Temperature At Altitudes
 

Hi folks, I am new to the forum and just joined cause I noticed the depth of aviation knowledge here.

I have a question.
YEARS ago I used to fly right seat with a grizzly old retired Air Force pilot and he had the easiest way in the world to guess temperature at different altitudes. And he was usually pretty close. I have been trying to remember his little method for weeks now and I can't remember it to save my life!

It was real simple, any ideas?

I usually look at the screen in front of me ;)

In all seriousness it's pretty difficult without looking at maps or knowing weather systems in the area. Inversions can put a damper in accurate predictions.

If it's a nice day just subtract 2 degrees/thousand feet from the ground temperature and it should be pretty close

Flight level times 2, subtract from 15 will give you the ISA temp (roughly) for that altitude.

Example: FL 200 x 2 = 40 15-40= -25

Thanks guys, I appreciate it!

Standard lapse, 2 degrees per thousand feet, start at 15 and subtract from there.

There was a special warning today in Alaska for a mass of air colder than -65c aloft :)

I have seen as low as -75C. That was up at 510, but still cold!