5 minute archive period > so mine is a 5 minute average. Stations that use a 10 minute archive period > would indeed have a 10 minute average in their windSpeed fields. The > daily summary for windSpeed is just an optimisation holding aggregates > and other data on your archive windSpeed data, so they to refer to 2, 5 > or 10 (in the examples I cited) average values. That is the data storage > aspect of weeWX. > > The other side of the weeWX coin is the reporting. WeeWX has a variety of > tags that allow generation of statistics over some period of time eg $day, > $week, $span etc. For windSpeed, $day.windSpeed.avg will give you the > average of all of the windSpeed values for the day so far. One could > argue that the average of an average is dangerous, though in the case where > the archive period is homogeneous the calculation is valid (or if your > archive period is non-homogeneous and you are using weeWX 3.7.0 or later > with the weighted summaries fix applied the calculation is also valid as > the values are appropriately weighted). The $span tag allows calculation > of aggregates over a user defined period of time, so > $span($time_delta=600).windSpeed.avg would allow you use the average > windSpeed over the last immediate 10 minutes in your reports, > irrespective of your archive period (of course if your archive period is 15 > minutes, or some value that is not a factor of 10, then the resulting value > will likely be wrong). > > When you hover over the wind speed gauge in the SteelSeries Weather Gauges > the dialog that shows mentions 'Average wind speed (10min)', this is hard > coded in the SteelSeries Weather Gauges (why you would have to ask the > author, though I do seem to recall that Cumulus (once? now ?) defaulted to > what we would call a 10 minute archive period and the SteelSeries Weather > Gauges author is a Cumulus user - I may be wrong). The value that is > displayed against 'Average wind speed (10min)' comes from the wspeed > field in gauge-data.txt. The gauge-data.txt.tmpl file that is currently > included with the SteelSeries Weather Gauges fills the wspeed field using > $hour.windSpeed.avg.raw which would result in the average windSpeed value > for the current hour; not the 10 minute average as labelled in the dialog. > Why? I don't know, it should be changed to > $span($time_delta=600).windSpeed.avg.raw. I will submit a PR to the > SteelSeries Weather Gauges. > > As for the reason why you are seeing a ridiculous wind speed, it is most > likely because the gauge-data.txt file has a null (weeWX None) value for > the wspeed field. When the error condition is showing up have a look at > your gauge-data.txt file and see what value is against wspeed. If it is > null then it is likely $hour.windSpeed.avg.raw is returning None for some > reason. Why would mean looking at your underlying windSpeed data for the > last hour, it may be there is no data and hence None is returned and > converted to null. > > Gary > > On Monday, 20 February 2017 02:22:02 UTC+10, Robert Mantel wrote: >> >> I'm wondering if weewx calculates the average windspeed over 10 minutes. >> My station only gives a 2 minute average and I noticed in my SteelSeries >> gauges, the windspeed gauge when you hover to see historical information it >> shows the windspeed avg (10 min): -35999 km/h or something to that effect. >> Does weewx have a calculation for the 10 average? Not the wind gust but >> the wind speed. >> > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
