I remember it's pretty long, it doesn't have lyrics and it's very popular.
It has nice piano melody that becomes more saturated in the middle of track. It also has strong techno beats and thunder sounds in it.
Ok, with the techno info i take a guess, is it maybe "Children" from Robert Miles?
You have a thunder-like sound in there, the Piano sound, and it has a techno beat but no lyrics. In the late 90s it was very popular but it is only 4 minutes long. There are some different versions of this song (dream version is 7:33 long, but has no thunder sound), this is a link to the classic one:
Maybe I'm wrong but I think you're talking about the Telegraph Road (Dire Straits). It's about 14min long, it begins with thunder and there is piano in it. There are lyrics (Mark Knopfler), but very few.
Best song ever!