June 20 (Bloomberg) -- New York City is opening 455 cooling centers to provide respite from temperatures that may reach 98 degrees Fahrenheit (37 Celsius) today and feel closer to 108.
From Canada to the mid-Atlantic U.S., government agencies warned against oppressive heat that may increase electric use. The U.S. National Weather Service issued advisories that high temperatures and humidity may make outside activity dangerous through tomorrow. Environment Canada issued a similar warning for southern Quebec, including Montreal.
An excessive heat warning has also been issued for New York City and the metropolitan area including Newark, New Jersey, until 8 p.m. because hot weather and humidity may make it feel like temperatures are between 105 and 108.
“It’s going to be hot and it’s going to be humid, and we want to make sure people are taking all the appropriate precautions for that,” said Lauren Nash, a Weather Service meteorologist in Upton, New York.
New York City residents were urged to limit unnecessary electric use as much as possible while the heat persists, according to a statement from Consolidated Edison Co.
The high temperature in Central Park is expected to reach 98, according to the Weather Service. That would be the first time Central Park has seen 90 degrees or higher since last August, according to the Weather Service. The high reached 89 on May 28 and 29.
New York Mayor Michael Bloomberg ordered the 455 air-conditioned centers opened around the city through tomorrow. The mayor is the founder and majority owner of Bloomberg News parent Bloomberg LP.
“Prolonged heat can put you at risk for serious health consequences,” said city Health Commissioner Dr. Thomas Farley. “For anyone who is elderly or living with a chronic health condition like diabetes or mental illness, a series of hot days can lead to heat exhaustion, heat stroke, even death.”
Low temperatures in New York are forecast to be 78 overnight. Nighttime lows in the high 70s can make sleeping uncomfortable and boost air conditioning use.
The dew point, a measure of how much moisture is in the air, may also determine energy demand, said Tom Kines, a senior meteorologist at AccuWeather Inc. in State College, Pennsylvania.
“When the dew point gets up to 70 degrees, just about everybody is feeling uncomfortable, and when it gets up to 74, it’s miserable,” Kines said. “I suspect there will be locations where the dew point gets into the 70s.”
Today’s temperatures may reach 98 in Boston and Baltimore; 97 in Philadelphia and Washington; and 95 in Chicago.
An excessive heat warning was also issued for Philadelphia; Trenton, New Jersey; and the upper Hudson River valley including Poughkeepsie.
In Washington, residents should stay indoors as much as possible, drink plenty of liquids and never leave pets or children in parked vehicles, according to a statement released by the city.
Toronto may reach 95 today and Montreal 87, according to Environment Canada.
Nash said the worst of the heat is expected tomorrow, when New York may again see 98 degrees, and temperatures may remain in the 90s into the weekend before cooling begins.
Kines said a cold front is expected to start reaching the East Coast starting the day after tomorrow, breaking the heat. It will probably spark strong thunderstorms as it moves through.
While temperatures won’t fall drastically when the front passes, the humidity will decrease and conditions will be more comfortable, Kines said. After that, it may be a while before the East Coast has its next round of hot weather, he said.
New York’s temperature reached 90 or higher 20 times last year, with three of those days in June, according to the Weather Service. June has an average of 2.9 days of 90 degrees or higher in records going back to 1870.
The New York Independent System Operator, which oversees much of the state’s electricity grid, had its highest demand of 33,939 megawatts on Aug. 2, 2006, according to the ISO’s website. The grid operator expects a peak of 33,295 megawatts this summer.
Wholesale power in New York City rose to $860.34 a megawatt-hour at 11:10 a.m. today and Long Island rose to $917.35, according to the New York ISO. Western New York prices rose to $2,218.79. Spot prices for these areas were in the $20s at the same time yesterday.
New England spot power rose to a high today of $186.44 a megawatt-hour at 12:45 p.m. compared to the day-ahead price of $109.45, according to the region’s grid operator, ISO New England. Prices were in the $30s and $40s at the same time yesterday.
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