Is PWS used for evapotranspiration?

[franz]

No. We use forecasted data for ET and then use the closest National station.

Here are more details on how the sausage is made and why.

Weather Underground station not showing up for Gen 3 controller

We use precipitation data from your PWS. At one point we tried using PWS to derive evapotranspiration (ET) but there are multiple reasons why that was a bad idea. I have a rant somewhere around here… We now use the closest national data. It’s worked very well to this point. I’d be sure to pick your PWS so we actively use that for precipitation at your house. Our forecasted data comes from a blend of NOAA, radar, satellite, etc. Hope this helps.