||Less than 1
||Less than 1
||Sea surface like a mirror, but not necessarily flat.
||Smoke rises vertically.
||1 - 5
||1 - 3
||Ripples with the appearance of scales are formed, but without foam crests.
||Direction of wind shown by smoke drift, but not wind vanes.
||6 - 11
||4 - 6
||Small wavelets, still short but more pronounced. Crests do not break. When visibility good, horizon line always very clear.
||Wind felt on face. Leaves rustle. Ordinary vane moved by wind.
||12 - 19
||7 - 10
||Large wavelets. Crests begin to break. Foam of glassy appearance. Perhaps scattered whitecaps.
||Leaves and small twigs in constant motion. Wind extends light flag.
||20 - 28
||11 - 16
||Small waves, becoming longer. Fairly frequent whitecaps.
||Raises dust and loose paper. Small branches are moved.
||29 - 38
||17 - 21
||Moderate waves, taking a more pronounced long form. Many whitecaps are formed. Chance of some spray.
||Small trees with leaves begin to sway. Crested wavelets form on inland waters.
||39 - 49
||22 - 27
||Large waves begin to form. The white foam crests are more extensive everywhere. Probably some spray.
||Large branches in motion. Whistling heard in telephone wires. Umbrellas used with difficulty.
||50 - 61
||28 - 33
||Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind.
||Whole trees in motion. Inconvenience felt in walking against wind.
||62 - 74
||34 - 40
||Moderately high waves of greater length. Edges of crests begin to break into the spindrift. The foam is blown in well-marked streaks along the direction of the wind.
||Breaks twigs off trees. Generally impedes progress. Walking into wind almost impossible.
||75 - 88
||41 - 47
||High waves. Dense streaks of foam along the direction of the wind. Crests of waves begin to topple, tumble and roll over. Spray may affect visibility.
||Slight structural damage occurs, e.g. roofing shingles may become loose or blow off.
||89 - 102
||48 - 55
||Very high waves with long overhanging crests. Dense white streaks of foam. Surface of the sea takes a white appearance. The tumbling of the sea becomes heavy and shock-like. Visibility affected.
||Trees uprooted. Considerable structural damage occurs.
||103 - 117
||56 - 63
||Exceptionally high waves. Sea completely covered with long white patches of foam. Visibility affected.
||118 - 133
||64 - 71
||Air filled with foam and spray. Sea entirely white with foam. Visibility seriously impaired.
||Rare. Severe widespread damage to vegetation and significant structural damage possible.