Added on: January 27, 2018
Surface observations are an important part of any preflight weather analysis. They provide the latest weather conditions significant to aviation at an airport. Whether in the form of a METAR or by the ground-to-air radio broadcasts, pilots use surface observations to make many routine operational decisions. Prior to taxi, it provides the pilot with an altimeter setting and will likely determine the runway used for departure. When approaching an airport, it will help determine if a visual approach can made or if a standard instrument approach procedure should be executed. And when Mother Nature is at her worst, it will let you know when you should skip the airport altogether and fly to your alternate destination. However, the Automated Surface Observing System, better known as ASOS, has important limitations. In this workshop, we’ll discuss why the ASOS doesn’t always tell the truth when it comes to some precipitation types.