Think about it. Wind could come from any direction, but not from your back since that's the inside of the house. So, wind could only come from the front or the sides. I'd say you'd only be safe if the wind comes from a narrow angle, about 20 degrees each side between the wall and the wind line of direction. That leaves us with an exposed front of 180 degrees and only 40 of those could be safe.
Now, if you follow my reasoning, you'll conclude that, in a windy day, there's a 70% chance of getting wet. Then again, the wind is also prone to sudden change of directions, or could be just anarchic in its nature.
And as a last ado, you might be having one of those days, in which case chances of getting wet increase by 100%. Trust a stranger: never run outside with yer willie too ready, no matter how many beers you've had.
Actually, the universal language is not English, but poorly spoken English