RYA Weather Handbook

Synopsis

RYA Weather Handbook

Summary

Chapter 1: Understanding Weather

* Introduction: Importance of weather knowledge for sailors.
* Atmospheric Composition and Structure: Layers of the atmosphere, composition of air.
* Real Example: Check the weather forecast for your sailing destination before departure.

Chapter 2: Air Pressure

* Pressure Systems: Highs, lows, and fronts.
* Isobars and Pressure Gradient: Pressure lines and wind.
* Real Example: Identify a low-pressure system on a weather chart and predict its movement.

Chapter 3: Wind

* Wind Force and Direction: Beaufort scale, wind instruments.
* Wind Generation: Pressure gradients, coriolis force.
* Real Example: Forecast and prepare for strong winds during a coastal passage.

Chapter 4: Clouds

* Cloud Formation and Types: High, middle, and low clouds, cloud codes.
* Clouds as Weather Indicators: Interpreting clouds to predict storms, precipitation, or clear weather.
* Real Example: Observe and identify different cloud formations to forecast the weather for a race.

Chapter 5: Precipitation

* Types of Precipitation: Rain, snow, hail, fog.
* Causes of Precipitation: Condensation, evaporation, and freezing.
* Real Example: Predict the onset of rain or fog during a coastal cruise.

Chapter 6: Stability and Turbulence

* Atmospheric Stability: Stable, unstable, and conditionally unstable air.
* Thermal Inversion: Stable air layer that traps pollutants and creates clear skies.
* Real Example: Use atmospheric stability to predict the likelihood of thunderstorms or sea fog.

Chapter 7: Fronts and Depressions

* Weather Fronts: Cold fronts, warm fronts, occluded fronts.
* Depressions: Low-pressure systems with associated winds and precipitation.
* Real Example: Plan a sailing route to avoid crossing a cold front or depression.

Chapter 8: Anti-cyclones and Ridges

* Anti-cyclones: High-pressure systems with associated clear weather.
* Ridges: Extensions of anti-cyclones with lighter winds.
* Real Example: Time a passage to take advantage of calm winds and clear skies under an anti-cyclone.

Chapter 9: Weather Forecasting

* Types of Forecasts: Long-range, short-range, marine forecasts.
* Using Weather Forecasts: Interpreting forecasts, combining sources, applying to sailing plans.
* Real Example: Combine weather forecasts from multiple sources to make informed decisions during a voyage.