The ground can remain dangerous for minutes after a lightning strike , and the safest rule is to stay away from the area until the storm has clearly moved on. A practical guideline is to wait at least 30 minutes after the last thunder before going back outside, because lightning hazards can still persist even after the rain seems to stop.

Why it stays dangerous

Lightning that hits the ground spreads current through the soil, and that current can injure people several meters away from the strike point. One source notes that ground current has caused injuries up to 15 to 30 meters from where lightning hit, so the danger is not just at the exact impact spot.

What to do

  • Stay indoors or in a hard-topped vehicle when thunder is still audible.
  • Do not stand near the strike point, wet ground, fences, trees, or metal objects.
  • Use the 30-minute rule : wait 30 minutes after the last thunder before resuming outdoor activity.

Simple rule of thumb

If you can still hear thunder, the ground nearby is still unsafe enough to matter. In other words, the danger after a strike is not measured in seconds — it is usually measured in the rest of the storm plus a 30-minute buffer.

TL;DR: Ground struck by lightning can stay dangerous immediately after the strike and beyond the storm’s last thunder; wait at least 30 minutes after the final thunder before going back outside.