Lightning at sea is an electrical discharge associated with thunderstorms, occurring within cloud, between clouds, or between cloud and the water or vessel. In boating, it is a severe weather hazard because masts, antennas, rigging, rails, and wet decks can provide conductive paths for a strike or nearby induced current.

For sailors and power boaters, lightning risk affects route choice, watchkeeping, and onboard safety. A strike can injure crew, disable engines or electronics, corrupt navigation instruments, and damage communications, so crews should monitor Forecast Alerts, approaching Rain Radar, and sudden Wind Gust activity. During active lightning, reduce exposed deck work, avoid touching metal fittings, disconnect non-essential electronics if safe, and keep a backup navigation plan.

PredictWind forecasts help identify thunderstorm-prone periods through rain, cloud, pressure, wind, and model guidance before departure and while offshore. The Offshore App can download compact GRIB data via satellite, helping crews reassess timing, divert around squall lines, or delay a departure when convective weather increases lightning risk.

Glossary Terms

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