Winter is here, which means it's time for warm clothes, thick socks and getting shocked by everything you touch. What do doorknobs and light switches have against you? Electrons, mostly.
Static shocks occur when two things with different electrical charges get close enough. You see this with door handles, balloons and clothes fresh out of the dryer. It happens in nature, too. Lightning is just a really big static discharge.
These charges get built up through friction, like when you're walking across carpet in thick wool socks or putting those warm flannel sheets on the bed for the winter. And yes, it's worse when it's cold out.
In dry winter air, there's less water vapor to conduct charge away from you. The lower the humidity, the higher the voltage of static discharges.
So now you know — not that knowing will make it any easier to brave the door handle every morning. But there are some things you can do about it. If you take off those fluffy socks, not only will you ground yourself, but you'll also cause less friction as you walk. Or, if you'd rather keep your toes warm, a humidifier can prevent the air in your home from drying out.