Hi,
the first line of the perl script says where the perl interpreter is: #!/usr/bin/perl
You may want to double check that perl is really loacated in /usr/bin/perl.
Another thing you can try is running this from the command line: perl weather
In case the script runs, you can display the path where perl is by running: which perl
One mere thing, double check you have these programs: wget, nkf, iselect and zdbat since they are used by the script. There are links to these programs in the same japanese page you have posted at the beggining of this thread.
Good luck!
Mike