@Europa, just for the record, my iPhone 5 JB on 7.0.4 also does not whow any weather in the notifications screen. I have checked that I have the Weather app opened and set to use location services in Settings.
It does ok. Lags just a bit at times. But most do a little. I use the free version. I was using Thermometer, but it was all over the place. Fahrenheit keeps up with the current temp as well as my other weather apps. They all have lags at times.