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Fujita Scale - Scale used to estimate the wind speed of tornadoes based on the tornado's destructive characteristics. Beaufort Scale - Scale used to measure wind speed. Based on the effects of the wind on land and in the sea. Saffir-Simpson Scale - Scale used to categorize hurricanes. Hailstone Category Scale - Scale used by meteorologists to determine approximate hailstone sizes. |
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Fujita Scale |
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Tornado Rating |
Tornado Name |
Wind Speeds (mph) |
Damage |
|
F0 |
Gale Tornado |
40-72 |
Light damage. Some damage to chimneys; break branches off trees; push over shallow-rooted trees; damage sign boards. |
|
F1 |
Moderate Tornado |
73-112 |
Moderate damage. The lower limit is the beginning of hurricane wind speed; peel surface off roofs; mobile homes pushed off foundations or overturned; moving autos pushed off the roads. |
|
F2 |
Significant Tornado |
113-157 |
Considerable damage. Roofs torn off frame houses; mobile homes demolished; boxcars pushed over; large trees snapped or uprooted; light-object missiles generated. |
|
F3 |
Severe Tornado |
158-206 |
Severe damage. Roofs and some walls torn off well-constructed houses; trains overturned; most trees in forest uprooted; heavy cars lifted off the ground and thrown. |
|
F4 |
Devastating Tornado |
207-260 |
Devastating damage. Well-constructed houses leveled; structures with weak foundations blown off some distance; cars thrown and large missiles generated. |
|
F5 |
Incredible Tornado |
261-318 |
Incredible damage. Strong frame houses lifted off foundations and carried considerable distance to disintegrate; automobile sized missiles fly through the air in excess of 100 meters(109 yds); trees debarked; incredible phenomena will occur. |
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F6 |
(non-existing tornado) |
319 to March 1 |
Speed of sound... |
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Beaufort Scale |
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Beaufort Number |
Wind Speed (mph) |
Seaman's Term |
Effects at Sea |
Effects on Land |
0 |
Less than 1 |
Calm |
Sea like mirror. |
Calm; Smoke rises vertically. |
1 |
1-3 |
Light Air |
Ripples with appearance as fish scales; no foam crests. |
Smoke drift indicates wind direction; vanes do not move. |
2 |
4-7 |
Light Breeze |
Small wavelets; crests of glassy appearance not breaking. |
Wind felt on face; leaves rustle; vanes begin to move. |
3 |
8-12 |
Gentle Breeze |
Large wavelets; crests begin to break; scattered whitecaps. |
Leaves, small twigs in constant motion; light flags extended. |
4 |
13-18 |
Moderate Breeze |
Small waves; becoming longer; numerous whitecaps. |
Dust, leaves and loose paper raised up; small branches move. |
5 |
19-24 |
Fresh Breeze |
Moderate waves; becoming longer; many whitecaps; some spray. |
Small trees in leaf begin to sway. |
6 |
25-31 |
Strong Breeze |
Larger waves forming; whitecaps everywhere; more spray. |
Large branches of trees in motion; whistling heard in wires. |
7 |
32-38 |
Moderate Gale |
Sea heaps up; white foam from breaking waves begins to be blown in streaks. |
Whole trees in motion; resistance felt in walking against wind. |
8 |
39-46 |
Fresh Gale |
Moderately high waves of greater length; foam is blown in well-marked streaks. |
Twigs and small branches broken off trees. |
9 |
47-54 |
Strong Gale |
High waves, sea spray begins to roll; dense streaks of foam; spray may reduce visibility. |
Slight structual damage occurs; slate blown from roofs. |
10 |
55-63 |
Whole Gale |
Very high waves with overhanging crests; sea takes white appearance; visibility reduced. |
Seldom experienced on land; trees broken; structual damage occurs. |
11 |
64-72 |
Storm |
Exceptionally high waves; sea covered with white foam patches. |
Very rarely experienced on land; usually with widespread damage. |
12 |
73 + |
Hurricane Force |
Air filled with foam; sea completely white with driving spray; visibility greatly reduced. |
Violence and destruction. |
Saffir-Simpson Scale |
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Scale Number |
Central Millibars |
Pressure (inches) |
Windspeed (mph) |
Storm Surge (ft) |
Type |
1 |
> = 980 |
> = 28.94 |
74-95 |
4-5 |
Minimal |
2 |
965-979 |
28.5-28.91 |
96-110 |
6-8 |
Moderate |
3 |
945-964 |
27.91-28.47 |
111-130 |
9-12 |
Extensive |
4 |
920-944 |
27.17-27.88 |
131-155 |
13-18 |
Extreme |
5 |
< 920 |
< 27.17 |
155 + |
18 + |
Catastrophic |
Hailstone Category Scale |
|
Hailstone Description |
Hailstone Diameter (inches) |
Pea |
0.25 |
Marble |
0.50 |
Penny, Large Marble, Dime |
0.75 |
Mothball, Nickel |
0.88 |
Quarter |
1.00 |
Half Dollar |
1.25 |
Walnut |
1.50 |
Golf Ball |
1.75 |
Hen Egg |
2.00 |
Tennis Ball |
2.50 |
Baseball |
2.75 |
Tea Cup |
3.00 |
Grapefruit |
4.00 |
Softball |
4.50 |