# Why is it hot before raining?

What causes the temperature hike before a rain?

I have heard explanations like one that says as the moisture rises, you sweat more.

Can somebody provide a more scientific explanation for this.

• Migrate to Earth Sciences SE ? – StephenG Sep 23 '17 at 14:20
• sorry I mistakenly downvoted your question. I did not want to leave the downvote as this is the only vote so I reversed my vote from $\downarrow$ to $\uparrow$. I'm quite skeptical of your answer but I'll read more. – ZeroTheHero Sep 23 '17 at 15:36
• @ZeroTheHero So, do you think my answer is wrong? I mean it can be. Do provide constructive suggestions. – Krishnanand J Sep 23 '17 at 15:41
• I dunno if it's right or wrong but I'll certainly read more about it. – ZeroTheHero Sep 23 '17 at 15:54
• – ZeroTheHero Sep 23 '17 at 20:33

When warm humid air flows into cool air the humidity is condensed into rain as the warm air cools. The temperature rise your feeling is the warm humid air rolling into your cooler area before it rains. Your body cools itself by sweat evaporating which disperses your heat into the surrounding atmosphere. If the air is humid the sweat cannot evaporate and you retain heat and feel hot.

• @KRISHNANANDJ So basically you invented some pet theory and want to push it. It would be better if you instead added to your question the reasons why do you think this answer is wrong. – OON Sep 23 '17 at 14:57

Rainfall has a cooling effect. However, it becomes hot and stuffy a short while before rainfall. This is because rainclouds gather in the sky. They are saturated with water and do not allow wind to blow.

• Hurricanes have lots of clouds heavily saturated with water, as well as very high wind speeds. Your theory that clouds don't allow wind to blow doesn't hold up. – Nuclear Wang Jan 24 at 19:32

Well, It seems I have an answer to my own question.

I got the answer from my teacher.

I felt it would beneficial to someone like me with the same doubt, and that's why I decided to post it here.

# SOLUTION

A radiation falling on an object gets partially absorbed, partially reflected and partially transmitted.

This transmitted radiation has lesser energy than the original wave, and hence a longer wavelength, according to the equation $$E=h.\frac{c}{\lambda}$$

Let's see the case of the earth.

Normally when radiation from sun reaches earth, a small fraction is absorbed, and the major portion get re-emitted as other electromagnetic radiations.

But when it's about to rain, rainclouds trap the energy , much like "the greenhouse effect".

The solar infrared radiations , which are absorbed by the ground, get re-emitted into the atmosphere as lower energy microwaves.

The rain drops formed have sufficient particle size comparable with the wavelength of microwaves ($1mm$ to $1m$) and thus, scatter back the radiation.

This way, the microwaves reach the ground and gets trapped.

It's these microwaves which increase the temperature of the earth.

The dust particles and the vapours which are present in the atmosphere are also brought down by rain and there is no natural filtration to stop ultra violet rays thus causing heat after rain especially in monsoon because of frequent showers.

• Hello and welcome to our site! This answer appears to have misunderstood the question; you are answering about an effect after rain but the question is about an effect before rain. – CR Drost Aug 15 at 19:14