Wind foce scale

 en.wikipedia.org

Historically, the Beaufort wind force scale provides an empirical description of wind speed based on observed sea conditions. Originally it was a 13-level scale, but during the 1940s, the scale was expanded to 17 levels.^[17] There are general terms that differentiate winds of different average speeds such as a breeze, a gale, a storm, tornado, or a hurricane. Within the Beaufort scale, gale-force winds lie between 28 knots (52 km/h) and 55 knots (102 km/h) with preceding adjectives such as moderate, fresh, strong, and whole used to differentiate the wind's strength within the gale category.^[18]

A storm has winds of 56 knots (104 km/h) to 63 knots (117 km/h).^[19] The terminology for tropical cyclones differs from one region to another globally. Most ocean basins use the average wind speed to determine the tropical cyclone's category. Below is a summary of the classifications used by Regional Specialized Meteorological Centers worldwide:

[hide]General wind classifications			Tropical cyclone classifications (all winds are 10-minute averages)
Beaufort scale[17]	10-minute sustained winds (knots)	General term[20]	N Indian Ocean IMD	SW Indian Ocean MF	Australian region South Pacific BoM, BMKG, FMS, MSNZ	NW Pacific JMA	NW Pacific JTWC	NE Pacific & N Atlantic NHC & CPHC
0	<1	Calm	Low Pressure Area	Tropical disturbance	Tropical low Tropical Depression	Tropical depression	Tropical depression	Tropical depression
1	1–3	Light air
2	4–6	Light breeze
3	7–10	Gentle breeze
4	11–16	Moderate breeze
5	17–21	Fresh breeze	Depression
6	22–27	Strong breeze
7	28–29	Moderate gale	Deep depression	Tropical depression
	30–33
8	34–40	Fresh gale	Cyclonic storm	Moderate tropical storm	Tropical cyclone (1)	Tropical storm	Tropical storm	Tropical storm
9	41–47	Strong gale
10	48–55	Whole gale	Severe cyclonic storm	Severe tropical storm	Tropical cyclone (2)	Severe tropical storm
11	56–63	Storm
12	64–72	Hurricane	Very severe cyclonic storm	Tropical cyclone	Severe tropical cyclone (3)	Typhoon	Typhoon	Hurricane (1)
13	73–85							Hurricane (2)
14	86–89				Severe tropical cyclone (4)			Major hurricane (3)
15	90–99			Intense tropical cyclone
16	100–106							Major hurricane (4)
17	107–114				Severe tropical cyclone (5)
	115–119			Very intense tropical cyclone			Super typhoon
	>120		Super cyclonic storm					Major hurricane (5)

Fujita scale

The Enhanced Fujita Scale (EF Scale) rates the strength of tornadoes in the United States based on the damage they cause. Below is that scale.

Scale	Wind speed		Relative frequency	Potential damage
	mph	km/h
EF0	65–85	105–137	53.5%	Minor or no damage. Peels surface off some roofs; some damage to gutters or siding; branches broken off trees; shallow-rooted trees pushed over. Confirmed tornadoes with no reported damage (i.e., those that remain in open fields) are always rated EF0.
EF1	86–110	138–178	31.6%	Moderate damage. Roofs severely stripped; mobile homes overturned or badly damaged; loss of exterior doors; windows and other glass broken.
EF2	111–135	179–218	10.7%	Considerable damage. Roofs torn off well-constructed houses; foundations of frame homes shifted; mobile homes completely destroyed; large trees snapped or uprooted; light-object missiles generated; cars lifted off ground.
EF3	136–165	219–266	3.4%	Severe damage. Entire stories of well-constructed houses destroyed; severe damage to large buildings such as shopping malls; trains overturned; trees debarked; heavy cars lifted off the ground and thrown; structures with weak foundations are badly damaged.
EF4	166–200	267–322	0.7%	Extreme damage. Well-constructed and whole frame houses completely leveled; cars and other large objects thrown and small missiles generated.
EF5	>200	>322	<0.1%	Total Destruction. Strong-framed, well-built houses leveled off and foundations swept away; steel-reinforced concrete structures are critically damaged; tall buildings collapse or have severe structural deformations.