Original from 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 / Stiltjebleke)
< 1 knot
< 1 mph
< 2 km/h
< 0.5 m/s
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. Gale pennant.svg
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. Gale pennant.svg
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. Gale pennant.svg
Gale pennant.svg
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). Gale pennant.svg
Gale pennant.svg
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. Storm warning.svg
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. Storm warning.svg
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. Storm warning.svg

Storm warning.svg