Proudman Building, Liverpool weather station (original) (raw)

Wind speed conversion table (at 10 metres above ground)

Beaufort scale	Range of wind speeds	Mean wind speed
knots	m s−1	km h−1	miles h−1	knots	m s−1	km h−1	miles h−1
0	Calm	< 1	0.0 – 0.2	< 1	< 1	0	0.0	0	0
1	Light air	1 – 3	0.3 – 1.5	1 – 5	1 – 3	2	0.9	3	2
2	Light breeze	4 – 6	1.6 – 3.3	6 – 11	4 – 7	5	2.4	9	5
3	Gentle breeze	7 – 10	3.4 – 5.4	12 – 19	8 – 12	9	4.4	16	10
4	Moderate breeze	11 – 16	5.5 – 7.9	20 – 28	13 – 18	13	6.7	24	15
5	Fresh breeze	17 – 21	8.0 – 10.7	29 – 38	19 – 24	18	9.3	34	21
6	Strong breeze	22 – 27	10.8 – 13.8	39 – 49	25 – 31	24	12.3	44	28
7	Near gale	28 – 33	13.9 – 17.1	50 – 61	32 – 38	30	15.5	55	35
8	Gale	34 – 40	17.2 – 20.7	62 – 74	39 – 46	37	18.9	68	42
9	Strong gale	41 – 47	20.8 – 24.4	75 – 88	47 – 54	44	22.6	82	50
10	Storm	48 – 55	24.5 – 8.4	89 – 102	55 – 63	52	26.4	96	59
11	Violent Storm	56 – 63	28.5 – 32.6	103 – 117	64 – 72	60	30.5	110	68
12	Hurricane	64 – 71	32.7 – 36.9	118 – 133	73 – 82	68	34.8	125	78