Total lightning — in-cloud plus cloud-to-ground — responds to a storm’s updraft. When the updraft strengthens, ice collisions multiply and the flash rate can double or triple in minutes, before the storm drops its worst hail or spins up a tornado. Forecasters call it a lightning jump, and studies put its lead time ahead of severe weather at several minutes to half an hour.
That is why these loops matter more than any single frame: a cell that brightens loop after loop is telling you its engine is revving. Cross-check it against radar and the SPC outlook, and if you are under it, check the alerts for your location.
