Wind at 850 hPa This map presents the average wind vector at 850 hPa for every modeled gridpoint (ca. 80 km). The average pressure altitude for 850 hPa is at about 1500m a.s.l. (5000 ft). One can read its present altitude from the 'z T 850 hPa' chart. This map is very useful for gliders and hang-gliders if their airfield or starting pad is significantly below the 850 hPa pressure altitude. (wind-converter)