Sawmaster
Member
And the winds are measured differently too.Only the storm surge can cause true EF5 style damage. Wind damage can get around EF3 levels visually but it's obviously not as simple as a comparison as you might think,
For hurricanes it's the highest average speed measured over a 1 minute time span in 5MPH increments with gusts measured separately. In modern times speeds must be measured on an approved anemometer or by other proven scientific method to be considered 'official'.
For tornadoes it's the highest speed reached without consideration of gusts, and usually it's estimated based on damage. I'm not sure there's an agreement on how to measure, or how long to measure these winds when measurement is possible.
Cup-type anemometers such as were all we had till modern times have a built-in 'lag' due to the inertia of the rotor and generally need about 3 seconds to stabilize to get an accurate measurement. Recent studies show that most can't be relied on for best accuracy past about 125MPH due to the behavior of wind forces on the back of the cups. I mentiion this because almost all of our record-setting hurricanes in past times were,measured this way making accurate direct comparisons with recent hurricanes impossible.
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