We noticed a significant ‘lightning jump’ around 1820Z in the ENI time series which was indicative of the updraft increasing in strength and size. Not long after that at 1830Z, the overshooting top detection picked up on an overshooting stop associated with the same storm. It makes sense that we would see the lightning jump first, then get the overshooting top detection a bit later as the momentum of the growing updraft catapulted it over the tropopause.

-Helen Hunt