08-20-2018, 06:21 PM
the windy.com site does not seem to have the facility to access archived statistics now, you could have just looked up the maps from the date of the photo until just recently. You will likely find the moisture content of the air at the plane's altitude is 90 - 100% and the dew point and temperature will be similar numbers on days like that . Even during the recent hot weather the temperature between 30 - 40,000ft was 50 below zero and lower .