If you’re caught outside during a thunderstorm, go inside immediately.

If that’s not possible, the National Weather Service suggests:

• Stay away from open fields, hilltops and ridge tops.
• Avoid tall objects, including single trees. In the woods, gather near a group of low trees.
• If you are with several people, stand apart to avoid the possibility of sharing lightning current.
• If you’re camping, choose a low area. But remember that a tent offers no protection from lightning.
• Avoid anything that’s wet. Also steer clear of metal objects, including fences and poles.

Source: HealthDay