Hello AzulOscuro: Where I live, it can get really hot & humid in the summer & really cold & dry in the winter with lots of snow & ice. Personally I find that my worst time is in the early spring. By then, the last of my energy, from the previous summer, has drained away (as a result of the long cold winter.) So I definitely am affected by the weather.

What is usually recommended for people who aren't able to get enough sun is to take vitamin D. You should check with your doctor before taking this though since it is possible to take too much. Also, if you're on med's it's possible the two could cause an unsafe reaction. There are also special full-spectrum lamps that one can sit in front of. They supposedly help as well, although I have never used one, so I don't know for sure.