A 440-mile-long “Megaflash” Enters the Record Books as the Longest Lightning Bolt Ever Observed

Imagine a lightning bolt igniting in a large thunderstorm about San Diego and then taking pictures north practically all the way to San Francisco.

If that seems unachievable, consider that just this kind of a prodigious lightning flash has now been verified — not in SoCal but in South The usa. It took place on Halloween of 2018, when a system of large thunderstorms boiled up about southern Brazil and spawned a one bolt stretching across 440 miles, from the Atlantic coast all the way into Argentina.

Longest Lightning Bolt

Satellite picture displaying the report extent of a lightning flash about Brazil October 31, 2018. (Resource: Entire world Meteorological Business)

Late last thirty day period, the Entire world Meteorological Business accredited it as the longest one lightning flash on report. This much surpasses the past report of 199.5 miles, established by a flash on June twenty, 2007 about Oklahoma.

WMO’s Committee on Weather and Climate Extremes also announced a new report for longest duration flash: 16.seventy three seconds from a flash that produced about northern Argentina on March 4, 2019. This once yet again blew the past report — seven. 74 seconds about France in 2012 — appropriate out of the, very well, cloud…

Record Setting Megaflashes

The two report-environment lightning flashes, one about Brazil which is the longest ever documented, and yet another about Argentina that persisted for a longer period than any observed right before. (Credit: WMO)

“These are amazing records from one lightning flash situations,” claims the WMO’s Randall Cerveny, quoted in a WMO release about the episodes. “It is most likely that even bigger extremes still exist, and that we will be capable to notice them as lightning detection technologies enhances.”

Monster Storms Spawn Megaflashes

These report-environment bolts ended up not spawned by each working day thunderstorms, the form of compact storms that flash often and therefore deplete the electrical rates that give rise to lightning. In just about every situation, they ended up the item of a gigantic collection of thunderstorms performing as a one system — a phenomenon meteorologists contact a “Mesoscale Convective Method,” or MCS.

The large overhanging anvils and raining areas of these monsters have massive electrified clouds with lower flash rates, which enables rates to develop up drastically. When a flash does ignite, it can propagate across a wide distance and for a long duration.

The new report-setters came underneath the discerning eye of what was then a newish temperature satellite, GOES-16. The 1st of a new generation, GOES-16 carries an instrument that consistently maps all lightning activity across North and South The usa.

The Geostationary Lightning Mapper, or GLM, aboard the satellite detects light-weight emitted by lightning at the tops of clouds, during the two night time and working day. Info from the instrument enable with forecasting of extreme storms and potentially harmful phenomena this kind of as hailstorms, microburst winds, tornadoes, and hurricanes.

The lightning mapper aboard GOES-16 provides an unmatched opportunity to keep track of two hotspots for the progress of Mesoscale Convective Techniques: the Great Plains in North The usa, and the La Plata basin in South The usa. “This would make the GOES-16 GLM an superb system for documenting extraordinary lightning,” researchers concluded in a new paper on the report-environment flashes. GLM much exceeds the capabilities of its predecessors, they say.