What If You See Lightning on the Horizon!?!


It’s 10:00 PM. You’re 200 nm offshore and the cloud cover has been building all day. Lightning is now a regular occurrence.


For years while on long distance passages, others on the crew and I discussed a wide range of “what if scenarios” while sitting on the rail.  Some had a basis in our respective pasts. Others were merely hypothetical.  All provided us with some insights and options if and when we were ever faced with similar problems.  Confronting lightning on a dark and stormy night is merely one of many situations we’ve considered, faced and overcome.

Lightning isn’t always a major problem, but it always deserves respect. Often the lightning that occurs at higher altitudes and is confined to the clouds can last for hours. Ground strikes may not be present, and the upper level light show can be more drama than problem. However, it is my opinion that whenever lightning is present, I always assume that there could be a ground strike, and it could affect my own vessel.

One night I was awakened by a crewmember who wanted me to come up on deck to see something.  “What is it?” I asked.

“I don’t know, but I want you to look at it,” he said.

Once up on deck, he pointed up the rig, and the top third of the mast and rigging was glowing green.  “What is it?” he asked.

“I don’t know, but don’t touch the backstay!” was my apprehensive reply.  It turned out to be St. Elmo’s fire, a situation in which the atmosphere is highly charged and is often a precursor to a lightning strike.

The wind was up, and the autopilot wasn’t available so I took the wheel and asked the crew to put the handheld GPS in the oven. If we were hit by lightning, any number of things could happen: through hulls or chain plates could be blown out, electronics could be fried, and even a magnetic compass could be re-magnetized, making it ineffective. The oven would act as a Faraday cage, protecting the handheld GPS from electrical damage.

Everyone else was sent below, including the crewmember with the most medical training. Log entries were made every half hour and notes were added to include the direction of the wave patterns. If we lost all navigation, including the handheld GPS, I knew that we could steer by the stars, but while the cloud cover persisted, we would need to rely on wave patterns – a sketchy way to get anywhere, but perhaps better than nothing.

Most modern sailboats are well grounded and protected from lightning in most cases.  Not all.  While at sea, friends of mine have been hit by lightning.  Fortunately, they have all survived, but the event caused a variety of problems.  Preparation for the worst of them, or avoidance whenever possible, is the best that can be offered.  What would you do?




Author: Blue Water Sailing