Science Explains Why Rain Makes Us Feel So Tired

Rain is like a cosmic lullaby tapping its beat on the rooftop. There are those who want it to go away and others who bask in the glow of its puddles, sharing umbrellas and admiring the deep gray patterns in the sky.

Precipitation seems to affect our moods in one way or another. But is this true, or is it just the work of our collective imaginations? Does a gray day really make us blue? Does it truly shift our focus, relax us, or make us drive like maniacs? One common observation is the fact that rainy days make us all want to nap (via Sleep Health Group).

It's almost a hypnotic feeling that takes over as soon as the drops fall from the sky, streaking our windows and bringing on the sudden urge to crawl right under the blankets and be off to sleep. As it turns out, there are several scientific explanations for why rain makes us feel so tired (via Green Matters).

Pink noise is nature's sleeping pill

According to Wonderopolis, when rain produces that hypnotic pitter-patter against your windowsill, it creates something called pink noise. Unlike white noise, which is disruptive and unpredictable, pink noise is the equal distribution of the frequency of sound. Pink noise is evident not only in the rain but also in the rustling of the wind traveling through the trees and the soft, rhythmic soundwaves of your own heartbeat.

Of all the different colors of noise — which include pink, white, and brown — pink is the noise that induces and also improves the quality of sleep (via National Library of Medicine). Don't feel bad if this reduced brainwave complexity carries you away to dreamland. ScienceDirect reports that taking a nap under the umbrella of pink noise can improve acoustic stimulation, which can lead to improved memory. So, the next time you feel a rainy day nap coming on, you might want to memorize a few vocabulary words before crawling back into bed and then see if you still remember them upon awakening.

Dark skies and the humidity rise

Did you ever notice how the sunlight on a bright day seems to lift your spirits? This, too, is no figment of your imagination. Rather, it is a chemical reaction to the sunlight that increases your level of serotonin, according to Time Magazine. Since rainy skies are void of sun, the darkness that envelopes a stormy day produces an entirely different hormone, namely melatonin, which is associated with sleep (per Sleep Health Group).

While the decrease in serotonin and the increase in melatonin cause some people to feel down or blue, the most common reaction is to feel drowsy. When you add to this the atmospheric pressure brought about by high levels of humidity, a rainy day can often make you feel not only drowsy but also heavy, from your eyelids down to your toes (via Green Matters). No wonder a midday nap is on the horizon of many a gray and rainy day.