CHICAGO (Reuters) - At least 22 deaths have been blamed thus far on the heat wave that for weeks has been taking its toll on the central United States and on Wednesday was expanding eastward, according to the National Weather Service.
Hospitals in Wichita, Kansas, treated 25 heat-related illnesses, according to the Weather Service report. In Des Moines, Iowa, 16 people were hospitalized because of the heat.
In Minneapolis dozens of fans at recent Minnesota Twin games have been treated for heat issues, even though the club did take extra precautions such as providing free water stations and having first aid and guest service staff on hand to monitor crowds.
Day after day of high temperatures and humidity with no relief overnight was taxing the region.
"It's just draining, physically draining," said Chris Vaccaro, a Weather Service spokesman.
At least 27 states were under some sort of heat warning, watch or advisory. In Philadelphia on Wednesday temperatures were forecast to reach 93 degrees. Raleigh, North Carolina, could see 99 degrees, and it could be 95 degrees in Washington, D.C.
At 11:30 local time, it was already 91 degrees in the shade outside the Chicago Board of Trade Building in the Loop.
"It's hot today, but it's going to be hotter later in the week" on the East Coast, said Jim Keeney, a meteorologist with the Weather Service.
In Pittsburgh, some residents said they had plans to stay cool as temperatures rose.
Retired police records clerk MaryAnn Dean was heeding the experts' advice to stay indoors.
"I'm not one that likes the real hot humidity," said Dean, 59. "I'm just staying in the air conditioning."
TO THE POOL TO COOL
Meredith Brown planned to head to the pool with her dog to escape the heat.
"My dog is kind of going a little crazy with it," said Brown, 29, as she walked her pooch. "It's a little hard for him."
The high heat and humidity was stressing U.S. crops, particularly corn, which is in a key production phase.
An atmospheric high pressure ridge hanging over the Midwest was blocking moisture from moving into the crop belt, as well as causing a buildup of heat, said agricultural meteorologist John Dee of Global Weather Monitoring.
The ridge will weaken by the weekend, permitting cooler temperatures and some rainfall in the Midwest.
"It's still hot and humid and it will stay that way this week, a little cooler by the weekend and a few showers can be expected then," predicted Dee.
Corn and soybean crops need more rain to boost production prospects.
Traders at the Chicago grain and livestock futures market exchange said the drought and heat in the Plains was beginning to cause concern about the fate of next year's output of the primary grain used for bread, the hard red winter wheat crop grown in a wide swath from Texas to South Dakota.
Farmers plant that crop in the fall and harvest the following summer. If rains did not come soon, farmers may not plant wheat because of the powdery dry soil.
The prolonged excessive heat was also endangering livestock. Up to 1,500 cattle have died in South Dakota because of the heat wave, according to the state's veterinarian, Dustin Oedekoven, and he expected that number to rise.
"The weather is certainly extraordinary," Oedekoven said.
The high heat and humidity with little relief overnight has made it "a challenge to keep livestock comfortable."
The Nebraska state veterinarian's office also reported a significant number of cattle deaths.
In east Tennessee, early morning storms led to some flash flooding already and Weather Service meteorologist Trevor Boucher said there could be more flooding to come.
"The entire area has a slight chance for storms and the biggest danger is heavy downpours," which he said could lead to more flash floods.
If there were a small silver lining in this massive, oppressive heat wave, it was that a cold front currently moving across Montana was forecast to drop temperatures across the upper Midwest later Wednesday and into Thursday.
"It's starting to break down somewhat," said Keeney. "Even if it does, it's still going to be hot."
(Additional reporting by Sam Nelson, Bob Burgdorfer, Meredith Davis, Tim Ghianni, Kevin Murphy, Daniel Lovering and James B. Kelleher; Editing by Jerry Norton)