STORMKEEPERSafety guides › Lightning and the 30/30 rule
What is the 30/30 rule for lightning?
When thunder roars, go indoors. Wait 30 minutes after the last thunder.
If you can hear thunder, you are close enough to be struck. Lightning can strike 10 miles or more from the storm.
- Go inside a building with plumbing and wiring, or a hard-topped car.
- Picnic shelters, tents and dugouts do not protect you.
- Stay inside until 30 minutes after the last thunder or nearby strike. Stormkeeper counts this down for you.
Source: National Weather Service. Reviewed 2026-10-07.
This guide is general safety information. When a warning is issued for your area, follow the instructions from the National Weather Service and local officials.
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