This site references the closest weather station to the selected track. Same as bringing up your local weather on your phone.
Depending on your location, local weather can be several to 30 or more miles away. Typically they are only updated a few times per hour.
This is fine for "ball park" weather and if you are only interested in a "ball park" ET prediction.
If you are interested in being able to predict a level typically necessary to go rounds, we offer a line of highly accurate PerformAIRE weather systems that provide up to the minute information.