In Finnish mythology, Ukko was the god of the sky, weather, and the harvest. He was also seen as the highest of the pagan gods, and bore a great deal of resemblance to the Germanic god Thor. The Finnish word for thunderstorm (ukkonen) is derived from his name, and with good reason: thunderstorms were definitely his thing. He carried a hammer, (or an axe, but I think the hammer’s cooler) and used it to control lightning.
Most all of the stories involving Ukko have someone beg a weather-miracle of him, and him answering the call with a big ol’ lightning bolt or storm. When Ukko got together with his wife Akka, their… union… created one of the most violent thunderstorms of all time. Aww yeah, Ukko.
Ukko bears a great deal of resemblance to neighbouring sky deities. As mentioned above, he is very Thor-like, with the wisdom and authority of Odin mixed in. There’s also a great deal of similarity with Zeus and Horus, and with the Baltic deity Perun. Finnish mythology is often manifested as a fairly even blend of Baltic and Germanic myth.