Thunderstorms & Lightning

Thunderstorms are frequent around coastal areas. Although Florida thunderstorms are generally less than 15 miles in diameter, they can grow vertically to great heights in excess of 10 miles high into the atmosphere. This stacking effect of concentrated moisture can explain why a Florida thunderstorm directly overhead could produce four or more inches of rain in less than an hour while a location a few miles away may see only a trace. 

Thunderstorm Watch

A thunderstorm watch means conditions are favorable for thunderstorms to produce wind gusts to 58 mph or stronger, or hail in the watch area. Watches are issued four to six hours at a time and can cover several counties. Take cover if a severe thunderstorm is approaching. 

Thunderstorm Warning

A thunderstorm warning means a severe thunderstorm has been detected by radar or a trained spotter. Take cover if you are in or near a severe thunderstorm area. 

During a Thunderstorm

  • Postpone outdoor activities.
  • Protect belongings from power surges, avoid using a telephone or any electrical appliances
  • Avoid touching metal. Utility lines and metal conduct electricity
  • Avoid trees and telephone poles
  • Stay away from water, water conducts electricity
  • Watch for flash flooding
  • Stay indoors and away from windows during a storm

Lightning Storms

A lightning storm is a powerful electrical discharge produced during a thunderstorm. The electric current is very hot and causes the air around it to expand very quickly, which in turn makes thunder. Sometimes it happens between clouds. Sometimes, in the rain, it goes from cloud to ground. If it goes from cloud to ground, it can strike a person. 

Among Florida's weather dangers, lightning is the number-one killer. Lightning kills more people than hurricanes and tornadoes combined.

The 30-30 Rule

When you see a lightning flash, count the number of seconds until you hear its thunder. If the thunder rolls in 30 seconds or less, the storm is already close enough to be dangerous. After the storm, remain indoors for at least 30 minutes after hearing the last clap of thunder. 

How to Protect Yourself from Lightning

In the event of an approaching lightning or thunderstorm, seek shelter immediately. Go inside. There is no safe place outdoors when thunderstorms are in your area. Lightning safety is simple, know when you are in danger and where to go for safety.

Indoor Safety Tips

  • Stand clear of windows, doors, and electrical appliances
  • Unplug appliances before a storm nears, never during
  • Avoid contact with pipes including sinks, baths, and faucets
  • Do not use the hardline telephone except for emergencies. 

Outdoor Safety Tips 

  • Follow the 30/30 rule
  • Immediately get away from pools, or other bodies of water
  • Get off the beach
  • Never use a tree as a shelter
  • Avoid standing near tall objects
  • Keep away from metal objects including bikes, golf carts, umbrellas, fencing, machinery, etc
  • Get indoors or in a hard-topped vehicle
  • Remain sheltered for 30 minutes after the last flash of lightning

How to Take Precautions if on a Boat

If a thunderstorm and lightning catch you while afloat, remember that gusty winds and lightning pose a threat to safety:

  • Put on your life jacket and prepare for rough seas.
  • Stay below deck if possible.
  • Keep away from metal objects that are not grounded to the boat's protection system.
  • Don’t touch more than one grounded object at the same time so you don't become a shortcut for electrical surges passing through the protection system.