Jack finds himself stuck on I-70 in the middle of Kansas when traffic is completely stagnant. He was trying to get to his parents in northern Missouri. He decides he must leave the road to have any hope of getting to Missouri.
Before leaving the interstate he cannibalizes an old car for parts to prepare for the journey.
He now leaves the interstate and starts driving through fields of dying crops.
After traveling for a day he finds a farm and trades his watch and repairs a tractor for diesel fuel.
In Kansas City Jack finds an abandoned ambulance and uses the air masks to make a new air filter for his Jeep.
After traveling all night he finally makes it to his parent's farm near Macon, Missouri.