Understanding & Avoiding Thunderstorms
Understanding & Avoiding Thunderstorms
Thunderstorms can quickly spoil an outing in many ways—strong winds, large waves, dangerous lightning, waterspouts, or visibility-limiting rain. This four-hour clinic will examine the various types of thunderstorms and the ingredients that lead to their formation. The clinic will cover why thunderstorms often ‘pop-up’ late on summer afternoons and why some storms have short life-spans while others persist for several hours. The clinic will also introduce the many readily-available resources for forecasting and monitoring thunderstorms.
The clinic is designed for all boaters (power and sail) who would like to reduce their chances of a hair-raising or windswept encounter with a thunderstorm.
You will learn the following at the clinic:
- A few basic weather principles.
- How to decode the confusing symbols, color shading, and meteorological shorthand on weather forecast maps.
- How to recognize the large and small-scale weather patterns that promote thunderstorm development.
- The ingredients needed for thunderstorm development and their life-cycle.
- How to forecast the potential and nature of severe weather.
- The dynamics of lightning and a review of the latest advice on lightning protection for your boat.
- How to use Doppler Weather Radar to assess the development, monitor the evolution, and track the movement of thunderstorms.
- The terminology used by the National Weather Service during hazardous and severe weather events.
The four-hour clinic combines classroom instruction, case studies, and exercises to create an engaging learning experience.
Click here to download the flyer for this clinic.
About The Presenter

Mark Thornton has been boating on the Great Lakes for more than 30 years. Mark recently transitioned from sailing and now owns Osprey, a Mainship 34 Pilot. He is a 2006 graduate of the Penn State University Certificate of Achievement in Weather Forecasting, a two-year program that develops skills in general, tropical, and severe weather forecasting.
He is the president of LakeErieWX LLC, a company dedicated to providing marine weather education and forecasting resources for recreational boaters (www.lakeeriewx.com). Mark publishes a marine weather blog and teaches basic forecasting seminars to recreational boaters during the off-season. He has served as the Race Meteorologist for the Bayview Race to Mackinac since 2014. Mark is employed as a Teaching Assistant in the Certificate of Achievement in Weather Forecasting Program at Penn State University.
Click here to read about my marine weather forecasting seminars, webinars and presentations. Click here for the current schedule of educational programs.
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Email: Mark@LakeErieWX.com
Phone: 440.250.9179
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February 18, 25, & March 4, 2025
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Great Lakes Marine Weather Essentials
February 20 & 27 and March 6 & 13, 2025
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Understanding & Avoiding Great Lakes Thunderstorms
March
18 & 25, 2025
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Cruisers University - Annapolis Boat Shows
October 2025
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Click here for the complete seminar schedule.
Seminar Reviews
"You have a passion for meteorology that is contagious and a gift for communicating a complex subject.".
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