You are 4 hours into an 8-hour passage when visibility drops below 100m. You are 12 miles off a clear anchorage and 4 miles from shipping lanes. What are your options and how do you choose?

A. Options: 1) Continue at minimum safe speed with full radar/AIS watch and fog signals; 2) Divert to the anchorage (12nm = ~2h at 6kn); 3) Anchor where you are in appropriate depth clear of lanes. Choose based on: radar capability, crew experience, traffic density, whether lanes can be safely avoided. Anchoring is underused but often the best option

B. Maintain course — deviating in fog increases collision risk more than staying put

C. Reduce to 1 knot and wait — the fog will clear within the hour

D. Continue at maximum speed to clear the fog bank as quickly as possible

A. Barometric tendency only matters above Force 6 — below that, pressure changes have no predictive value

B. A fall of 6 hPa in 3h is insignificant — barometric changes only matter over 24h

C. A rapid fall (>6 hPa in 3h is defined as "very rapid" in MET Office guidance) indicates an approaching vigorous depression — imminent deterioration. Seek shelter, shorten sail, check position and proximity to lee shores, and reassess the passage plan immediately

D. This indicates a high pressure system building — expect improving conditions

A. Formed when a cold front catches a warm front — the warm sector is lifted off the surface. An occlusion brings a prolonged period of disturbed weather with cloud, rain, and variable winds; the warm sector advantages (relatively settled weather) are lost

B. An occlusion only forms in tropical waters — not relevant to UK sailing

C. Occluded fronts always bring fog and light winds

D. An occluded front is a front that has weakened and no longer has significant weather