On Feb 11, 12:37 pm, wrote:
We've had days here, in the winter, where we've
left the ground where the temp is -20°C, and found -18°C at 3000' agl.

My mistake. It was -20°C on the ground and +18°C at 3000' agl.
A 38° difference. A difference in the "wrong" direction.


Dan