See Red Hat Bugzilla ID 496000 for an explanation.
I don't see any explanation there, nor do I find 90 MB very unreasonable.
Just my opinion. On my OLPC XO-1, with 90% of the internal storage consumed running Sugar on Fedora 18, libweather is the 2nd largest package (after glibc-common). I've only got 100MB free, so using 90MB for a weather-fetching library seems a little unreasonable.
I don't see that anything can be done here, short of not having the data available.