yes, this is a known issue and i have run into it countless times, htc SHOULD get their asses in gear and update their existing software instead of focusing on rushing out half-assed phones like their windows phone 7 phones(IE HD7 and surround) but that is neither here nor there... the solution to many headaches with this cursed widget is this......
remove widget from home screen then tap menu > settings > applications > manage applications > All(or menu > all, depending on OS on phone) scroll to Clock by HTC (***NOT Clock Widget***) and tap on it, from there, clear data and ensure it reads as 0KB of information (if not then power cycle phone and repeat steps until it does then return to home screen > hit + button > tap Widget > scroll down and select clock by HTC (***NOT analog clock***) > scroll to the right twice to get the right clock with the weather > select it > tap Add City > put in your city or larger city nearest you that would get the same weather as you > select that city > leave the full screen animation on cause lets face it, its pretty damn cool > enjoy your updated widget with YOUR weather being read properly(this may take a few moments or a power cycle of the phone to get it to read but this has worked for me personally and for others I've helped many times over...
everyone please enjoy this little golden nugget of information and remember..... Google contacts sync to GOOGLE and Phone contacts sync to your outlook on your PC, they will not cross-sync without unsupported third party software so don't try

, HTC apparently hates Macs so don't look for any help there or with linux because no one seems to like them at all.