What is the difference between surface data and upper air data?
Official surface observations are taken approximately 2 meters (about 6 feet) above the ground. Wind information is taken from a mast approximately 10 m (33 feet) above the ground. All official surface observations must be done by using the standards contained in the FEDERAL METEOROLOGICAL HANDBOOK No. 1. “Surface Weather Observations and Reports” (FCM-h3-2005), which can be found at http://www.ofcm.gov/fmh-1/pdf/FMH1.pdf. For more information on surface observations, see the National Weather Service (NWS) surface website at http://www.weather.gov/ops2/Surface/. As described in the FEDERAL METEOROLOGICAL HANDBOOK No. 3, official upper air observations are taken by a radiosonde, which is an instrument package carried by a balloon. The radiosonde simultaneously measures and transmits meteorological data while rising through the atmosphere from the ground to about 53,000 feet. When the wind information is processed by tracking the balloon’s movement, the radiosonde instrument package is t
