I think it's not accurate because its set to one location and it doesn't change. I'll see if I can figure out where exactly that line of code is and if I can change it based on the native weather widget or by looking into code from Forecast.About 1/3 of the way down, there's a heading:
<!-----Weatherscript----->
Under that, there's a section: var updateInterval =15
You can change that. The weather's not seeming to accurate for me, though.