PADUCAH, Ky. (AP) - Heat and humidity are again building in Kentucky and the National Weather Service has issued an excessive heat warning for western counties in the commonwealth.
   
The warning is from 10 a.m. Monday through 7 p.m. Thursday. The time span and scope of the warning could be expanded later.
   
The NWS office in Paducah said heat indexes are expected to reach about 105 degrees. That's the combined effect of heat and humidity. There won't be much cooling at night, with minimum indexes forecast in the mid-70s.
   
Forecasters caution that the effect on people and animals is cumulative and the warning was issued partly because of sustained hot weather in the region.
   
The warned area includes western Kentucky and extends as far east as Owensboro, Madisonville and Hopkinsville.

Forecasters have issued a heat advisory for much of West Tennessee as heat and humidity build.
   
The National Weather Service said heat indexes are expected to reach dangerous levels Tuesday and Wednesday. The effect of heat and humidity combined is expected to reach 103 degrees to 109 degrees between 11 a.m. and 7 p.m. both days. High temperatures around 97 degrees are forecast. Overnight lows in the mid- to upper 70s will provide little relief.
   
The advisory initially covers the counties of Lake, Obion, Weakley, Dyer, Gibson, Lauderdale, Tipton, Haywood, Crockett and Shelby. The NWS says it might expand the advisory later.

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