There are two ways to upload to WU with a WS-2902.
- You can upload with the console itself directly to WU. This is the best method. It uploads every 16 seconds. You get rapidfire. This is configured with the mobile app you used to get the WS-2902 on your WiFi network. I'll specify which app below. You can't telnet to the console and it doesn't have a built in web interface. You have to use the app.
- You can also upload to WU via Ambientweather.net. This means the console first uploads to AmbientWeather.net (it does so at a max speed of every 60 seconds). Then Ambientweather.net uploads for you to your WU account station ID. This is configured in the cloud at Ambientweather.net. This is not the best method as it relies on Ambientweather.net which is down sometimes and you don't get rapidfire. When Ambientweather.net is down then WU gets no data. Bad option.
Whichever you choose is up to you. But do not configure both. Do one or the other as an upload method to WU. It is perfectly fine to have the console upload to both WU directly and to AmbientWeather.net directly. Just don't have two things uploading to WU. Frankly I don't understand why Ambientweather.net even offers the option to upload to WU when the console is perfectly capable of doing it itself directly, faster, and more reliably. Maybe it is because it is difficult for some people to configure WU Station ID and pass key into a mobile device and it is easier to do so on a computer browser. So maybe it was an option to put a bandaid tech support fix with low tech users. That is all I can figure. But it has complicated things I think because I've seen people unknowingly configure both methods! The problem with that is funky graphs and out of sequence updates and messed up tables.
Whatever you configure in Ambientweather.net is not relayed back to the console as a setting. Having that option in Ambientweather.net may confuse some people in thinking that changes in the cloud get sent back to the console and they don't. There is however an option in Ambientweather.net to send data to PWSweather.com and it is configured similarly to how you would configure WU in the cloud. This however is an added benefit because the console has no way to directly upload to PWSweather.com.*
As to which mobile app you use to configure the WS-2902 all depends on which version of the WS-2902 you have. You mentioned WS-2902 but I'm not certain if you have the original WS-2902 or the revised WS-2902A. The original WS-2902 is configured with the Ambient Weather Osprey Tool app. If on the other hand you have the newer WS-2902A then the app is called awnet, yep just like that with all lower case. At one point it was possible to upgrade the firmware to convert a WS-2902 into a WS-2902A, but this is no longer possible as Ambient removed this capability from the awnet app.
* The console may have no way to directly upload to PWSweather.com but that doesn't stop people from using other hardware/software to then upload directly to PWSweather.com and to many more places.