Radiometric cooling ?
Several members of the site have commented that in some parts of the World our forecast night time temperatures are higher than actually experienced. The reason for this is that we use “free-air” temps. By interpolating down we treat the ground like it’s not there. In reality, at night, snow and dry sand radiate very large amounts of heat energy and so really close to the ground, say a few 10’s of m, it can get much colder than the free-air temp, especially when it is clear and wind is light.
