I guess this boils down to what is my goal. Here's two plausible goals from my perspective. I go to DDG and ask for it to give me a sample of some sources from which I could find the weather. This is a traditional search. Or, I could go to DDG and ask it for the current weather. This is what I really want.
There's no scenario in which I already know which weather source I want to use, memorize its ! command, navigate to DDG, then enter that ! command. That's too many jumps. If I want the weather from weather underground or whatever, why would I ever go to DDG to start with?
I have DDG as my default search engine, so I just type "!wu 01234" in my address bar. This basically skips the DDG navigation and UI entirely. I like this type of shortcut for Wikipedia and IMDB too.
Anyway this is just a workaround for when the weather infobox doesn't automatically show up in the DDG UI, which it normally does.
Weather.com is pure evil when it comes to tracking and clickbait. It's also slow as hell.