30/30 Lightning Rule
When training at Curl Curl please be aware of the 30/30 Lightning Rule that MWNA endorses.
To judge how close lightning is, count the seconds between the flash and the thunder clap. Each second represents about 300 meters. If you can count less than 30 seconds between the lightning strike and the thunder, the storm is less than 10 km away and there is an 80 percent chance the next strike will happen within that 10 km. If you count less than 30 seconds, take shelter, preferably in a building or all-metal automobile (not a convertible top) or in a low-lying area.
30 seconds: Count the seconds between seeing lightning and hearing thunder. If this time is less than 30 seconds, lightning is a potential threat. Seek shelter immediately.
30 minutes: After the last lightning flash, wait 30 minutes before leaving shelter. Half of all lightning deaths occur after a storm passes. Stay in a safe area until you are sure the threat has passed.