Heat 'Dome' Trapping Vast Parts of the U.S. Sets Sights on East Coast

July 20, 2011 — -- This week, the East Coast is expected to get a taste of what life has been like for the Midwest and Gulf Coast for days and even weeks, but the heat wave that has killed as many as 22 people isn't exactly moving on -- it's just growing larger.

Nearly 200 million sweltered in dangerously high temperatures today. There are heat warnings and advisories in 36 states, and temperatures in many areas have broken the 100-degree mark.

The National Weather Service said the extreme weather had killed as many as 22 people, and attributed it to a heat "dome" sitting over much of the nation. The "dome" is caused by a huge area of high pressure that traps and compresses hot, humid air from the Gulf of Mexico.

Hot, Hot, Hot: Send Us Your Heat Wave Photos

In Indiana, farmers in the central part of the state were trying to cope with the scorching sun.

"It's hard on the plants that are fairly young," said Carol Waterman of Waterman Farms, which grows produce in Indianapolis. "If this continues, the plants that are setting blossoms will abort those blossoms because when they are under stress, the first thing they give up is that fruit."

The heat wave has set more than 200 records since Friday. In Chicago, temperatures were in the high 90s today, although it felt like 105 or hotter.

To make matters worse, some area residents had to cope with no air-conditioning because of a power outage.

In Minnesota, the heat index hit 134 degrees Tuesday. In Iowa, blistering heat buckled highways. And in South Carolina, residents prepared for a second major heat wave as the National Weather Service issued a heat advisory today.

Schools in Tennessee, where a heat advisory is in effect for the western half of the state, rescheduled practices and scrimmages for their student-athletes as weathercasters predicted heat indexes of 110.

As some major U.S. cities prepared to keep public swimming pools open longer to help residents beat the heat, in Detroit, where temperatures rose into the 90s, county officials discussed closing the city's only water park because of budget cuts. Thirteen public schools in Detroit were opened as cooling stations.

For those in the Midwest hoping to take a dip in a lake or pond, the severe heat has also helped a dangerous algae to thrive, threatening swimmers and livestock. Blue-green algae can cause skin irritations and even damage the liver and central nervous system.

"Anything that has a scum to it and a pea soup look, that's what you want to stay out of," said Ross Adkins, a spokesman for the U.S. Army Corps of Engineers in Tulsa, Okla. "Usually, it's just the stagnant areas where you'll find it. If you've got moving water, you don't usually find it."

Ways to Beat the Heat

The National Weather Service has safety tips for adults looking to keep cool.

The Associated Press and ABC News Indiana affiliate WRTV-TV and Chicago affiliate WLS-TV contributed to this story.</>