Tornadoes: What is the Enhanced Fujita Scale?

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Tornadoes are common throughout the country and can occur at any time of the year. After a tornado occurs, it is assigned a rating ranging from EF-0 to EF-5 based on wind speed and estimated damage. For example, the brief tornado that caused minor damage in Boardman last weekend was rated EF-0.

National Weather Service (NWS) meteorologists used the Enhanced Fujita Scale to assign a rating to this tornado. What is the Enhanced Fujita Scale and what do these ratings mean?

What is the Enhanced Fujita Scale?

The Enhanced Fujita Scale (EF-Scale) replaced the Fujita Scale (F-Scale) in February 2007 and is used to assign a tornado a rating based on estimated wind speed and related damage.

According to the National Weather Service, the Enhanced Fujita Scale has been revised from the original Fujita Scale to reflect better reviews of tornado damage surveys to more closely align wind speeds with associated damage. to storms. The new scale has to do with how most structures are designed.

The EF scale takes into account more variables than the F scale, such as damage indicators (DI) and the eight degrees of damage (DOD). Damage indicators include building types, structures, and trees. Damage degrees are categorized by visible damage, minor damage, major damage, and complete destruction. The scale has 28 damage indicators and eight damage grades.

When surveying damage from the tornado, National Weather Service personnel will compare the damage to damage indicators and damage grades that help estimate the range of wind speeds the tornado likely produced, and then assign to the tornado a rating from EF-0 to EF. -5.

Tornadoes are assigned a rating of EF-0 to EF-5

What wind speeds and damage types are associated with EF-0 through EF-5 tornadoes?

An EF-0 tornado is generally considered a weak tornado with estimated wind speeds of 65-85 mph and is associated with minor damage. Examples of damage from an EF-0 tornado include damage to chimneys, broken tree limbs, and uprooted shallow-rooted trees.

An EF-1 tornado is generally considered a weak tornado, with estimated wind speeds of 86–110 mph, and is associated with moderate damage. Examples of damage from an EF-1 tornado include detached roof surfaces and mobile homes being pushed from their foundations or toppled.

An EF-2 tornado is generally considered a strong tornado with estimated wind speeds of 111-135 mph and is associated with extensive damage. Examples of damage caused by an EF-2 tornado include roofs ripped off homes, mobile homes demolished, large trees snapped or uprooted, and boxcars overturned.

An EF-3 tornado is generally considered a strong tornado with estimated wind speeds of 136-165 mph and is associated with severe damage. Examples of damage from an EF-3 tornado include roofs and walls torn from well-built homes, heavy cars being lifted and thrown, and most trees uprooted.

An EF-4 tornado is generally considered a violent tornado with estimated wind speeds of 166-200 mph and is associated with extreme damage. Examples of damage from an EF-4 tornado include leveled well-built homes, structures with weak blown foundations, and thrown cars.

An EF-5 tornado is generally considered a violent tornado with estimated wind speeds of over 200 mph and is associated with incredible damage. Examples of damage caused by an EF-5 tornado include sturdy frame homes lifted off the foundation and carried considerable distances and debarked trees.


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