There's a new Wind Effect graph on the GPSLog Labs route details Other Graphs tab.

This graph attempts to quantify the effects of wind from different directions on logs along a route. It is intended to assist you to choose a route when bike riding (either to minimise the effect of the wind or to maximise it if you're keen!)

There are 4 lines plotting the relative effect on the overall average speed for the route for different wind strengths. The units are relative and indicative only.

For example, for a log such as the following (predominantly traveling in an east-west and west-east direction):

The computed Wind Effect indicates that the greatest effect will be when the the wind is from the east or west, and the minimum when the wind is from the north or south:

For a route which has a less symmetrical profile, with long sections traveling east and south:

The computed wind effect is more even, but there is a definite advantage when the wind is coming from the west:

The wind model used is pretty primitive and assumes that a headwind has the same effect on your speed as a tailwind, but it's better than nothing. If anyone knows of any more sophisticated models that could be used, I'd be happy to look into it.