I've already commented about liking the idea behind your app. However, there are some very basic issues, which need to be addressed.
- Changing units from Celsius and Meters per Second, to Fahrenheit and Miles per Hour.
- Local Conditions vs Forcast. The current state only shows a forcasted High and wind speed. However, currently your app is best suited for current conditions and would be made significantly better, if "Current Conditions" is what it displayed. Sure, it'd be cool to also show some forcast data about the day, which current conditions are being displayed for, but first get the "Current Conditions" fixed.
- The simple lack of control over layout, is extremely annoying. An iFrame is a terible way to control such a visually apealing plugin. For instance, the first thing I wanted to do, was adjust the CSS to move it 20px further to the right. Can't do that with an iFrame.
I'm a User Interface (UI) guy, so when I see a plugin with great potential, but a lacking UI, I try to provide some feedback, as to how to make it better. You have a great start, but without these three issues being address, the plugin will not be a suitable source, for weather, in the US especially.
I might also suggest you switch your weather data provider to Yahoo Weather.