Hi Paul,
no it is correct. It is the maximum average temperature, it is due to the way the updates work, let me just explain again how the updates work:
So lets assume your db interval is 5 minutes.
Your current conditions file is being updated every minute, so you set your CRON to one minute. The data is cached every minute and every 5 minutes, the data is saved to db and cache cleared.
Now, during that db update, what the script does is it uses various methods for particular parameters. For example, in case of wind gust, it saves to db the maximum out of those 5 cached values. For wind speed, it takes the average (since it already is average speed). Pressure and humidity also average etc.
However, temperature is slightly problematic, if it took the average, it could be that your max annual, monthly, all time etc. temperature would not be correct then.
Imagine the five values in cache were lets say 10, 15, 20, 15, 10. Then it would save 14 to db. But your max temperature would then be taken from these averages, even though it was 20 as well.... to overcome this problem, the db actually has 3 columns - T, Tmax and Tmin - I guess it is quite obvious what these correspond to. So upon each update, it saves the avg, max and min.
Then, for the statistics etc. for maximum temperatures it uses the values from the Tmax column, for temperature in general, it uses the T column and for minimums it uses Tmin. This way, it then correctly shows the absolute maximum/minimum values etc.
Now, for this plug in, the values are all taken from the T column, which is the "average temperature". So it really is the "maximum average temperature" etc. However, since the interval is quite short - for example in your case I think you use 1 minute updates and 5 minute db updates - the values between Tmax, Tmin and T are usually very similar and so in long-term, there is no difference when you take like monthly average or so. This is only important when you are calculating the absolute extremes, where the temperature can be different by approximately 0.5°C I would say within those 5 minutes.
Also, as promised, I have added icons for the radar images, you can copy the code of the menu from meteotemplate.com.
