From the figures in the paper, it looks like some of the detectors started picking up an increase a minute or more before the lightning flash. However, 2-3 of t

From the figures in the paper, it looks like some of the detectors started picking up an increase a minute or more before the lightning flash. However, 2-3 of the detectors also picked up increased gamma counts that then died out before the flash. It would be interesting to see the data on a longer time scale, to see how often there's an increased count with a flash at some later point, or no flash at all.