I have my weather widget set to update every hour and it will no longer update. It last updated on June 28. Even if I press the refresh icon on it, it still won't refresh and give me the proper weather.
You can also make sure that your 4G data works, if yes, delete and re-add this weather (maybe it was updated) and yes, the Playstore does have many different widget apps. I'm using HD widgets and it's link to the weather network application , works amazing on my S2x.