TUCSON, Ariz. - Tucson weather specialists are watching Hurricane Florence for something other than its powerful winds and rising water.
Specialists at Vaisala have ways to track lightning all over the world and they see lightning behave in surprising ways inside a hurricane.
While forecasters and people in the path of Hurricane Florence worry about its winds and water, specialists in Tucson are watching the lightning the storm creates.
Vaisala is headquartered in Finland but its Tucson office pulls in lightning data from a worldwide network of sensors.
When Florence was at its strongest, Vaisala's sensors saw a rare phenomenon---circles of lightning lining the eyewall.
Vaisala Meteorologist Ron Holle says, “And it indicates a really strong, well-defined storm"
Scientists have only been able to see the effect they call enveloped eyewall lightning for the past two or three years. They're more likely to see it in Pacific typhoons that are often much stronger than Atlantic hurricanes.
Doctor Holle says there's a typhoon in the Philippines that makes Florence look puny.
"This one is forecast right now to have gusts to 175 knots which is getting close to 200 miles an hour."
Eyewall lightning appeared in Typhoon Lane that threatened Hawaii last month.
Lightning is basically caused by static electricity as the clouds rub onto themselves but Doctor Holle says to get those conditions you have to get into the upper parts of the atmosphere where the air is below freezing. The mystery here is how do you get that sort of strong, sustained updraft when you have hurricane force winds going horizontally in a tight circle?
A better understanding of lightning in hurricanes can help forecast a storm’s strength and position because Vaisala's sensors can detect lightning farther out to sea than radar can reach.