Franklin Fact Archive
Back to Franklin Facts homepage.
Back to TV12
WEDNESDAY SEPTEMBER 6 - SAFFIR/SIMPSON SCALE OF HURRICANE INTENSITY
To measure a hurricane's intensity, meteorologists use what's called the
Saffir-Simpson Scale. The scale was devised in the
early 1970s by Herbert
Saffir, a consulting engineer, and Robert Simpson, then the director of the
National Hurricane Center. They combined structural engineering and meteorology
to quantify the level of damage to expect from a hurricane.
A tropical storm becomes a hurricane when its winds reach 74 mph, and that's when
the Saffir-Simpson scale kicks in. The scale runs from 1 to 5, with 1 being a
minimal hurricane and 5 the strongest. Meteorologists call these rankings "categories."
Categories 3, 4, and 5 are called major hurricanes, and they have the potential to
inflict extensive damage. Only two hurricanes on record have ever made landfall in
the United States with Category 5 intensity: Camille in 1969 and a hurricane that
struck the Florida Keys on Labor Day in 1935.