Thumping in front end of 2004 Saturn Vue

We have a 2004 Saturn Vue which developed a sudden thumping noise in the front-end last night. The thump is apparent as soon as we drive and increases in tempo in direct relationship with speed. We don’t see anything stuck in the tires or in the wheel wells. Any suggestions on what to look at?

Well, turned out to be a big lag screw in one of the tires. I looked them over twice, once before driving it and once after and never saw it.