The final section of the Intercounty Connector will be open by 6 a.m. Nov. 22, according to Jack Cahalan, a spokesman for the Maryland Department of Transportation.
Previously, the state had not said exactly when the section would open.
"The weather has played in our favor," Cahalan said.
Construction on the toll road, which cost $2.6 billion, started in 2007.
The ICC is currently open from Route 97 (Georgia Avenue) through Interstate 370, which feeds into Interstate 270, the main artery between Frederick and Washington.
When complete, the ICC will run about 18 miles, and link Interstate 95 in Prince George's County with the I-270 corridor in Montgomery County.