Replies to post #194474 on Tornado Alley (PROG)

[F6]

fuagf -- 60F is generally recognized as the dewpoint level at which folks start to feel sticky/uncomfortable

dew point is a measurement of absolute humidity -- a given dewpoint represents the same amount of water vapor in the air, regardless of the temp (at or above the dewpoint, by definition; the dewpoint of a parcel of air cannot exceed its temperature) and relative humidity (with the temp equal to the dewpoint, 100%, with the temp > than the dewpoint, <100%) of the air, which relative humidity is a measure of the water vapor in the air as a percent of the maximum amount of water vapor the air can hold at its given temp

warmer air can carry more water vapor than cooler air; raise the temp of a parcel of air by 20F and you roughly double the amount of water vapor the air can carry; cut that temp by 20F and you roughly cut in half the amount of water vapor it can carry -- a parcel of air at 60F with a 60F dewpoint (a "saturated" parcel of air, can't carry any more water vapor), 100% relative humidity; same parcel of air at 80F temp with the same 60F dewpoint, relative humidity (roughly) 50%; put the other way, 60F dewpoint air has roughly twice the amount of water vapor in it as 40F dewpoint air -- and of course, cool a saturated parcel of air and the water vapor it can no longer hold has to and does condense out as liquid water; hence, clouds and precip