How many tornadoes have there been in Asheville, Buncombe? What to know about mountain twisters.

The first tornado in Buncombe County in over 20 years touched down in Black Mountain in the early hours of May 9.

Several homes were damaged during the storm, trees were uprooted and a communications tower at the Black Mountain Fire Department was toppled.

However, thankfully for the community, the tornado was overall mild, causing no loss of life in the area it affected. In fact, for as long as the National Weather Service has kept records, there has never been a tornado in the Buncombe area stronger than an F1 rating.

Meteorologists explain why the area has been so fortunate, and what the community should know in case of any future tornadoes.

More: Tornado, Buncombe County's 1st since 1999, touches down in Black Mountain, damages homes

Has there ever been a tornado in Asheville? Buncombe?

While there have certainly been tornadoes in Buncombe County and surrounding areas, as the community saw when an F1 tornado touched down in Black Mountain last week, they are exceedingly rare.

Justin Lane, a meteorologist for the NWS, said that there have only been seven other tornadoes in Buncombe County since 1950, all of which were F0 or F1. The last tornado to touch down in the area before this year was over 20 years ago in 1999.

The full list of tornadoes Lane provided were:

• 1976 - Touched down in the Candler area.

• 1976 - Touched down in the Candler area.

• 1977 - Touched down in the area between Leiscter and Weaverville.

• 1977 - Moved from Madison into areas east of Weaverville.

• 1977 - On the same day as the Madison tornado, another tornado moved from Mars Hill to clip the edge of Buncombe County.

• 1993 - Touched down in the Asheville area.

• 1999 - Touched down in the Asheville area.

• 2024 - Touched down in the Black Mountain area.

Can tornadoes form in the mountains?

Tornadoes can form in the mountains but are rare in any mountainous area, Buncombe County included, due to the nature of the terrain.

"The complexity of the terrain interrupts flow patterns and the storms that would cause them to produce tornadoes," Lane said. "So, storms that can produce tornadoes are pretty dependent on uninterrupted patterns of wind flow into them."

Lane said that the other factor that prevents tornadoes from forming in the mountains has to do with the necessity of atmospheric instability in their formation.

"Mountains tend to be more stable than the surrounding lower elevations just because the temperatures are cooler," Lane said.

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How do tornadoes form?

The National Oceanic and Atmospheric Administration provided a recipe on a devoted webpage, listing the ingredients needed for a tornado to form. First, they mention instability, a change in wind speed and/or direction with height. This instability can allow strong updrafts to develop, and when wind shear further increases this strength, rotation and eventually tornadoes can be created.

Tornado watch vs. tornado warning

An NOAA guide explained the classifications of tornado alerts on a dedicated website. The definitions are:

• Tornado Watch - Tornadoes are possible in and near the watch area. Review and discuss your emergency plans, take inventory of your supplies and check your safe room. Be ready to act quickly if a warning is issued or you suspect a tornado is approaching.

• Tornado Warning - A tornado has been sighted or indicated by weather radar. There is imminent danger to life and property. Move to an interior room on the lowest floor of a sturdy building. Avoid windows. If in a mobile home, a vehicle, or outdoors, move to the closest substantial shelter and protect yourself from flying debris.

Lane said that there have been under 10 tornado warnings issued in the area since 2015, and estimated one or two tornado watches yearly.

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How do you know if a tornado is coming?

Forecasters and storm spotters with the NOAA and other organizations are trained to recognize thunderstorm features that make tornado formation more likely including visual cues and patterns in radar images. Storm spotters are trained to recognize tornado conditions and report back to the NWS. These people can be emergency managers or simply locals with interest in severe weather who have taken the formal storm spotter training.

While the best bet for knowing when a tornado is coming is generally to keep an eye on severe weather alerts, there are also ways to identify a tornado with the naked eye. The Federal Emergency Management Agency provided the following list of signs that may mean a tornado has formed:

• A rotating, funnel-shaped cloud that extends from a thunderstorm toward the ground.

• An approaching cloud of debris especially at ground level, even if a funnel is not visible.

• A loud roar similar to a freight train or a strange quiet occurring within or shortly after a thunderstorm.

• A change in the color of the sky, often an unusually dark/black thunderstorm or one taking an eerie brownish, green or yellow color.

• Debris dropping from the sky or rising up into the air, particularly in a swirling motion.

What part of the house is safest during a tornado?

The NOAA advises moving to an underground shelter, basement or safe room if one is available. If you don't have access to a below-ground area, the next best choice is to move to a small, windowless interior room or hallway on the lowest level of the building. As for mobile homes, the NOAA advises occupants to leave immediately and go to the nearest sturdy building or shelter.

What to do if you're in a car during a tornado

Finally, if you are caught in a vehicle while flying debris is occurring and you are unable to find safe shelter, last resort options are to stay in your vehicle with your seat belt on, put your head down below the windows and cover it with your hands and a blanket if possible. If you can safely get noticeably lower than the level of the roadway, it's a better bet to exit the car and lie in that area, covering your head with your hands.

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Iris Seaton is the trending news reporter for the Asheville Citizen Times, part of the USA TODAY Network. Reach her at iseaton@citizentimes.com.

This article originally appeared on Asheville Citizen Times: Tornadoes in Western NC: How many before Black Mountain?