By Chris Michaud and Daniel Trotta

NEW YORK (Reuters) – Forecasters put the U.S. East Coast from New York City to Boston on a blizzard watch starting as early as Monday night, with authorities warning residents to prepare for the possibility of widespread power outages, road closures and flight disruptions.

Weather experts predicted the region could see 12 to 18 inches of wind-blasted snow from Monday to early Wednesday.

New York Governor Andrew Cuomo announced preparations for the so-called Nor’easter storm, activating the state Emergency Operations Center as of Monday night while also directing state agencies to be on heightened alert.

“I encourage all New Yorkers in affected regions to plan ahead and avoid any unnecessary travel as the storm progresses,” Cuomo said in a statement, adding that commuters should expect road closures, delays and cancellations.

The storm also raised the potential for power outages with damaging winds across eastern Long Island and southeastern Connecticut, the National Weather Service said.

Significant disruption to air travel in the region was also anticipated with the storm.

Blowing snow and strong winds could lead to whiteout conditions with visibility as poor as a quarter mile, the service said. Sub-freezing temperatures were forecast in the upper 20s Fahrenheit.

New York City issued a snow alert for Monday night into Tuesday, expecting snowfall rates of up to 2 to 4 inches per hour Tuesday morning and afternoon, with gusts of up to 50 mph.

Mayor Bill de Blasio warned New Yorkers that “besides the snow, it will be cold,” while officials recommended that people avoid driving and use mass transit when possible.

The Port Authority of New York and New Jersey was installing hundreds of pieces of snow equipment at the three New York area airports. Thousands of tons of salt and sand were prepared for airport roads, parking lots, bridges and tunnels.

As some 50 million people along the Eastern Seaboard came under storm or blizzard watches, Washington, D.C., which often bogs down with even low levels of snow, was expecting 5 inches and twice that in outlying areas.

The storm comes near the end of an unusually mild winter along much of the East Coast, with below-normal snowfalls in some areas, including New York City and Washington. It was the warmest February on record in nearly the entire area, according to the Northeast Regional Climate Center.

Last week in New York, temperatures hovered near 70 degrees Fahrenheit, according to Accuweather.com, hitting 60 or higher on six days in February.

Meanwhile, in the western United States, the weather service forecast potentially record-setting heat in Arizona, Colorado, New Mexico and Utah, where temperatures were expected into the 90s in some places.

(Reporting by Chris Michaud and Daniel Trotta; Editing by Randy Fabi)