Lightning can strike dozens of miles away from the actual thunderstorm itself.
This lightning started in southeastern Kansas and propagated about 250 miles across parts of Oklahoma and Missouri in real-time:
The GOES16 lightning mapper captured an impressive lightning flash, associated with a squall line that was advancing across the plains that night, that propagated for about 250 miles across portions of Oklahoma, Kansas and Missouri on October 22, 2017.
A squall line is a group of storms arranged in a line, often accompanied by “squalls” of high wind and heavy rain. Squall lines tend to pass quickly and are less prone to produce tornadoes than are supercells. They can be hundreds of miles long but are typically only 10 or 20 miles wide.
The new satellite was in orbit in May when the Pacific Northwest was hit by a rare severe weather outbreak:
Rapid increases in the amount lightning are often a signal that a thunderstorm is strengthening and could become more dangerous.