All this talk about changing strings etc etc is very assumptive, like what would then happen to the many systems that work fine? Some appear to be attacking this from the wrong end, lets work through each progressive possibly.
Looks like you like to generalize ....
"All ..." - I have at least two real-world cases where the inbuilt MB weather network strings were wrong and one is still wrong. Nothing to be discussed about !! You cannot change facts by such generalizing statements !
And - the approach of using personal, customized strings in a http request is safe for everybody - nobody else will be impacted.
Nothing would happen to the many other systems ... Saying that "what would then happen to the many systems that work fine" is building up a scare-crow scenario which doesn't meet reality.
So what's wrong then with this approach ?? - This approach has helped quite a few MB users who otherwise would still be waiting for a solution of their use case.
Especially - as the postings to the other networks based on the same data of the OPer are correct as they OPer states, such an assumption is quite justified.
And if Boris doesn't want or doesn't see the need to change the inbuilt weatherlink.com post - also fine. The customized solution would then still work for the OPer.
If you want to go down another road, feel free to do so. I just offered a working approach. The OPer is also free to adopt it or not.