WeatherUnderground.com: Is WeatherUnderground.com shutting down their service?
No, this is fake news. The rumors are not correct. WeatherUnderground.com is valuable and will continue to host your data.
The API (Application Programming Interface) is moving to Weather.com, but this only effects third party software applications that use the API.
Weather station owners are not effected by the API.
If you need an API, Ambient Weather provides a free service: