AccuWeather is a commercial weather forecast company from the US.
The AccuWeather Forums had been around since the early 2000s and disappeared sometime in 2018. No proper announcement was made, but the admin "WeatherMatrix" posted the following in a thread about the closure on 2018-07-16:
Due to the aging software & hardware the AccuWeather Forums is running on, and declining use, we will likely be shutting them down later this year. I apologize for not announcing that sooner.
Volunteer moderators were removed because of GDPR issues that this old software could not route around.
However before anyone gets any ideas, they can still REPORT abuse to me for action :)