bypass St Louis
 

On my attempt to make the iron butt, I will be leaving Milwaukee about noon on Tuesday and plan to be West of Oklahoma City by Wednseday. This puts me in Saint Louis about 6:00 PM. I plan to use I 55 to I 70 to I 270 to I 44. Am I going to run into traffic or construction on any of these routes at this time?

If you cross the river in downtown St. Louis (Poplar Street Bridge), you won't need I-270. You can get to I-44 West from I-55 South. If you bypass St. Louis and cross the river north of the city (Chain of Rocks bridge), then you will take the route you mentioned. At 6PM the traffic congestion will be in the opposite direction when you hit the city. I-44 can get pretty busy until you get past about Eureka. But it doesn't have any stop 'n go unless there is an accident.

Or you could take I-55 South to I-255 South and cross the river south (Jefferson Barracks Bridge) of the city. I-255 changes to I-270 which will then take you to I-44 West.

Good luck!

I just re-read your post and realized you are probably on your way.

Hope it goes well for you. Beware of the storms coming up I-44.

Will there be traffic on the most heavily traveled corridors at 6PM on a weekday? That's a good one.

Thanks Bezerko,

I'm leaving monday morning. I think you suggestion of I 55 to I 255 might be the best. I would guess any holiday traffic would be east bound from the west side of the city and not be in my way. Correct?

I'd do I-55 to I-255 to I-270N to I-44. A lot less traffic than you'll find on I-270 around the north side.
You're going to hit construction and lane restrictions on I-55 about milepost 30. I was thru there today and traffic was backed a little bit but moving slowly. However, I was thru there last week and sat dead still in traffic in a 5 mile backup. Took about 35 minutes to get thru the construction zone once traffic was moving.
You'll hit another construction zone on I-255 in the area of I-64 (E St Louis to Cahokia area). They have some lane shifts. Traffic has been moving OK thru there but it's slow most of the time.
Speed limit is reduced to 55 MPH and 45 MPH in places in construction zones. Don't try speeding thru those reduced areas. They're usually heavily patrolled. Fines are steep. The photo camera van has been posted in both zones. Also several squads.
Have a safe trip.

And that's the FAST way.

You might find this site useful: http://www.gatewayguide.com/