Why does a nor'easter turn into such a monster storm?

Hook

Why and how does a nor'easter turn into such a monster storm? Every winter, these storms slam the East Coast with heavy snow, howling wind and flooding. And one is hitting the Northeast this week.

Name

A nor'easter gets its name from the wind. As the storm moves up the coast, the winds hitting the shore usually blow in from the northeast.

Ingredients

It needs two ingredients that meet along the East Coast. Cold, dry air pouring down from Canada, and warm, moist air sitting over the Atlantic Ocean, near the Gulf Stream.

Low

Where that cold air and warm air collide, a low pressure system can form and deepen. Air rushes in toward the center, rises, cools, and its moisture falls out as rain or snow.

Bomb

Some nor'easters strengthen incredibly fast. When the central pressure crashes about eighteen to twenty four millibars in a single day, depending on how far north it is, meteorologists call it a bomb cyclone.

Track

The track decides who gets what. Just inland of the storm's center, it's often cold enough for heavy snow. Closer to the coast, warmer ocean air can turn it into rain or a messy mix.

Season

They can happen any time of year, but they're most common and most powerful between September and April, when the temperature difference between land and ocean is biggest.

Close

So a nor'easter is what happens when Arctic air and warm ocean air collide off the East Coast and spin up a powerful storm. ThatsWhyHow.