Gary - as far as I can see from the results from the queries I asked for 
the issue seems to be resolving why day_archive_wind has the same value AND 
time as day_archive_windGust when in the archive the max for windSpeed and 
windGust are different values.


On Friday, 13 January 2017 15:30:36 UTC+2, gjr80 wrote:

> The SteelSeries Gauges template fields are correct (well the 10 min 
> average actually uses a 1 hour average but that is either here nor there). 
>
> The fact the maximum windSpeed recorded in the archive is lower than the 
> what you get with $day.windSpeed.max is not surprising. The windSpeed 
> values in your archive are the average of the loop windSpeed values seen 
> over that archive period. So if over the first 5 minute archive period of 
> the day your station saw (loop) windSpeed values of 6,8,8,10,12 the value 
> 8.8 (44/5) would be recorded in the archive as windSpeed for that archive 
> period. The daily summaries keep track of the Highs and Lows. So the 
> windSpeed daily summary would record 12 as the max. As subsequent archive 
> periods roll over and loop packets come in additional records are added to 
> the archive (ie windSpeed will contain the average of the loop windSpeed 
> values over the archive period) and the Highs and Lows in the daily 
> summaries will be updated *if a new* High or Low was seen during that 
> archive period. So it is quite possible that the maximum windSpeed value 
> seen in all of the day's archive records is lower than that returned by 
> $day.windSpeed.max ($day.windSpeed.max pulls the max windSpeed value from 
> the daily summaries). In fact for windSpeed i woudl almost guarantee that 
> the max value in the archive will be less than $day.windSpeed.max. The 
> exception is when the daily summaries are rebuilt all of the accumulated 
> detail of highs and lows and their times are lost (ie the detail of the 
> loop data is lost) and the daily summaries are rebuilt frome the (largely) 
> 'averaged' archive data.
>
> The real tell will be a query of both the windSpeed and windGust daily 
> summaries. If you do:
>
> SELECT * FROM archive_day_windSpeed ORDER BY dateTime DESC LIMIT 1;
>
> and then 
>
> SELECT * FROM archive_day_windGust ORDER BY dateTime DESC LIMIT 1;
>
> I'll bet the values in both of the max columns are the same (the maxtimes 
> will likely be different). That is not right and that is why 
> $day.windSpeed.max and $day.windGust.max are returning the same values. 
> (coincidentally, I get the exact same results on my system with a different 
> station so it is not an issue with the station). How weewx handles wind obs 
> is complex, and whilst the issue has been identified I think a bit more 
> analysis will be required to work any possible fix.
>
> Gary
>

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