PHILADELPHIA (AP) — Arctic air plunged parts of the U.S. East Coast into deep freezes and broke records from Washington to New York on Friday.

The cold snap followed snow and ice storms earlier in the week, and weather forecasters warned that more sleet and freezing rain will be possible in the coming days.

Residents had to deal with more school cancellations, power outages, road hazards and water main breaks.

The deep freeze transformed Niagara Falls in northern New York state into an icy spectacle, encasing the trees around it into crystal shells and drawing tourists.

The Niagara River is flowing below the ice cover, so the falls aren't completely frozen.

But days of extreme cold have created a thick coating of ice and snow on every surface near the falls, including railings, trees and boulders

The National Weather Service said the low Friday got down to 6 degrees Fahrenheit (14 Celsius) at Reagan National Airport, just across the Potomac River from Washington. That beats the record low of 8 degrees Fahrenheit (-13 Celsius), set in 1896.

At Baltimore's airport, the temperature dipped down to 2 degrees Fahrenheit (17 Celsius). The record was 4 degrees Fahrenheit (15 Celsius), set in 1979.

In New York City's Central Park, the temperature hit a record 2 degrees Fahrenheit (-16 Celsius) (-17 Celsius), beating the previous low of 7 degrees Fahrenheit (-14 Celsius) in 1950.

A Boston-bound commuter ferry carrying more than 100 passengers had trouble steering in the ice and had to be towed to port. Ferry service was canceled elsewhere in the Northeast.

In western Pennsylvania, temperatures dipped to minus -18 degrees Fahrenheit (-28 Celsius) in some areas.