You should start by reading the documentaion if you're having problems with PHP Weather. After you've done that, then try the mailinglist at SourceForge. There's two maillinglists in use at SourceForge, although you can only post to one of them:
This list is use for all sorts of questions and discussion about PHP Weather. People can come here asking for help (for problems with both version 1.x and 2.x) or we can discuss the development of PHP Weather.
The list is generally a low-volume list, but this depends on how much work we're doing on PHP Weather. There has been periods with only a single mail or so each month, and there are periods with a couple mails each day.
If you're using the CVS version of PHP Weather, then you should subscribe to this list. Everytime the sources are changed in CVS, a mail is sent to the list with the differences between the new and old version of the changed files.
The amount of mail that flows through this list is (naturally) very dependent on the amount of work being done on PHP Weather. But you should probably prepare for a couple of mails a month, and several mails each day when we're really busy.
Please note, that you have to subscribe to the lists, before you can post to them. You're only allowed to post to the lists from a subscribed address - this is to prevent SPAM on the lists.