IMHO I still like the concept of a physical rain sensor. The data does not lie, and is not affected by a lapse or gap in reporting precipitation data. I view it as a type of cheap insurance.
A PWS is very helpful for flex schedules in having the most accurate weather data, along with fixed schedules for having the most accurate recorded precipitation data.
@Skywatch, hope to see you become a user next month 
. Please let us know if you have any questions we can help answer.
@cfwiggum, good point! Thank you for confirming.
@jimB34m, sorry for the delay in getting back to you. Any luck on calibrating your Iro?
@dentalpain, please keep us posted on your water savings! We love hearing his feedback from our users.
@plainsane, totally agree! It’s a very cheap insurance plan for anytime the forecasts are wrong.
@dentalpain, great questions. Rain forecasts are tricky to understand. According to the U.S. National Weather Service (NWS), POP is the probability of exceeding more than 0.01 inches (0.25 mm) of precipitation. Additionally, while the forecast might call for 1/2 inch of rain, if there is a 100% probability of rain covering one half of a city, and a 0% probability of rain on the other half of the city, the POP for the city would be 50%. A 50% chance of a rainstorm covering the entire city would also lead to a POP of 50%. The POP can be expressed as a combination of degree of confidence AND area coverage. As you can see, the variables start to add up and there’s a limit of analysis paralysis 
A rain sensor does not replace a PWS. It simply will interrupt the common wire anytime it senses moisture and disable the controller from functioning. Think of it as an insurance policy for bad weather forecasts.
@plainsane, good to know. We’ll reach out to our weather service provider to see if there’s anything that can be done to speed up the data transfer.
Thank you everyone for your feedback and support. Please keep this conversation going if you think of anything new to add!
Best, Emil
it is transient and uncommon, I’m assuming it is the weather station I’m using is lagging. More often than not it is micro climate that runs it in the rain or shortly after rain. But it has happened 1 time for certain.
I’m installing a pws at the end of the winter break, I was really just trying to illustrate that fact that there can be things outside of rachio’s control that would necessitate a sensor to avoid running it in the rain.
Yes, thanks Emil. Seems that the rain gauge, for the Netatmo, was low by about 25%. Haven’t gotten a chance to do another catch cup comparison test though.
@jimB34m did you calibrate your Netatmo rain gauge or just connect it and use the default settings? I calibrated mine and it seems to be reasonably accurate. Calibration settings are found on website under settings (gear icon) -> calibration.
I connected it and used it for a few weeks without knowing if the calibration was off or not. I then read a bit on Netatmo’s forums about how they tend to be way off, out of the box. When rain was predicted, I set up a catch cup and compared my own calculation to my rain gauge and confirmed it was off. I then did the steps you posted above to calibrate it. Just waiting to do another catch cup test and compare it, so I can see how I did in the calibration.
