Since I started flying I’ve always been amazed at how quickly the winds increase in speed as you get higher. The site below is well worth checking out if you want to look at wind speeds at various altitudes. It’s a bit like Google Earth, in that you can zoom and pan easily.
Click on the “earth” button (lower left) to look at different altitudes and speeds.
The UAV App can also be useful as you can set it to display the wind speed/gusts at a given altitude (although the slider can be a bit of a pain to adjust in small increments). Useful non the less if you want to quickly check flying conditions.