(Columbus) — The speed limit is increasing on parts of U.S. and state routes throughout Ohio this weekend.

The changes take effect Sunday on more than 600 miles of road in the state's second round of speed-limit increases this year.

The speed limits increase to 70 mph on rural freeways, 60 mph on rural divided highways and 65 mph on rural expressways that don't have traffic control signals.

A spokeswoman for the Ohio Department of Transportation says drivers should respect the current speed limits until new signs are posted.

The department says the changes require 1,100 new or replacement highway signs, which are expected to be installed by Friday.

Three months ago, Ohio raised the speed limit to 70 mph on some rural interstate highways.

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