The numbers on the signs
are all getting smaller
burning in our headlights
on this harsh and hazy highway.
The cornstalks in the fields
are all getting taller;
hope hovers in their shadows
as we brave this broken byway.
The odometer says we’ve got
a thousand miles to go
and we pray there will be shelter
when we finally arrive.
Our hearts are harried, worn
and our tanks are running low;
is there somewhere else to go?
We ponder, as we drive.
Whimsygizmo's Blog 
I don’t often rhyme, in the traditional sense, but the pacing of this felt right…like watching those yellow dashes fly under the car while driving…
Written for Poetic Bloomings (head over and write your own “on the road” poem!):
http://poeticbloomings.com/2012/02/26/where-the-rubber-meets-the-road-prompt-44/
I like the feel of this and your comment about the yellow dashes, too!