Via Angry Bear, there’s interesting current and historical information at Drought Monitor.
For example, on the main page there’s a United States map showing the current drought areas. Most of the Tennessee Valley is in a D4 “Exceptional” Drought on the October 23 map. The site also has six-week and twelve-week animations. East Tennessee has been in a D3 or D4 drought throughout those periods.
Drought Monitor also has historical maps of the Palmer Drought Index going back to 1895. According to this map, Tennessee experienced severe or extreme droughts 5% – 10% of the time from 1895 -1995. The drought periods in the Tennessee River basin are charted here.
