Wind Speed (mph)
0 5 10 15 20 25 30 35 40 45 50 55 60
25°F 19°F 15°F 13°F 11°F 9°F 8°F 7°F 6°F 5°F 4°F 4°F 3°F
20°F 13°F 9°F 6°F 4°F 3°F 1°F 0°F 1°F 2°F 3°F 3°F 4°F
15°F 7°F 3°F 0°F 2°F 4°F 5°F 7°F 8°F 9°F 10°F11°F 11°F
10°F 1°F 4°F 7°F 9°F 11°F12°F 14°F 15°F 16°F 17°F18°F 19°F
5°F 5°F10°F13°F15°F17°F19°F 21°F 22°F 23°F24°F25°F 26°F
0°F 11°F16°F19°F22°F24°F 26°F 27°F 29°F 30°F31°F32°F 33°F
5°F 16°F22°F26°F29°F31°F 33°F 34°F 36°F37°F38°F39°F 40°F
10°F22°F28°F32°F35°F 37°F 39°F 41°F 43°F44°F45°F46°F 48°F
15°F28°F35°F39°F42°F 44°F 46°F 48°F 50°F51°F52°F54°F 55°F
20°F34°F41°F45°F48°F 51°F 53°F 55 57°F58°F60°F61°F 62°F
25°F40°F47°F51°F 55°F 58°F 60°F 62°F64°F65°F67°F68°F 69°F
30°F46°F53°F58°F 61°F 64°F 67°F 69°F71°F72°F74°F75°F 76°F
35°F52°F59°F64°F 68°F 71°F 73°F76°F78°F79°F81°F 82°F 84°F
40°F57°F66°F 71°F 74°F 78°F 80°F82°F84°F86°F88°F 89°F 91°F
45°F63°F72°F 77°F 81°F 84°F 87°F89°F91°F93°F95°F 97°F 98°FWhat are the major scalesused in interpreting hurricanes and tornadoes?
There are two major scales used to interpret hurricane and tornado intensity—and
thus potential damage. The Saffir-Simpson Hurricane Damage-Potential Scaleis a
hurricane force scale using the numbers 1 through 5 to rate a hurricane’s intensity.
The scale was developed by engineer Herbert Saffir (1917–) and pioneer hurricane
expert Robert Simpson (1912–) in 1971. A number on the scale is assigned to a hurri-
cane based on its peak wind speed; it is also used to give an estimate of the potential
property damage and flooding expected along the coast from a hurricane landfall.Saffir-Simpson Hurricane Scale
Category Wind Strength Pressure (mb) Effects
1 74-95 mph >980 mb Oceans surge 4 to 5 feet above normal; minimal
(119-153 kph; damage; some bushes and trees lightly
65-83 knots) damaged; unanchored mobile homes may shift;
some coastal flooding and pier damage
2 96-110 mph 980-965 mb Waters surge 6 to 8 feet above normal;
(154-177 kph; considerable vegetation damage; some door,
84-95 knots) window, and roof damage; mobile homes and
poorly built piers receive significant damage;
coastal and low-lying areas flood from 2 to 4
310 hours before center hurricane reaches shore