The sky is grey and I am blue

Is there any scientific explanation why we feel blue everytime the rain pours? Is it because of media? Is it because it's almost always raining during the saddest part of a movie? Breaking up of lovers...a loved one dying (at worst, shouting his/her name) Or is it just us trying to compare ourselves with the sky and the rain? The world suddenly loses its vibrance. After a month long of scorching heat (and sweaty underarms, hehe), here we are again, getting our ass fat with champorado and tuyo, magnetized to our warm beds, and slouched on our couches watching DVDs the whole day. Most people find this season boring and I'm one of them; missing the stuffs you love doing under the sun. But don't you sometimes find it relaxing? Having you only for yourself, no other people to bug you, no feelings getting hurt, no ideas being rejected...All your mental torments (that's a hard one) being washed away as you imagine yourself drenched under the grey sky (singing laughter in the rain, hahaha). Right now I'm here in the office, listening to incognito (which is just right), imagining myself having a warm coffee, reading a good book, petting my dog, being in my calmest state, nothing to worry about. Well, it's all just imagination, break's over, still have things to do.