Weather Underground data AND rain sensor?

[RonRN18]

I am curious if there is any reason for having a rain sensor if gathering weather data from a weather station on Weather Underground. Wouldn’t that be redundant? I’m just looking at getting the most out of my system but don’t want to waste money for something that would really not add any value.

[Samer]

Some people use a rain sensor and some use the Internet weather. We support both but as you suggested using just one is probably a more sane approach. Furthermore, the Internet based weather will allow smarter adjustments, etc.

[peter]

I’ve noticed it can be raining and the weather algorithm and still have a % for watering – last night we got .3 inch of rain but was it was showing 66% water level an hour later – by the morning it was zero% – but I clearly don’t wish to water the yard while it’s raining

[Ray]

With WUnderground, you basically have to rely on the accuracy of the weather data reported by them, and it sometimes doesn’t completely match what you observe.

The user manual explains the difference between the rain sensor, rain delay, weather adjustment, and the interplay between them:
https://opensprinkler.freshdesk.com/solution/categories/5000022938/folders/5000147083/articles/5000632569-user-manual-firmware-2-1-5-current-
page 15.

[scottsh]

If it is your personal weather station or a station very close to your house, then no it probably doesn’t make sense to use both.

However, not all weather stations are created equal. My new Davis VantageVue is excellent, but my old Oregon Scientific was hit or miss. In that case I could see using both.

[Author]

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