You’re accusing a well-respected government agency of publicly lying. That’s a strong claim. What possible reason would they they have to do that?
And before you say the US Government lies all the time, this is the National Weather Service, not the CIA. They’re about the as non-partisan and trusted as you can get. They don’t run psyops programs, they provide massive piles of free and valuable scientific data to the public every day. They devise sophisticated weather models and run supercomputers. I think they probably know how to use an API.
They manage a large number of region-specific accounts, so that users can follow just the regions they care about. I imagine the cumulative total exceeds the API limit.
This is a pretty common pattern. Daryl Herzmann's iembot accounts are in a similar situation, I think.