Marine Weather

Presented by:  John Jourdane

John Jourdane has sailed over 350,000 miles making him one of the most experienced offshore sailors in the world today.  He has crossed between the US West Coast and Hawaii 54 times, has crossed the Atlantic Ocean 12 time, and sailed around the world 3 times, including 2 Whitbread Round the World Races. He is also the author of “Icebergs, Port and Starboard”, “Sailing with Scoundrels and Kings” and “Modern Weather for Sailors”.


Expedition Weather Routing

An introductory course in Expedition routing software. The course covers: Using the Settings buttons and Tool bar, installing charts, navigating around the charts, changing predictor lines, and using dividers. Installing polars, getting grib files, setting up a course, editing a course, optimizing the course, comparing courses of different weather models. Using the results from the optimized route. Showing tidal currents. Setting up instrument boxes. Using strip charts, and updating polar files from sailing tests. Using sail charts. MOB.

John has used Expedition on races and deliveries for over 10 years, and teaches “Weather for Sailors” at OCC School of Sailing & Seamanship.

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Weather for Sailors

The main objective of this course is to explain Offshore, as well as Coastal weather for sailors, beginning to expert. Perhaps most importantly, it will explain how to interpret weather maps, and how to use onboard routing software to get GRIB files and run optimized routes. The course also shows how to use mid-level weather maps (500 mb) to forecast the movements of the weather systems reported on a surface-analysis map.  A handout will be given, which provides a list of useful sources of weather information. No test is given and no certification issued.

Topics covered include:

  • Weather Forecasting History
  • Weather Basics
  • Synoptic Weather – Highs, Lows, Fronts and Current
  • Models and Grib Files
  • Satellite Images
  • Local Conditions
  • Using Clouds to Predict Weather
  • Planning Before a Sail
  • Where to Get Weather Information
  • Marine Communications
  • Getting Weather Aboard Your Boat
  • Weather Routing
  • Racing to Hawaii
  • Attendees are encouraged to bring their laptops and try out weather websites.

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