🔍 Key Concepts

• Storm movement and wind direction around a low-pressure center in the Northern Hemisphere • Typical seasonal pattern of thunderstorms on the Great Lakes • Historical pattern of the most destructive Great Lakes storms (track and direction)

💭 Think About

• Think about how winds circulate around a low-pressure system in the Northern Hemisphere and how that affects a vessel located north versus south of the storm track. • Which months on the Great Lakes are best known for severe thunderstorms versus gales and freezing conditions? Does that support a November–April peak for thunderstorms? • Consider famous Great Lakes storm events (for example, in November). From which general directions do the worst storms and gales usually arrive over the Lakes?

✅ Before You Answer

• Verify the direction of wind circulation around a low in the Northern Hemisphere (counterclockwise vs clockwise) and how that would feel on a vessel in different quadrants. • Check whether thunderstorm season on the Great Lakes is associated more with warm-season instability (late spring–summer) or cold-season conditions (late fall–winter). • Recall that many deadly Great Lakes storms are autumn gales; confirm from which quadrant (NW, N, NE, etc.) those typical systems approach the region.