Weather & Hazardous Conditions Flashcards

Which cloud formation is most commonly associated with sudden, violent thunderstorms on the water?

Answer: Cumulonimbus

Cumulonimbus clouds are tall, anvil-shaped storm clouds that produce lightning, heavy rain, and strong gusty winds.

What does a rapidly falling barometer reading indicate for boaters?

Answer: Approaching storm or bad weather

A rapidly falling barometer means atmospheric pressure is dropping, which signals an approaching storm or deteriorating weather conditions.

When caught in a thunderstorm on a small open boat, what is the safest position for passengers?

Answer: Sit low in the boat away from metal objects

Sitting low in the boat and away from metal objects reduces the risk of lightning strike and keeps the center of gravity low in rough water.

What wind speed (in knots) typically signals small craft advisory conditions?

Answer: 21–33 knots

Small craft advisories are issued when sustained winds of 21–33 knots or hazardous wave conditions are expected.

If you see lightning strike the water nearby while boating, what is the immediate risk besides fire?

Answer: Electric shock through the water

Lightning can travel through water and electrocute anyone in or near the water, making it extremely dangerous to be overboard during a storm.

What is the safest action when fog reduces visibility to near zero on open water?

Answer: Slow down, post a lookout, and sound fog signals

Slowing down, posting a lookout, and sounding proper fog signals reduces collision risk and complies with Navigation Rules.

Which type of current hazard is most dangerous because it is invisible from the surface and can trap swimmers near a boat?

Answer: Hydraulic current near a dam

Hydraulic currents below low-head dams recirculate continuously, trapping people underwater in a deadly cycle called a 'drowning machine.'