RYA Yachtmaster Advanced Meteorology

Question 1

A 'trough of low pressure' on a synoptic chart (weather map) is characterised by:

Accepted Answer

A line of closely packed isobars extending from a low centre — often associated with wind shifts, squalls, and deteriorating weather

Answer

A region of high pressure

Answer

An area of stable, settled weather

Answer

A wind direction change from west to east

Question 2

The Buys Ballot Law states that in the Northern Hemisphere:

Accepted Answer

If you stand with the wind on your back, low pressure is to your left (port)

Answer

High pressure is always to the north

Answer

Wind always blows from south to north

Answer

If you face the wind, low is to the right

Question 3

A veering wind in the Northern Hemisphere (shifting clockwise, e.g., SW to W to NW) typically indicates:

Accepted Answer

A cold front has passed — improving weather behind it

Answer

A warm front is approaching

Answer

Fog is developing

Answer

A tropical cyclone is nearby

Question 4

What is 'radiation fog', and when is it most likely to affect an offshore passage?

Accepted Answer

Fog that forms over land overnight as land cools radiatively, and drifts offshore in the morning with the land breeze — most likely in light wind, clear-sky anticyclonic conditions

Answer

Fog caused by nuclear radiation

Answer

Fog associated with warm fronts only

Answer

Fog that forms only in winter

Question 5

For a cross-Channel passage, which Met Office forecast service provides the most detail for skipper-level planning?

Accepted Answer

Inshore Waters Forecast combined with the 5-day shipping forecast text and synoptic chart — plus GRIB files for wind modelling

Answer

BBC Radio 4 forecast alone

Answer

A smartphone app without verified meteorological data

Answer

VHF Channel 16 only

Question 6

A 'secondary depression' forming on a cold front can be particularly hazardous because:

Accepted Answer

It may intensify rapidly and is often not forecast as accurately as the primary low, causing unexpected severe conditions

Answer

It brings clear skies and no wind

Answer

It only affects the Eastern Channel

Answer

It always tracks south of the English Channel