It is always wise to steer clear of speculation and stick with the parameters God has set for our understanding via His revelation.  He does not tell us everything, a point sadly missed by too many (see Deut. 29:29; Isa. 55:8,9; I Cor. 13:12).

A helpful perspective can be found here:

http://www.samstorms.com/enjoying-god-blog/post/tornadoes–tsunamis–and-the-mystery-of-suffering-and-sovereignty