||0||Sea like a mirror||Calm. Smoke rises vertically.
||0–1||Ripples with the appearance of scales are formed, but without foam crests||Smoke drift indicates wind direction and wind vanes cease moving.
||1–2||Small wavelets, still short but more pronounced; crests have a glassy appearance and do not break||Wind felt on exposed skin. Leaves rustle and wind vanes begin to move.
||2–3.5||Large wavelet; crests begin to break; foam of glossy appearance; perhaps scattered white horses||Leaves and small twigs constantly moving, light flags extended.
||1–2||3.5–6||Small waves, becoming longer; fairly frequent white horses||Dust and loose paper raised. Small branches begin to move.
||2–3||6–9||Moderate waves, taking a more pronounced long form; many white horses are formed (chance of some spray)||Branches of a moderate size move. Small trees in leaf begin to sway.
||3–4||9–13||Large waves begin to form; the white foam crests are more extensive everywhere (probably some spray)||Large branches in motion. Whistling heard in overhead wires. Umbrella use becomes difficult. Empty plastic garbage cans tip over.
||13–19||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. Effort needed to walk against the wind.
||29–41||Moderately high waves of greater length; edges of crests begin to break into the spin drift; the foam is blown in well-marked streaks along the direction of the wind||Some twigs broken from trees. Cars veer on road. Progress on foot is seriously impeded.
||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||Some branches break off trees, and some small trees blow over. Construction/temporary signs and barricades blow over.
|10||Storm||89–102||55–63||48 – 55
||37–52||Very high waves with long overhanging crests; the resulting foam, in great patches, is blown in dense white steaks along the direction of the wind; on the whole, the surface of the sea takes a white appearance; the tumbling of the sea becomes heavy and shock-like; visibility affected||Trees are broken off or uprooted, saplings bent and deformed. Poorly attached asphalt shingles and shingles in poor condition peel off roofs.
≥ 14||Exceptionally high waves (small- and medium-sized ships might be for a time lost to view behind the waves); the sea is completely covered with long white patches of foam lying along the direction of the wind; everywhere the edges of the wave crests are blown into froth; visibility affected||Very widespread damage to vegetation. Some windows may break; mobile homes and poorly constructed sheds and barns are damaged. Debris may be hurled about.
||The air is filled with foam and spray; sea completely white with driving spray; visibility very seriously affected||