Download it here
ForeCastr gives you a 3 hour forecast based on your current location and displays it alongside all of your other datafields
For Registered WindField owners, it will update every 15 minutes. For everyone else, it will update at the beginning of your ride and continue to show that same data for your entire ride.
Optional fields can be configured to show temperature, humidity, windspeed and other values.
Settings are accessed thru the Garmin Connect app on your phone. Registered WindField users can add your email address in the settings to enable the 15 minute updates.