||Calm, smoke rises vertically
||Water calm, mirrorlike (.25 ft. waves)
||Wind direction shown by smoke but not by windvanes
||Ripples with the appearance of scales (.5 to 1 ft. waves)
||Leaves rustle; wind felt on face; windvanes moved by wind
||Small wavelets on water; crests have a glassy appearance and do not
||Leaves and twigs in constant motion; wind extends light flag
||Large wavelets; crests begin to break; maybe scattered whitecaps.
3.5 to 5 ft.
||Wind raises dust and loose paper; small branches move
||Moderate waves; fairly frequent whitecaps 6 to 8 ft.
||Small leafed trees begin to sway
||Moderate, longer waves; many whitecaps; chance of spray. 9.5 to 13
||Large branches in motion; phone lines whistle
||Large waves form; white foam crests everywhere; probable spray.
13.5 to 19 ft.
||Whole trees in motion; difficult to walk against wind
||Sea heaps up; white foam starts to blow in streaks. 18 to 25
||Wind breaks twigs off trees; walking impeded
||Moderately high waves with crests beginning to break into foam
that's blown in white streaks. 23 to 32 ft.
||Slight damage to buildings occurs; shingles torn off roofs
||High waves; rolling seas; dense streaks of foam; wave crests begin
to topple, tumble and fall over. 29-41 ft.
||Trees uprooted; considerable structural damage to buildings
||High waves with overhanging crests; sea is white. 64-72 ft.
||Huge waves; air filled with spray; little visibility
73 ft. +