SkyDemon will automatically add weather and winds to the flight plan based on your planned altitude. Try it for free. I think it is brilliant.
Personally I use the rainfall radar to get a picture about the way the weather is moving, together with
MET'MAP - ORBIFLY FLIGHT SCHOOL - IFR ET CPL AMERICAIN EN EUROPE - FAA IFR AND CPL IN EUROPE for the TAFs and METARs