Copyright © 2022 Albuquerque Journal
SANTA FE – Los Alamos National Laboratory scientists – using lab software and a series of new satellites – recorded a pair of lighting megaflashes in 2020 that recently were confirmed as setting new records of distance and duration.
The longest-distance flash was detected over the southern United States and spanned more than 477 miles from Mississippi to Texas and the longest-duration lightning bolt, also detected in 2020, was recorded over Uruguay and lasted 17.1 seconds.
New geostationary satellites, launched by the government’s National Oceanic and Atmospheric Administration, have provided new and better eyes to track lightning events, LANL remote sensing scientist Michael Peterson told the Journal.
“We are always discovering that lightning can do some fantastic and sometimes terrifying things,” he said. “.. We can see flashes that are not just 100 kilometers (just over 62 miles) but 200, 300 even now 700 kilometers (almost 435 miles) across,” Peterson said.
“These are flashes that are far greater than the typical lightning which are usually 10 miles across,” he said.
Arizona State University’s Randall Cerveny, the chief of records confirmation for the World Meteorological Organization, called the record strikes “absolutely extraordinary” in an interview with the Associated Press.
Peterson, lead author in a recent article in the Bulletin of the American Meteorological Society, wrote that these record events occur in extraordinary thunderstorms.
They occurred in hotspots for what are called Mesoscale Convective System thunderstorms mainly in the Great Plains in North America and the La Plata basin in South America.
They are very large and organized with dozens of individual storm cells whose unique features can “produce unique hazards and effects you don’t see in ordinary thunderstorms,” Peterson said.
The NOAA satellites and instruments can detect all lightning and provide “real time information for forecasters and other people who need to know what the weather is doing,” Peterson said.
“GLM, this instrument, which stands for the Geostationary Lightning Mapper, is a fantastic tool for advising people on the lightning hazards around them,” he said.
The advancements have real world applications.
During lightning events clouds and light rain may not seem significant and may prompt people to be outside “but if they are electrified they can still cause problems,” Peterson said. “So what it means practically for the people on the ground is that you can have a lightning flash that starts well over the horizon where you can’t even see the storm that produced it but it can still strike anywhere around you.”
Peterson grew up in Minnesota and, with its prevalence of water and boating, the proverbial “bolt out of the blue” lightning strike was something that people constantly warned about and is a similar concept to the megaflashes.
The National Weather Service gets raw data from the NOAA satellites that “can produce potentially better forecasts,” Peterson said.
The data helps determine thunderstorm intensity, said meteorologist Brian Guyer with the National Weather Service in Albuquerque.
“If we see an increase in the in-cloud lighting flashes that’s an indication a storm is strengthening,” Guyer said.
That gives forecasters a longer lead time for thunderstorm warnings.
“Often in-cloud lightning precedes ground lightning strikes,” Guyer said.
Peterson noted, “it’s always important no matter what situation you find yourself in to appreciate the fact that lightning doesn’t always behave as we expect.”
He cited guidance from NOAA: “when thunder roars go indoors.”