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Weather for Sailors

This course is aimed at people who have spent some time outdoors, primarily on the water, who wish to understand more about how the weather works, where to get information from and how to interpret and use it. No prior weather tuition is required and it can be taught in one very full day. The syllabus is as follows:

 Global Weather Patterns

The Effect of Surface Temperature Differences – Thermal Wind Balance

The Coriolis Effect

The Ocean High Pressure Systems – How are they Formed?

Mid-Latitude Weather Systems

Air Masses

Clouds – What are they and What do they Mean?

The Life Cycle of a Mid-Latitude Depression

General Summary of Conditions as a Low Pressure System Moves Overhead

Case Study of a Depression

High Pressure Systems and their Interaction with Low Pressure Systems

The Interaction of Multiple Systems

Buys-Ballot’s Law

Some Localised Surface Phenomena

Changing the Surface Friction as Wind blows over Land and Sea

Being Headed or Lifted as You Sail Offshore

Convergence and Divergence 

The Boundary Layer

Sea Breeze

Land Breeze

Katabatic Winds

Chinook or Fohn Winds

Radiation (or Land) Fog

Advection (or Sea) Fog

Predicting Gusts

Using Upper Level Information to help with Surface Forecasting  

Will it Snow or Rain?

Will a Particular Low Deepen or Dissipate?

Can We Predict the General Path of the Lows?

 Tropical Weather Systems

The Inter-Tropical Convergence Zone

Trade Winds and the Ocean Highs

Tropical Waves, Squalls and Diurnal variation

The Madden-Julian Oscillation

El Nino and La Nina

Acceleration Zones and the Effect of Islands

Hurricanes – how they Start and Develop, and what Actions to take

Modern Numerical Weather Forecasts

Route Planning and Preparation

Publications, charts and on-line information

Passage Planning Case Study



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