A Free, On-line, Soaring Weather Forecasting System for World-wide Use

Abstract

Forecasts of the important weather elements to plan a soaring flight are freely available online from a US National Oceanic and Atmospheric Administration (NOAA) website for any location in the world. The pilot enters the location, selects a meteorogram and the forecast model for the period of the flight, then, selects the corresponding forecasted atmospheric profiles and map of thermal depths. This system of products is studied to determine the expected weather. The system has been used successfully to produce convection as well as mountain wave forecasts. Examples of the forecasts and their validations are presented. It was found the ‘trigger’ times for convection are accurate to ±19 min, the maximum thermal heights, minus 81m, accurately represent the maximum achieved altitudes and the climb rates are over estimated by an average 1.4 knots. The widely-used ‘rule-of-thumb’, 1m/s achieved average climb rate for every 1km depth-of-convection, should be interpreted as a maximum value not an average value.