PWS forecast wins

So in September or October is when I’m expecting to purchase the Rachio Iro. I’m doing it in part of a massive backyard landscape project.

So there’s been some debate over the years about the quality of forecast from the NWS VS Wunderground’s PWS and BestForecast which uses PWS data. Back on Saturday the NWS predicted a hot dry week this week in North Texas.

A cold front was supposed to become stationary well off to our west. Yesterday and today were predicted to be dry according to the NWS but Wunderground’s BestForecast predicted 80% chances of rain for both yesterday and today.

The BestForecast turned out to be correct as yesterday and today yielded anywhere from .5" - 1.5" along with a temperature drop.

It’s true that sometimes PWS information can produce bad data. But then again so does the NWS data as was the case in Bowie, TX last Sunday. The NWS station there produced erroneous temperature drops.

In my city, I know for a fact that the NWS/Airport station uses consumer grade equipment. More specifically, The Texas Weather WR1000. It provides quality information.

Point is, NWS and PWS stations are not all that different in data quality. I think the only real advantage the airports have is the space to properly site the equipment whereas the suburban environment often poses obstacles.

Such obstacles can be avoided though. Wind sensors should be placed high up and unobstructed by surrounding objects. Preferably the roof.

Temperature, humidity and rain should be placed in the middle of a yard 6’ or less above maintained lawn.

Solar sensors should be placed in a location least effected by shadows at any hour of the day.


Feeling much better about our decision to use all PWS data for flex and fixed schedules if user opts in.

After using one by my house, confidence growing. Awesome to see real precip and ET generated 2 miles away

:beers: :rachio:

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thanks for this post. I was originally leery, but looking at it more, I was referencing a NWS over 15 miles away.

Now l’m using a PWS < 2 miles away.

@franz, noticed my previous NWS (KBJC) it was listed as ‘No Rain Sensor’ does that mean it wasn’t recording Precipitation? Because I also noticed my Moisture Level - Precipitation was 0.00in across the board…and as you know it’s been raining a lot here in Denver.

Yes, for some reason quite a few of the national stations do not report precipitation, go figure. There are also some PWS stations that do not report precip data.

cool, thanks for the info.

Switched to: C8926 which looks like it’s reporting precip:

And according to this site seems fairly accurate (at least relatively):

Ya, and if you go to the webapp ( --> zone details --> soil moisture this graph will have observed weather so you can verify that it is reporting correctly. We will get that graph into the mobile asap.