Storms across the nation

(NBC) - Extreme weather continues to threaten much of the nation.

From tornados to flooding and deadly heat, thousands of people in several states are keeping a close eye on the forecast.

In Oklahoma City relentless rain saturated soil and flooded streets.

High water stranded motorists, forced road closures and prompted at least half a dozen rescues.

Heavy rains also pounded Indiana, flooding neighborhoods, while tornados threatened areas from Texas to Ohio.

Rains triggered flash flooding that shut down traffic, damaged businesses and forced evacuations overnight in Kansas City.

Meanwhile, water is receding at a southwest Arkansas campground where a 20th body has been recovered.

The number of missing had been downgraded from 40 to 20 after last week's devastating flood.

Searchers are now focusing on several debris piles left in the wake of the floodwaters.

Two rivers surrounding the campground rose 20 feet within hours, catching campers off guard.

Searchers will continue to comb the area, even though it's unclear if anyone is still missing.

In the south, it's stifling heat.

Extreme temperatures are blamed for a man's death at the huge Bonnaroo music festival in Tennessee.

A 29-year-old fan attending the event near Nashville was overcome by the heat.

Officials say his temperature rose to 108 degrees.

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