Temperature/Dew Point Spread | Water Vapor in the Atmosphere | Lowest Condensation Level

A snippet from our first ever Ground School on water vapor and condensation levels

[TudorRavoiu]

This must be the best explanation on dew point, rh and spread, I've ever heard. The coffee comparison was really helpful!

[jbaker]

Even as an aside to aviation, this is just an amazing explanation of how clouds themselves form.

[philadelphia]

I watched a good number of videos like this and this was no doubt the best and easiest to understand. Much appreciated.

[jackmosher]

...wow, the coffee analogy was absolutely on-point!

[LEKSANDER]

Great video, I would like to clarify for other viewers as to "Why is it true that cold air cannot hold as much moisture as less cold/warmer air"? The reason is that cold air has less energy than warm air, warm air has particles which are vibrating faster and that produces heat while cold air has less of that and much slower.
When a water vapor molecule enters a warm air parcel, it is allowed to stay as water vapor because the heat difference is not great enough to "suck" the heat out of the water vapor and turn it into something with less heat (liquid or solid).
When a water vapor molecule enters a cold air parcel, the difference in temperature between the water vapor molecule and the air parcel is enough to "suck" the heat out of the water vapor molecule and transform it into a state that requires much less heat energy to maintain (liquid and solid).

[thebadgerpilot]

I’ve always understood this, but the coffee reference is an excellent way to actually visualize it and and put it in terms people can relate it to. I was actually drinking coffee when I watched this (I take my coffee 0% saturated). Non coffee drinkers could probably relate to making hot chocolate with the powder packets. Or… what kid hasn’t ever tried to see how much sugar they could dissolve in water and drink it?

[pedrodasilva]

Thank you for that brilliant explanation

[cletus]

I just had an exam on this yesterday. Great breakdown!

[nicholasbarbier]

love the analogy with coffee and sugar, well explained

[alk]

So why does the dew point fall slower with altitude than the temperature? Is that always the case?

[AlexandreHenriquePinheiro]

This was the best. Thanks so much for the explanation!

[joshcaligaris]

I swear, i can watch 10 different videos on any topic and not understand it. I come to this guy and he explains whatever topic i need, perfectly.

[eliaselhaddad]

Why does Dew Point decrease as temperature decreases. What are the theoretical reasons?

[RicardoCerveraBlanco]

So in order to condensate or dehumidify the water from the air the temperature has to be lower than the dew point?.

[damonbaggs]

Not the whole story....and in my experience, not as simple as this explanation makes it out to be. I've seen temp/dew point at zero without the formation of "clouds" or fog more times than I have see with the same temp/dew point at zero with clouds or fog. So, this "within two degrees or less temp/dew point spread will create fog/clouds" isn't the entire truth. I personally don't know what other variables there are to this phenomenon... I just know there is more to it. Also, I've witness the TAF or MOS more often wrong with the prediction of fog then they are right.... so, there is that as well.