Metar reports are generated (automatically I believe unless there's a problem with a runway, etc) by airports all across the world. The latest report for East Midlands Airport is this: EGNX 130850Z 06017KT 020V080 9999 BKN028 10/04 Q1023 What this shows is EGNX = ICAO code for East Midlands Airport 130850Z = 13th day of the month + 08:50 Zulu hours 06017KT= Wind Direction 060degrees, speed 17knots 020V080 = Wind direction variable between 020degrees and 080degrees 9999 = Visibility is 10km or more BKN028 = Broken cloud at 2,800ft 10/04 = Temperature is 10c and dewpoint is 4c Q1023 = QNH, Pressure is 1023hPa All of this information is gathered by the airport and the computer automatically generates what's known as ATIS (Automatic Terminal Information Service), this is an automatic reading of the report in human form (Sounds a bit like the speech thing on your computer) which is then transmitted constantly, 24/7, on a certain frequency. When the aircraft are taking off or landing they can tune to this frequency and get the latest weather information for the airport. In gusty conditions Air Traffic Control will give updates on the surface wind speed/direction due to the risk of windsheer, so they'll usually keep the pilot up to date with what the wind's doing on the ground. As for how Net-weather get it, I imagine they're using Metar.pl which is a piece of software written in Perl which gathers all of the Metar information from every airport which uses Metar from the program maker and then changes it into readable form; such as I did above. Hope this helps.