'Undescended' tornado escaped detection

WHITE OAK - Cleanup from a Thursday tornado continues in southern Colbert County as northwest Alabama braces for another round of severe weather.

Mike Coyne, meteorologist in charge of the National Weather Service office in Hunstville, confirmed Friday that a tornado was responsible for damage to homes, a church, utility buildings and trees along Colbert 48, about 3 miles south of Alabama 157. He said the tornado, which touched down about 3:45 p.m., packed winds of up to 100 mph. No injuries were reported.

Coyne said the tornado snapped the trunks of large trees.

The tornado was classified as an EF-1 on the Enhanced Fujita scale. Tornadoes are rated EF-0 to EF-5 based on their strength, with EF-5 being the strongest.

Coyne said he suspects the twister was what meteorologists call an undescended tornado. The twister was not detected on weather radar and a tornado warning was not issued before it struck.

"The radar beam does not pick up what is going on at ground level," he said.

"Unlike most tornadoes that form high in a cloud and descend to the ground, undescended tornadoes form close to the ground. They typically don't last very long, just like this one."

Witnesses to the White Oak tornado said the funnel cloud seemed to appear out of nowhere and was gone in less than a minute.

Mike Melton, director of the Colbert Emergency Management Agency, is satisfied with Coyne's explanation as to why a tornado warning was not issued.

"There was absolutely nothing on radar to even indicate a tornado was forming, much less that one had touched down," Melton said.

Another possibility is that the tornado formed, touched down and was gone between sweeps of the radar beam.

While rare, tornadoes can form in the blink of an eye, Coyne said.

"When we issue a tornado watch as we did Thursday, it means conditions are favorable for tornadoes to develop," he said. "Some tornadoes develop so quickly that it is impossible for us to get a warning out. Any time there is a tornado watch, people need to keep an eye on the weather and be ready to seek shelter."

Coyne said there will be a slight chance of tornadoes again Sunday as another storm system moves across north Alabama.

"The set-up for tornadoes will not be as strong as it was Thursday, but the potential for tornadic storms could exist," Coyne said. "Everyone needs to be weather aware as the storms come through in case they reach strong or severe levels."

Sunday's storms will come in advance of a cold front that could cause temperatures to drop below freezing Monday and Tuesday nights.

Dennis Sherer can be reached at 740-5746 or dennis.sherer@TimesDaily.com.