# Humidity question

ysterbaard
Science 25 Jan '10 21:25
1. ysterbaard
AAPS forever
25 Jan '10 21:25
When the weather report say: " the humidity is 70% today, but tomorrow it should be 50%" Does it mean the 50% of the air is made up by water molecules? Or is it entirely something else? this might be a dumb question and no I haven't wiki'd it yet.
2. wolfgang59
invigorated
26 Jan '10 08:34
Originally posted by ysterbaard
When the weather report say: " the humidity is 70% today, but tomorrow it should be 50%" Does it mean the 50% of the air is made up by water molecules? Or is it entirely something else? this might be a dumb question and no I haven't wiki'd it yet.
by that reasoning 100% humidity would be water!!
3. ysterbaard
AAPS forever
26 Jan '10 08:52
Yes. That's why I want to know what is the meaning of the term "50% humidity" and how is it calculated. And what happens at 100%. Obviously it cannot be that at 100% humidity air turns into water. Except if you go by wheight. Where a drop of water weighs as much as a whole lot of air. So if at 100% humidity a raindrop falls out of the sky. Still I would like a proper answer.
4. 26 Jan '10 11:04
http://en.wikipedia.org/wiki/Humidity#Relative_humidity

I think that means it's the percentage of the maximum level of humidity that the air could sustain at that temperature.
5. 26 Jan '10 12:18
Originally posted by mtthw
http://en.wikipedia.org/wiki/Humidity#Relative_humidity

I think that means it's the percentage of the maximum level of humidity that the air could sustain at that temperature.
Yes. At 100% humidity, it starts to rain. The actual amount of water air can hold is temperature and pressure dependent; that's why sunny weather tends to coincide with high pressure.
6. sonhouse
Fast and Curious
26 Jan '10 23:07
Originally posted by KazetNagorra
Yes. At 100% humidity, it starts to rain. The actual amount of water air can hold is temperature and pressure dependent; that's why sunny weather tends to coincide with high pressure.
So the part of rain that actually contains the water would be a lot more than 100% humid wouldn't it?
7. ua41
Sharp Edge
27 Jan '10 03:13
Originally posted by sonhouse
So the part of rain that actually contains the water would be a lot more than 100% humid wouldn't it?
I think it's improper to say water is humid
8. sonhouse
Fast and Curious
27 Jan '10 05:33
Originally posted by ua41
I think it's improper to say water is humid
On the other hand, it's certainly not dryðŸ™‚
9. 27 Jan '10 07:30
Originally posted by sonhouse
So the part of rain that actually contains the water would be a lot more than 100% humid wouldn't it?
Your're just pulling my leg, but of course "humidity" references specifically a water vapour in air, not a dispersion of actual water droplets in air.