Vibration in Steering (first 5 minutes)

[drburton]

I have noticed that when I initially take the car out and drive it (especially on highway) there is alot of vibration in the steering wheel. However, after 5 or so minutes of driving it goes away.

Since my car is not a daily driver, could this just be the tires warming up (flat spots maybe). Just wondering if anyone else experiences this or if I should be worried about a balancing or alignment issue.