Land: Smoke rises vertically. Sea: Sea like mirror.
Land: Smoke drifts slowly downwind. Sea: Ripples with appearance of scales: no foam crests.
Land: Leaves rustle. Sea: Small wavelets; crests of glassy appearance, not breaking.
Land: Leaves are in motion. Sea: Large wavelets; crests begin to break; scattered whitecaps.
Land: Small branches on trees move. Sea: Small waves, becoming longer; numerous whitecaps.
Land: Small trees sway. Sea: Moderate waves, taking longer form; many whitecaps; some spray.
Land: Large branches sway. Sea: Larger waves forming; whitecaps everywhere; more spray.
Land: Whole trees in motion. Sea: Sea heaps up; white foam from breaking waves begins to be blown in streaks.
Land: Twigs and small branches break off trees. Sea: Moderately high waves of greater length; edges of crests begin to break into spindrift; foam is blown in well-marked streaks.
Land: Large branches break off trees; slight structural damage. Sea: High waves; sea begins to roll; dense streaks of foam; spray may reduce visibility.
Land: Trees broken; minor structural damage. Sea: Very high waves with overhanging crests; sea takes white appearance as foam is blown in very dense streaks; rolling is heavy and visibility is reduced.
Land: Widespread damage. Sea: Exceptionally high waves; sea covered with white foam patches; visibility further reduced.
Land:Violent movement of trees and much destruction. Sea: Air filled with foam; sea completely white with driving spray; visibility greatly reduced.
1 knot equals 1.15 statute miles per hour
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