The dip in power Wednesday morning was brief, but it was enough to halt MTA trains for five minutes, causing delays on the entire subway system.

Con Edison said the day's temperatures -- in the 80s at the time before creeping into the 90s -- were not to blame for the power outage that briefly knocked out the subway's signal system shortly after 9:30 a.m. Damaged equipment at Con Edison's Lower East Side substation caused power transmission cables to fail and "they essentially took themselves out of service," explained Con Ed spokesman Allan Drury.

"We're not close to the heat that we'll see later on in the summer," Drury said. "We're not close to the amount of electricity usage we'll see in the summer."