From the National Weather Service:

Widespread heavy rainfall will accompany this system. Rainfall will develop early Thursday morning over northwestern Middle Tennessee, then spread across the remainder of the mid-state on Thursday and continue throughout the night.

During a 30-hour period from midnight Thursday morning until 6 a.m. Friday, a total of 1-2 inches will occur in areas to the east and south of Nashville, including Murfreesboro.

The heaviest rainfall is expected to occur across the Nashville Metro area and to the north and west of the city with a total of 2-4 inches expected.

As the ground becomes saturated during this event, the potential for flooding will increase.

Places most prone to flooding will include urban areas, low-lying areas, and places along creeks and streams.

Water levels on rivers may also rise significantly, and river flooding may also occur as excessive rain water drains off saturated areas.