Questions tagged [humidity]
The level of water vapor in the atmosphere. Use this tag for questions about either relative or specific humidity.
77 questions
0 votes
1 answer
201 views
How can humidity drop as it rains?
A Washington DC meteorologist on WTOP radio said that the humidity will continue to drop despite it raining this afternoon. How does that work? Is it normal? It was on Saturday September 6, 2025 ...
2 votes
1 answer
338 views
Given Colorado is so dry, why does it have so much vegetation?
Colorado is arid not only due to its high elevation, but mostly because it's far away from seas and the Great Lakes. Why does western Colorado have so much vegetation regardless? It must obviously ...
- 75
2 votes
0 answers
51 views
Question about humidity gradients
This question may have an obvious answer, but I am having a hard time finding one (and I am very far removed from any physical science classes I previously took). If I have a cup of water in a room, ...
- 21
3 votes
1 answer
278 views
Which is drier, the Sahara Desert or the South Pole?
I would not be surprised if the answer is the South Pole, because it is much colder and the vapor pressure drops very quickly with temperature.
- 215
2 votes
2 answers
993 views
At 100% relative humidity, why does the air still feels dry?
At 100% relative humidity, the dew point temperature is the same as the current temperature. One would probably conclude that water would start condensing on surfaces. But seems that is not always the ...
- 121
2 votes
0 answers
236 views
Is there such a thing as a "warm wind"?
Sometimes, people say things like "It's only $5^\circ\mathrm{C}$ outside, but there is a warm wind, and it feels much warmer" (I live in Austria, a region where there are Föhn winds). I have ...
- 121
1 vote
2 answers
328 views
Why is U used for relative humidity in atmospheric measurement equipments?
RH is the symbol of relative humidity in many textbooks. But, in my experience, U is often used in atmospheric measurements. For example, Vaisala PTU300 means pressure, temperature and humidity. I ...
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1 vote
1 answer
441 views
Why are eastern Oregon and southeastern Washington so dry?
Why are eastern Oregon, southeastern Washington and southern Idaho so arid, as compared to the humid and lush western Oregon and Washington? In Oregon and Washington there is quite an abrupt boundary ...
user29677
3 votes
1 answer
1k views
Dew-point temperature and absolute humidity
I am looking for a reference (e.g. book, peer-reviewed paper) that asserts that absolute humidity is "equivalent" to the dew-point temperature. Such statement should be true, AFAIU. Online, ...
- 133
2 votes
1 answer
676 views
How to calculate wet bulb globe temperature (WBGT) using only temperature and humidity?
Greetings fellow scholars, I'm trying to answer the question above because I've come across WBGT calculators like this one (https://www.climatechip.org/heat-stress-index-calculation) and I don't ...
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2 votes
1 answer
503 views
How to get specific humidity through absolute humidity and height above ground
I'm trying to make a weather simulator using the article Interactive Meso-scale Simulation of Skyscapes. It gives the formula for calculating the mean static energy: $$MSE_i = C_p \cdot T_i + g \cdot \...
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3 votes
0 answers
228 views
What is the "average relative humidity" of the Earth's atmosphere?
What is the current ratio of the amount of water in the Earth's atmosphere compared to its moisture storage capacity? I see values like "a half" or "70% on various web pages, but can't ...
- 1,067
1 vote
1 answer
93 views
Is good rainfall in the UK the result of being a small island surrounded by large moving seas, having mountains and trapped salt [closed]
If the mountains were levelled and salt removed would the country experience as much rainfall? Context Damp in houses: Salt absorbs moisture: think of plaster walls that grow mould from proximity to a ...
- 113
4 votes
0 answers
106 views
What is the definition for a hyper-humid area?
We can use the aridity index $\left ( ai = \dfrac{P}{PET} \right )$ to define arid areas. Hyperarid areas have $ai < 0.05$. Is there a similar threshold for hyper-humid regions? Would it be 20 (...
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4 votes
1 answer
859 views
How to convert specific humidity ERA5 in kg/kg to g/kg or mm/day?
The specific humidity of ERA5 data is kg/kg, but some articles work with this variable in g/kg. How can I convert this? Or to compare with precipitation, evaporation, and other variables, how to ...
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