It's prime tornado season in North Carolina. Know what to do before a storm hits.

With the budding of the trees and the emergence of the first tender shoots of grass, spring seems like such a gentle season. But March to May in North Carolina are also tornado season, the months when the state sees the most of those violent, hard-to-predict storms that can bring churning winds of up to 300 mph.

Prime conditions for the formation of tornadoes are warm, humid air in the lower atmosphere and cooler air above, which occur more frequently in the spring in North Carolina than at other times of the year.

So far in the 2018 tornado season, the National Weather Service has issued only a couple of tornado watches for Eastern North Carolina because the weather has been relatively cool. Those went out in Wayne, Cumberland and Hoke counties on March 1, when a line of thunderstorms formed ahead of an advancing cold front.

Nick Petro, warning coordination meteorologist with the National Weather Service in Raleigh, said a funnel cloud that developed in southern Wayne County that day generated a lot of photographs.

“But not all funnel clouds reach the ground, and luckily, that day, that one didn’t,” Petro said.

Many others have.

Weather service data indicate at least 1,270 tornadoes hit North Carolina from 1950 to 2016, causing at least 140 fatalities. Many have occurred as part of tornado “outbreaks,” in which numerous storms form simultaneously or within a short time of one another. One of the worst of those occurred from April 14-16, 2011, when dozens of tornadoes formed in the mid-Atlantic states.

North Carolina was the hardest hit, with 30 storms hitting the state on April 16, including one that struck downtown Raleigh.

The storms had been well forecast, and still, two dozen people were killed and more than 300 others injured across the state that day, the worse one-day tornado total in North Carolina history according to the weather service. All the fatalities occurred within the boundaries of tornado watches and were preceded by tornado warnings.

One tornado that day came within 1.75 miles of the weather service’s third-story Raleigh office, prompting staff to evacuate.

N.C. Emergency Management offers tips on its ReadyNC website on how to prepare for tornadoes, because once a storm has formed, those in its path usually have less than 30 minutes to respond.

What to look for

• Know the terms: a tornado watch means conditions are right for tornadoes to form. A tornado warning means a tornado has actually been sighted.
• Tornadoes occur near the trailing edge of a thunderstorm. It is not uncommon to see clear skies behind a tornado. Before a tornado, skies may appear dark and often greenish.
• If a watch or warning has been posted, falling hail is a danger sign.
• Before a tornado hits, the wind may quiet and the air become still.

Where to go

If you see these danger signs above or spot a large, dark, low-lying cloud, especially one that is rotating, know where to go.

• The safest place is a basement. If you don’t have a basement, go to an inner hallway or smaller inner room with no windows, such as a bathroom, closet, stairwell or space under the stairs. Go the center of the room, get under something sturdy that can be a shield from flying debris or a collapsed roof.
• Stay away from windows and skylights.
• Avoid gymnasiums, auditoriums or other rooms with a large expanse of roof.

What to do

• Crouch in the “egg” position. As a last resort, crawl under a desk or sturdy table.
• Cover your head and neck with your arms to protect from flying debris.
• If you live in a mobile home or are in a mobile classroom, go to a prearranged shelter. If no shelter is available, go outside and lie on the ground, in a ditch or depression if possible. Cover your head and neck with your arms and wait for the storm to pass.
• Never try to outrun a tornado in a vehicle, which can be easily tossed by a tornado. If you see a funnel cloud or hear a tornado warning issued, get out of the vehicle and find shelter, but not under an overpass or bridge. If no shelter is available, lie on the ground in a ditch or depression if possible, and cover the back of your head and neck with your arms.

The National Weather Service and the Federal Emergency Management Agency have more information on how to protect yourself from a tornado.

This story was originally published April 12, 2018 at 3:28 PM with the headline "It's prime tornado season in North Carolina. Know what to do before a storm hits.."