Metrics Explained

There are lots of metrics within a myWindsock forecast. Here are some of the key metrics that will help you understand the weather conditions. Many of our propitiatory metrics are an attempt to quantify the conditions for cycling.

An important point to understand is Air Speed. This is the speed of air flow when apparent wind speed and rider speed are taken into account.

Click to view animation explaining Air Penalty.

Air Penalty

The difference between the amount of air you have passed through and the distance you’ve ridden along the ground is your air penalty. More information can be found on the ‘Air Penalty Chart‘.

Air Distance

The distance of air calculate by Air Speed at time exposed. Tail winds will produce a lower Air Distance than Ground. A headwind will produce a greater Air Distance than Ground Distance.

EAS Time

Given the Effective/Apparent Air Speed we calculate the time to complete the ground distance at this speed. This is essentially how long your ride would have taken on a calm day.

Weather Impact™ (wImpact)

On a windy day, you will likely find that your bike ride is slower than it would be on a calm day. wImpact calculates exactly how much slower (or faster) a completely calm day would be. A more detailed description can be found here.