4-US Northeast-Midwest grids near record power demand

NEW YORK, Aug 3 (Reuters) - Demand for electricity in the U.S. Mid-Atlantic and Midwest climbed to near record levels but did not exceed the all-time peaks set during an intense heat wave last week, power grid operators in the region said on Wednesday.

Despite widespread heat and humidity, grid operators said their systems held up well and no emergency conservation measures were needed to meet the surge in demand.

PJM Interconnection, which operates the biggest U.S. power grid serving more than 51 million people in parts of 13 Mid-Atlantic and Midwest states, said demand late Wednesday was running near 135,000 megawatts, or close to the grid's all-time high of 135,000 MW set last week on July 26.

"It's going to be close (to a record). We're expecting to come in right around 135,000 megawatts. Everything went fairly well throughout the day," said PJM spokeswoman Melissa Schwenk, adding PJM was expecting similar hot conditions on Thursday.

High temperatures from Chicago to New York reached into the mid-90s Fahrenheit on Wednesday, with the humidity making it feel like more than 100 degrees.

But while New York was forecast to see another 90-plus day on Thursday, readings in Chicago were expected to slip back into the high-80s.

The New York ISO, which operates the state grid for more than 19 million people, said consumers did not use a record-breaking amount of energy on Wednesday but would probably set a new peak on Thursday.

"We did not break the record today - the humidity was not quite what they expected - but we will tomorrow," said Carol Murphy, spokeswoman for the New York ISO.

Murphy said power demand Wednesday peaked at 31,750 MW, shy of the all-time high of 32,075 MW set last week on July 26.

But she said the New York ISO was forecasting record demand of 32,600 MW on Thursday.