The Daily Times

The storms and tornadoes that have struck East Tennessee within the last year have apparently left many residents concerned.

A group of more than 50 from Blount County and surrounding areas filled the Blount County Emergency 911 Communications Center Tuesday night, looking to learn more about storm spotting during a weather spotter course hosted by the National Weather Service (NWS) in Morristown.

NWS Senior Forecaster and class instructor David Gaffin told those gathered at Tuesday’s class that attendance at such spotter courses has grown exponentially since the storms and tornadoes beginning March 2011.

“After a large storm outbreak people tend to get a renewed interest in storms,” Gaffin said.

Those who attend the courses also gain a little more than knowledge. They become certified weather spotters.

Recent storms, tornadoes

Gaffin started the class by talking specifically about last spring’s storms, which began when an EF3 tornado struck Greenback March 23.

“On April 27 we had supercells everywhere,” he said.

“And not only were they everywhere, but it seemed that every supercell was producing a tornado, which is unusual ... most people at least know someone who was hit by a tornado.”

According to records, the number of tornadoes touching down in Tennessee has greatly increased since 1955. Gaffin said there are probably several meteorological as well as non-meteorological reasons for that, citing the greater number and coverage of spotters as one reason for the increase in reported tornadoes in just the last decade.

March, April and May are the busiest months for storms, especially tornadoes, Gaffin said, which will probably comes as no surprise to the people of Greenback, where the most recent confirmed tornado struck Feb. 29.

Gaffin explained that the last storm “superbreak” in the state was in April 2011, which greatly exceeded the previous superbreak in April 1974. And East Tennessee happened to lie right in the middle of both.

Visibility issues

“A lot of people think ‘Oh well, the mountains are going to protect us,’” Gaffin said. “No. What the mountains are going to do is keep the conditions from being favorable (for tornadoes) too often. But when the conditions are favorable, the mountains aren’t going to protect us.”

Another problem is that, due to the mountains and amount of moisture in the atmosphere, it makes spotting tornadoes much more difficult than in Midwest states.

Yet it doesn’t mean East Tennessee residents shouldn’t always be on the lookout for tornadoes, especially during the spring months. Gaffin explained a few of the conditions and cloud formations to look for:

• A mass of the cloud that’s lower than the rest of the cloud base of the storm. This mass is called a wall cloud. Residents should be looking at the back of the storm, where a tornado will originate. Make sure the wall cloud is hanging lower than the rest of the storm and is at least displaying a gradual rotation.

• Funnel clouds. If a funnel cloud is coming out of the wall cloud, and is at least halfway to the ground, it’s a tornado.

• Shelf clouds. These formations will look like a thick, cylindrical cloud mass stretching across the horizon at the front of a thunderstorm. Shelf clouds don’t always indicate a severe thunderstorm, but indicate strong winds in front of the storm. Shelf clouds do not need to be reported.

• All funnel clouds should be reported.

Things to include in a report to the NWS:

• What is the character and position of the storm?

• Is there a wall cloud?

• Always try to be as descriptive as possible.

• If calling in hail reports, use coin sizes for smaller hail. For larger hail, use standard ball-shapes, like a golf ball.

In case of a tornado, get to the lowest floor possible. Closets and stairwells are also good places to take cover. Under a bridge is an extremely dangerous place to be, Gaffin explained, as the wind will accelerate greatly as it crosses over the bridge. He said think pressing your thumb over a garden hose to push the water further. It’s the same forces at work, Gaffin said.

Storms pique residents’ interest

Knoxville resident and course attendee Paul Flynn backed up Gaffin’s claim that the uptick in storms has led to an increased interest in storm spotting.

“I’ve had an interest in watching the weather for a while,” Flynn said. “And the storms last year really peaked my interest.”

Alcoa resident and Blount County Rescue Squad member Janet Fraze said she took the course to be better prepared when the big ones do hit.

“That way we can tell when the storms are starting so we can be prepared,” Fraze said. “We’re always prepared for anything at the Rescue Squad.”

Residents who wish to report severe or unusual weather can call the NWS Morristown Spotter Line at 1-800-697-0075. The NWS can also be reached on Facebook or at http://www.weather.gov . Storm reports are used in the decision to issue warnings and many times are posted on the NWS Morristown website as summary reports.