So if I understand correctly, the percent adjustment is based on current temperature along with humidity readings per the local weather forecast.
Here is a scenario that I propose: instead of using the current temp and humidity settings to make a percent adjustment, how about using the hottest temp for the day to make the adjustment?
So if I have a program set to run at 6am, the current temp does not matter, it should examine the weather report and see that at 3pm it will be 95 degrees and water accordingly. If the program is running in the evening past the hottest temp of the current day, it should look to the hottest temp of the next day to determine percent.
If I understand it correctly, you mean using the ‘forecast’ highest temperature for the calculation, is that right? I think this is doable, as long as this is available in the data returned from WUnderground API. Currently the algorithm uses the ‘average’ temperature of the previous day, defined as the average of the highest and lowest temperature of the previous day. This is readily available from WUnderground data.