June 9 (Bloomberg) -- The first U.S. heat wave of the year is searing states from Georgia to New York with record temperatures of about 100 degrees Fahrenheit or more, and there's no relief in sight until mid-week.

Temperatures in New York soared to the upper 90 degrees Fahrenheit (32 Celsius), while humidity pushed heat indexes as high as 104 degrees, the Accuweather.com forecaster said. The four-day heat wave is expected to subside late tomorrow.

``To get a stretch of four to five days with temperatures in the 90s at this time of year is unusual,'' Accuweather.com senior meteorologist Tom Kines said in an interview from the firm's State College, Pennsylvania, headquarters. Severe heat in August 2006 in New York killed 46 people and disrupted power supplies.

Relief will come from a cold front moving across the Great Lakes region today that will head to the Northeast tomorrow night, lowering humidity, Kines said.

In the Midwest, rainstorms drenched Indiana, Iowa, Illinois and Wisconsin as well as Kansas and Oklahoma. President George W. Bush declared Indiana a flood disaster area late yesterday after more than 10 inches (25 centimeters) fell in two days. The storms killed at least eight people in the Midwest at the weekend, weather agencies said.

In Wisconsin, Governor Jim Doyle declared an emergency for 29 counties because of flooding and severe storms. The state activated National Guard soldiers to assist as the storms damaged homes and businesses, washed out roads and collapsed power lines.

Richmond Roasts

Today's temperatures will reach almost 100 degrees in Washington, and may hit 104 in Richmond, Virginia, breaking a 1999 record of 98 for the same day, Accuweather.com said. Yesterday's high of 94 in Providence, Rhode Island, tied a 1984 record for that day, the National Weather Service said.

Heat is the leading weather-related killer, according to the National Weather Service. More than 1,500 people in the U.S., on average, die from excessive heat each year.

The New York advisory indicates the heat and humidity will feel like 100 degrees Fahrenheit or more. ``Cooling stations'' for people without air-conditioning have been opened in at least three centers in each of the city's five boroughs, said New York City Office of Emergency Management spokesman Chris Gilbride.

Electricity use in New York state reached 32,311 megawatts at 4 p.m., the highest since the record of 33,939 megawatts set Aug. 2, 2006, New York Independent System Operator, which manages the power market and high-voltage grid, said on its Web site.

``We'll be able to meet that load,'' Ken Klapp, a spokesman for the operator, said today in an interview.

PJM Interconnection LLC, which runs the electricity market for Washington, Philadelphia and New York's New Jersey suburbs, forecast adequate supply to meet cooling demand today, spokesman Ray Dotter said today in an e-mailed statement.

There probably won't be another four days of sustained heat in the next couple of weeks, Accuweather.com's Kines said.

To contact the reporter on this story: Robin Stringer in New York at rstringer@bloomberg.net; Joseph Galante in San Francisco at jgalante3@bloomberg.net

Last Updated: June 9, 2008 16:25 EDT