HUNTSVILLE, AL - A lightning flash 50 miles long, thundersnow, and gravity waves rippling through the air causing some of the heaviest snowfall in North Alabama records.

Those were surprise findings researchers from NASA and the University of Alabama in Huntsville recorded when they ventured out into this month's snowstorm. The storm dumped 8.9 inches of snow on Huntsville over the night of Jan. 9-10.

Dr. Kevin Knupp, professor of atmospheric science and director of UAH's severe weather research, deployed his resources that night. His team launched balloons every three hours while the snow fell, even though it meant being outside prepping the balloons for some 20 minutes at a time, and it used two lightning detector networks and three Doppler radars.

"We were studying the storm's 'comma,' the area of small-scale waves or instabilities near the end of a storm system," UAH doctoral student Ryan Wade said. "Those instabilities can dump large amounts of snow over small areas. That's why you might have a storm that drops 4 inches of snow across a hundred miles, but 8 inches in one place and a dusting in the other "

The UAH team got more than it expected, including the thundersnow and lightning. Seven flashes were recorded, including one stretching 50 miles from the top of Monte Sano to Moulton.

Lightning is rare in snowstorms, but can happen when updrafts carry ice particles aloft where they collide and swap electrons, building an electrical charge. However, sustained updrafts are also uncommon in snowstorms. That's where the gravity waves come in, Knupp said.

Wind blowing out of the east on the night of the storm bumped into and was pushed over Monte Sano, a university press release said. In a gravity wave, which can generate heavy snow, air is pushed up ahead of the wave and falls down the back.

Knupp said 11 gravity waves rippled across Huntsville and Madison County that night. They cause rapid cooling in clouds, and that might have triggered the heavy snow. One wave passed over moments before a National Weather Service employee reported an inch of snow fall in 20 minutes, UAH said.

The team did find the storm waves they were looking for. "At one point, between 9 p.m. and midnight, the Huntsville airport reported four inches of snowfall in one hour," Knupp said. "That might happen in the Midwest, but not often. It will be very rare down here. I won't be surprised if that was caused by the interaction of one of these bands with a gravity wave."

Now, that the storm is passed, Knupp and his team have an abundance of riches. There's more data than they can analyze, he said. UAH and NASA may team up to seek a grant to study the data.