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Snowtober: Rare Halloween Snow to Hit East Coast

The encroaching snowtober storm. This image was taken by GOES East at 1615Z on October 28, 2011. (Image credit: NASA/NOAA.)

If you live in the northeastern U.S., this Halloween will not be a good year to dress in a skimpy costume that begins with the word "sexy."

A low-pressure system is moving up the East Coast tonight (Oct. 28) and could bring between 4 to 8 inches (10 to 20 centimeters) of snow from the higher elevations of Virginia and West Virginia northeastward through eastern Pennsylvania, according to the National Weather Service. A band of 8 to 10 inches (20 to 25 cm) is possible from extreme northern Maryland northeastward through northern New Jersey and into western Massachusetts.

A "slushy coating" of 1 to 2 inches (2.5 to 5 cm) is expected for the big northeastern cities, according to Bob Smerbeck, senior meteorologist from AccuWeather.com. [The Snowiest Places on Earth ]

This early winter chill is about as unusual as getting an apple while trick-or-treating.

"It's definitely rare for the big cities to get accumulating snow for October," Smerbeck told OurAmazingPlanet.

Any measurable snow in the big northeastern cities would be about a month early, according to the Weather Channel.

In New York City, where up to 1 inch (2.5 cm) of snow is expected over the weekend, snow has fallen in October just three times since 1869, according to the Wall Street Journal. If even 1 inch of snow falls in New York City, it would set a monthly record for October.

Boston does not see much snow in October either; snow has fallen in the city during October only four times in city records (twice in the past decade). As little as 1.2 inches (3 cm) of snow would set a monthly record there.

In Philadelphia, 2.2 inches (5.6 cm) of snow would set a new October record. Philly has had measurable snow in October three times.

"All of these records have a potential to go down with this storm center," Smerbeck said.

Some 25 million people are under a winter storm watch this weekend, and power outages are possible if the heavy, wet snow piles up on tree limbs still supporting their colorful leaves, sending them crashing into power lines.

On the other side of the country, Denver saw another October snow oddity this week. The city went from a record daily high of 80 Fahrenheit (27 degrees Celsius) to several inches of snow in 24 hours.

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You can follow OurAmazingPlanet staff writer Brett Israel on Twitter: @btisrael. Follow OurAmazingPlanet for the latest in Earth science and exploration news on Twitter @OAPlanet and on Facebook.

Brett Israel was a staff writer for Live Science with a focus on environmental issues. He holds a bachelor’s degree in biochemistry and molecular biology from The University of Georgia, a master’s degree in journalism from New York University, and has studied doctorate-level biochemistry at Emory University.