Hi. I've found the bug using sed. There is how to reproduce:
1) Run bash
2) Exec command \
echo weather -5.0 | sed
's/[^0-9\-\.]//g'
3) You will get "5.0". Expected output is "-5.0"

BUT
If you exec
echo weather -5.0 | sed 's/[^0-9\.\-]//g'
you''ll get the correct output "-5.0".

I am using GNU sed version 4.5 on Manjaro Linux.