# What makes it "smell like rain" just before raining? **URL:** \ **Category:** Factual Questions\ **Created:** [May 23, 2004, 10:51pm UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703 "2004-05-23T22:51:49Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![dnooman](https://avatars.discourse-cdn.com/v4/letter/d/839c29/32.png) [@dnooman](https://boards.straightdope.com/u/dnooman)\ **Post date:** [May 23, 2004, 10:51pm UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/1 "2004-05-23T22:51:49Z")
This is before it actually starts raining, so it’s not wet asphalt or anything. Why does cooler, more moist air smell differently? ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [May 23, 2004, 10:53pm UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/2 "2004-05-23T22:53:22Z")
You answered your own question. Moist air carries smells better than dry air. ---
**Author:** ![barbitu8](https://avatars.discourse-cdn.com/v4/letter/b/839c29/32.png) [@barbitu8](https://boards.straightdope.com/u/barbitu8)\ **Post date:** [May 23, 2004, 11:05pm UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/3 "2004-05-23T23:05:19Z")
Usually before a shower, the winds will pick up due to the convection around the shower. The winds will be coming off the rainshower and blowing in your face before the rains begin. Sometimes the shower will bypass you and you’re left with nothing but the aroma…and perhaps the smile. You may get hit by a tear or two, blown in by the wind even if the storm bypasses you. ---
**Author:** ![Ringo](https://avatars.discourse-cdn.com/v4/letter/r/779978/32.png) [@Ringo](https://boards.straightdope.com/u/Ringo)\ **Post date:** [May 23, 2004, 11:10pm UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/4 "2004-05-23T23:10:32Z")
I don’t know much about [this site](http://d.whyville.net/smmk/whytimes/article?id=1760), but it offers this: > [@](#): > > When people say they can smell rain, they do smell something. But is it rain? Ever tried to smell the rain in January when the ground is frozen solid? It isn’t possible. If the humidity in the ground goes above 75%, plants will start to release oils that mix with other earthy smells. Moist air will make it easier to smell this. > > So what do the two have to do with each other? Well, have you ever noticed that oftentimes before a big storm it feels kind of muggy in the air? That’s the moisture that we often associate with rain. Our humidity stays above 75% a good deal of the time, so I’m not sure how precise that is. If there’s lightning before the storm, you may smell ozone. ---
**Author:** ![Ponster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ponster/32/17081_2.png) [@Ponster](https://boards.straightdope.com/u/Ponster)\ **Post date:** [May 23, 2004, 11:19pm UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/5 "2004-05-23T23:19:02Z")
And maybe the winds and moist air are wafting some actinomycetes around which we associate with rain? ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [May 23, 2004, 11:29pm UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/6 "2004-05-23T23:29:32Z")
Close, but no banana. You smell rain because it’s usually rained somewhere before it gets to you, and the winds carry the smell of wet dust, etc to you. Rainwater has little or no smell of it’s own. Peace, mangeorge (Who _loves_ the smell of rain) ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [May 24, 2004, 12:14am UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/7 "2004-05-24T00:14:06Z")
I was just going to say the same thing. The wind that picks up before it rains is coming from somewhere where it has already rained. So various things like cement and plants are wet, and wind blows by them and picks up their odors and carries it to the places where it’s about to rain. ---
**Author:** ![SlyFrog](https://avatars.discourse-cdn.com/v4/letter/s/a3d4f5/32.png) [@SlyFrog](https://boards.straightdope.com/u/SlyFrog)\ **Post date:** [May 24, 2004, 12:56am UTC](https://boards.straightdope.com/t/what-makes-it-smell-like-rain-just-before-raining/246703/8 "2004-05-24T00:56:10Z")
I had always heard that it has something to do with the lower air pressure that occurs prior to a storm allowing the normally lower to earth smell of rotted vegetation and other earthmass to rise higher in the air (I’m serious). I have no idea whether this is true.