The central and southern Tennessee Valley is now experiencing "exceptional drought" conditions, according to the U.S. Drought Monitor.

According to the drought monitor, 99 percent of Tennessee is in severe drought. About 13.6 percent of the state is in exceptional drought, the highest category of the drought monitor. That includes part of Knox and 15 other East Tennessee counties. Parts of Sevier, Roane and Cumberland counties and all of Loudon, Blount and Monroe counties are also in the exceptional drought category.

Part of East Tennessee is experiencing 'exceptional' drought conditions. Nov. 25, 2016. 
Part of East Tennessee is experiencing 'exceptional' drought conditions. Nov. 25, 2016. 

Knoxville has received only about a quarter of an inch of rain in November, and is now running a rainfall deficit of nearly 10 inches for the year.

The good news is scattered showers should arrive late Monday night and last through Tuesday and Wednesday. Heavy rain will be possible at times, with totals as high as two to four inches.

The dry conditions have made firefighters' jobs more difficult this fall, as they continue to work against dozens of wildfires across the state and the Southeast. The Tennessee Department of Agriculture Division of Forestry is fighting 66 fires for a total of 25,892 acres across the state as of Friday.

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Parts of Alabama and Georgia are also in exceptional drought, as well as a few counties in northern Mississippi and the western tips of North Carolina and South Carolina.