I think this app is a part of HTC Sense. When i check weather, i get usual report:

But if i swipe down, i get "current" report:

From pictures you can see that reports differ by 2 degrees Celcius, however i once had not only difference in degrees but in day and night i.e usual report showed day while "current" report showed night (or vice versa..? can't recall).
Why there is a difference between both?