Wind

(2021)

old.jandp.biz/aqua/travis/windscaleinfo.php

Original from wikipedia.org Beaufort scale and slightly edited here for better fit into small screens.

See also swedeteam…,com/wind/ – with converter between m/s, mph, …

B=Beaufort number

B	Description	Wind speed	Wave height	Sea conditions	Land conditions	Sea state photo	Associated warning flag
0	Calm (Lugnt / Stiltje, bleke)	< 1 knot < 1 mph < 2 km/h < 0.5 m/s	0 ft 0 m	Sea like a mirror	Smoke rises vertically.
1	Light air (Svag vind / Nästan stiltje)	1–3 knots 1–3 mph 2–5 km/h 0.5–1.5 m/s	0–1 ft 0–0.3 m	Ripples with appearance of scales are formed, without foam crests	Direction shown by smoke drift but not by wind vanes.
2	Light breeze (Svag vind / Lätt (laber) bris)	4–6 knots 4–7 mph 6–11 km/h 1.6–3.3 m/s	1–2 ft 0.3–0.6 m	Small wavelets still short but more pronounced; crests have a glassy appearance but do not break	Wind felt on face; leaves rustle; wind vane moved by wind.
3	Gentle breeze (Måttlig vind / God bris)	7–10 knots 8–12 mph 12–19 km/h 3.4–5.5 m/s	2–4 ft 0.6–1.2 m	Large wavelets; crests begin to break; foam of glassy appearance; perhaps scattered white horses	Leaves and small twigs in constant motion; light flags extended.
4	Moderate breeze (Måttlig vind / Frisk bris)	11–16 knots 13–18 mph 20–28 km/h 5.5–7.9 m/s	3.5–6 ft 1–2 m	Small waves becoming longer; fairly frequent white horses	Raises dust and loose paper; small branches moved.
5	Fresh breeze (Frisk vind / Styv bris)	17–21 knots 19–24 mph 29–38 km/h 8–10.7 m/s	6–10 ft 2–3 m	Moderate waves taking a more pronounced long form; many white horses are formed; chance of some spray	Small trees in leaf begin to sway; crested wavelets form on inland waters.
6	Strong breeze (Frisk vind / Hård bris, frisk kuling/kultje)	22–27 knots 25–31 mph 39–49 km/h 10.8–13.8 m/s	9–13 ft 3–4 m	Large waves begin to form; the white foam crests are more extensive everywhere; probably some spray	Large branches in motion; whistling heard in telegraph wires; umbrellas used with difficulty.
7	High wind, moderate gale, near gale (Hård vind / Styv kuling/kultje)	28–33 knots 32–38 mph 50–61 km/h 13.9–17.1 m/s	13–19 ft 4–5.5 m	Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind; spindrift begins to be seen	Whole trees in motion; inconvenience felt when walking against the wind.
8	Gale, fresh gale (Hård vind / Hård kuling/kultje)	34–40 knots 39–46 mph 62–74 km/h 17.2–20.7 m/s	18–25 ft 5.5–7.5 m	Moderately high waves of greater length; edges of crests break into spindrift; foam is blown in well-marked streaks along the direction of the wind	Twigs break off trees; generally impedes progress.
9	Strong / severe gale (Mycket hård vind / Halv storm)	41–47 knots 47–54 mph 75–88 km/h 20.8–24.4 m/s	23–32 ft 7–10 m	High waves; dense streaks of foam along the direction of the wind; sea begins to roll; spray affects visibility	Slight structural damage (chimney pots and slates removed).
10	Storm, whole gale (Storm / Storm)	48–55 knots 55–63 mph 89–102 km/h 24.5–28.4 m/s	29–41 ft 9–12.5 m	Very high waves with long overhanging crests; resulting foam in great patches is blown in dense white streaks along the direction of the wind; on the whole the surface of the sea takes on a white appearance; rolling of the sea becomes heavy; visibility affected	Seldom experienced inland; trees uprooted; considerable structural damage.
11	Violent storm (Svår storm / Svår storm)	56–63 knots 64–72 mph 103–117 km/h 28.5–32.6 m/s	37–52 ft 11.5–16 m	Exceptionally high waves; small- and medium-sized ships might be for a long time lost to view behind the waves; sea is covered with long white patches of foam; everywhere the edges of the wave crests are blown into foam; visibility affected	Very rarely experienced; accompanied by widespread damage.
12	Hurricane force [7] (Orkan / Orkan)	≥64 knots ≥73 mph ≥118 km/h ≥32.7 m/s	≥46 ft ≥14 m	The air is filled with foam and spray; sea is completely white with driving spray; visibility very seriously affected	Devastation.