Weather Service on high temperatures: 'Do not take this threat lightly'

Crowds flocked to waterfronts and swimming pools on the East Coast and in the Midwest on Thursday to try to cope with a massive heat wave that has killed at least 22 people this week.

The National Weather Service issued excessive heat warnings for wide areas of the central and eastern United States, saying the combined heat and humidity could push the "real feel" temperature to 115 Fahrenheit (46 Celsius) through Saturday.

By Thursday afternoon in New York City, the thermometer hit 91 degrees (33C) but it felt more like 112 degrees (44C), according to AccuWeather.com.
With the promise of refreshing ocean breezes, Boston's whale-watching ships and high-speed tourist boats sold out their trips by mid-morning.
Dangerous heat wave blankets much of US (on this page)

Cooling centers in Richmond, Virginia, and New York City welcomed overheated residents and a truck labeled "Water Fountain on the Go" cruised Manhattan streets, offering to refill water bottles to keep residents hydrated.

Electricity utility Con Edison said scattered outages were likely in New York in coming days with demand expected to hit all-time highs.

Unhealthy smog levels triggered by the heat were reported in Chicago, where residents were asked by the Illinois Environmental Protection Agency to reduce polluting activities such as idling vehicles and mowing lawns.

By the weekend, the heat wave is expected to cover half of the United States and affect nearly half of its 310 million people, AccuWeather.com forecaster Mary Yoon said.

"What makes this heat wave so impressive is the pure size and longevity," said Yoon.

"Through the rest of this week and into the weekend at least 15 states starting from the Southern Plains and Midwest and much of the Northeast will witness 90 degree-plus temperatures with high humidity."

Kevin Roth, the lead meteorologist at the Weather Channel, said early Thursday that the "dangerously high temperatures and humidity levels" would continue in Kansas to the Lower Great Lakes, with heat indices soaring as high as 120 degrees.

But a cold front would temporarily bring a measure of relief to the northern Plains, Upper Midwest and northern Great Lakes, Roth said.

Temperatures in those areas should be in the 80s on Thursday before rising again on Friday and Saturday, Roth said.

By late Thursday morning, the heat index at Philadelphia International Airport had already reached 100.2, more oppressive than conditions in Miami, where the index was 98, philly.com reported.

Long-standing record highs in Philadelphia and several other major cities may melt away by Friday, when the mercury was expected to spike, according to meteorologist Meghan Evans of AccuWeather.com.

"Do not take this threat lightly," the weather service warned in a statement on its website, noting the extreme temperatures are particularly dangerous for the elderly and the very young.
"The length of this heat wave will pose a very real and dangerous health risk to these at-risk groups and those that do not have access to air conditioning."
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Early morning commuters waiting for New York City subways at 7:30 a.m. were drenched through their clothing with perspiration and those rushing along city sidewalks pressed iced coffee cups to their foreheads as they headed for air-conditioned offices.

The low pressure system that barreled east was expected to bring powerful thunderstorms with hail to New England, forecasters said.

In the central United States, where the high temperatures have killed nearly two dozen already, another death was tied to the heat on Wednesday.

An elderly woman whose body was found in her bedroom in St. Louis, where a working air conditioner had not been turned on despite 99 degree temperatures, was determined to have died of heat stroke.
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The cumulative effects in terms of lost lives, stress on the power grid and damage to roads and bridges could eclipse the effects of the deadly heat wave of 1995, which claimed hundreds of lives in Chicago alone, AccuWeather.com predicted.

"When all is said and done, with the number of days of extreme heat and humidity of the current heat wave, it may be more significant and impact a larger area," said AccuWeather's Jim Andrews.
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Hospitals in Wichita, Kan., treated 25 heat-related illnesses, according to the National Weather Service.

In Des Moines, Iowa, 16 people have been hospitalized because of this week's high temperatures.

The high heat and humidity have been stressing U.S. crops, particularly corn, which is now in a key growth stage, and 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 expects that number to rise.

In Indianapolis, homeowners were being asked to stop watering their lawns through at least Sunday.
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