Based on data from the National Oceanic and Atmospheric Administration's
National Weather Service, Aviation Weather Center at http://aviationweather.gov/.
Raw data is taken from the 6 hour low level forecast Complete FBWinds Product
(continental US) at http://aviationweather.gov/products/nws/winds/?area=all&fint=06&lvl=lo.
Directions: Find the 3 letter identifier for one or more weather reporting stations
near you (in the continental US) at http://aviationweather.gov/products/nws/winds/
and then select the stations in the drop down menus below.