Updated March 15, 2023 at 12:58 AM ET

Northeastern states are being pummeled by an intensifying storm that is dropping several several feet of snow in some places and left roughly a quarter of a million customers without power by Tuesday evening.

The storms in the Northeast are part of weather systems affecting both U.S. coasts. In California, heavy rains intensified on Tuesday and left more than a quarter of a million customers without power in that state, according to poweroutage.us.

Forecasters said the first nor'easter of the season is expected to last through Wednesday morning. In the meantime, millions of people across the region are under winter alerts.

As of 6 p.m. ET, the National Weather Service warned that while the rate of snowfall that has been battering the area during the past 24 hours is expected to slow from 2 to 3 inches to about 1-inch per hour, the combination of "strong winds and the heavy-wet nature of the snow that has fallen, will result in further power outages and tree damage."

New York and New England can expect an additional snowfall between 3 to 8 inches overnight, the NWS added.

Power outages reached a high of about 270,000 households in New York, Massachusetts, New Hampshire, Vermont, Maine, Connecticut and Pennsylvania on Tuesday afternoon according to PowerOutage.US, and companies appear to be struggling to restore services. Shortly before 10 p.m. 232,510 households remained in the dark.

Five towns — Marlboro, Vt., Colrain, Mass., Moriah, N.Y., Stony Creek, N.Y., and Palenville, N.Y. — each had accumulated 3 feet of snow by Tuesday night.

Shortly before 11 a.m. ET, Windsor, Mass., reported 28 inches of snow, according to the National Weather Service office in Albany, N.Y.

By 1:3o p.m. ET, a total of nearly 250,000 electricity customers

"Snowfall totals 12 inches or higher are forecast over large portions of New England and Upstate New York," the National Weather Service says, adding that 24-30 inches of snow are possible in some areas.

The winter storm's effects are being made worse by 55-mph wind gusts, coastal flooding and the wet, dense snow it's bringing, forecasters say.

Snow is piling up in the Northeast

"The storm may even be too much of a good thing for skiers," NPR's Tovia Smith reports. "Mount Snow in Vermont got nearly 2 feet, but wind is blowing it around, and keeping some chair lifts from operating."

Precipitation has grown intense since it started arriving late Monday. By early Tuesday, many areas were seeing rain transitioning into snow, creating slippery, treacherous road conditions.

More than a foot of snow was reported in New Hampshire's Hillsborough County, with 16 inches measured near Francestown, according to the NWS office in Portland, Maine.

Wilson Ring / AP

/

AP

Through Tuesday night, the NWS says, snow is expected to fall at rates of 2 to 3 inches or more each hour, driven by strong winds.

In Massachusetts, the state lowered the speed limit to 40 mph on a stretch of Interstate 90, as it deployed more than 900 pieces of equipment to clear snow and ice.

States warn of a long-lasting storm and disruptions

Heavy snow could bring "significant power outages" that last for days, reports Maine Public Radio, citing John Palmer of the National Weather Service office in Gray.

"It's going to be very easy for these tree limbs to fall down from the amount of weight, and then also the strong winds," Palmer said.

People who might be affected by power and water outages should take precautions such as filling bathtubs to provide water for flushing toilets and filling containers with drinking water, reports Connecticut Public Radio. People should also make sure to have batteries, candles and matches on hand, along with flashlights and a radio.

New York is under a state of emergency, as Gov. Kathy Hochul ordered emergency teams into place ahead of the storm. She also activated the National Guard to help with aid and recovery, warning New Yorkers of "a significant and long-duration Nor'easter."

In Syracuse, a Delta jet that was attempting to take off from Syracuse Hancock International Airport around 7:30 a.m. ET for a flight to La Guardia instead "exited" the taxiway, winding up on the unpaved ground, member station WRVO reports. The plane's 61 passengers and their luggage were ferried back to the terminal. The airport remains open, but a dozen flights have been canceled.

/ NOAA/NESDIS/STAR

/

NOAA/NESDIS/STAR

What's a nor'easter?

It's basically what happens when two fire hoses — the polar jet stream, and the Gulf Stream — hit each other, splattering the Northeast coast with snow, rain and wind.

"During winter, the polar jet stream transports cold Arctic air southward" into the central U.S., and then toward the Atlantic Ocean, the NWS says. But another force is directing energy toward that same area, as the Gulf Stream flows northward along the coast, warming the air and keeping water temperatures relatively mild.

"This difference in temperature between the warm air over the water and cold Arctic air over the land is the fuel that feeds Nor'easters," according to the NWS, which says the storms often first develop "between Georgia and New Jersey, within 100 miles east or west of the East Coast." They grow to "maximum intensity" as they approach New England.

In the current storm, a surface low-pressure system that had been off the North Carolina coast rapidly intensified Monday night into early Tuesday, as it pushed northward into southeast New England.

A or'easter can happen anytime between September and April. Some of the worst storms have struck in March, from the Ash Wednesday storm of March 1962 to the March 1993 "Storm of the Century." They've caused billions of dollars in damages and dozens of deaths.

Copyright 2023 NPR. To see more, visit https://www.npr.org.