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Secrets of the St. Lawrence

The wind in your sails - Under the stars

A bay at the mouth of a steep valley

22:00. It's time we were all in bed. New horizons await us tomorrow. 23:18. All hands are jolted awake.

The boat is straining at its anchor. It's shuddering in the wind. No one expected this on such a fine, clear night after such a beautiful, warm day. It's katastrophic!

Land breeze

The calm before the storm. A few hours after the sun sets, it's time for the air from the shore to flow out to sea, but this phenomenon is not as strong as the sea breeze.

On a clear night, the cooler air from the shore will replace the warmer air over the sea.

This is known as the land breeze. It blows until morning.

Land breeze - At night wind blows from the shore to sea to replace air rising over the water.

Katabatic wind

While the land breeze is rather gentle, not so the katabatic wind. It doesn't believe in sweet dreams.

After a warm, windless and cloud-free summer day, the katabatic wind will blow in strong gusts. The cooler air from above will flow down the deep valleys and rush out to sea.

This local wind, which tends to spoil the most pleasant nights, can easily reach 25 or even 30 knots. It blows from late evening until sunrise. Kata means "downward".

Katabatic wind - At night cool air over a valley will flow down its slopes and pick up speed as it reaches the water.

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