An F3 tornado is classified as a severe tornado with powerful wind speeds ranging from 158 to 206 miles per hour (mph). This intensity places it in the upper-middle range of the original Fujita Scale, indicating significant destructive capability.
Understanding the Fujita Scale Classification
The Fujita Scale (F-Scale), developed by Dr. Tetsuya Theodore Fujita, was historically used to classify tornadoes based on their wind speed and the damage they caused. While largely superseded by the Enhanced Fujita Scale (EF-Scale) since 2007, the F-Scale remains a foundational concept in meteorology and is often referenced. The scale categorizes tornadoes into six levels, from F0 to F5, with increasing intensity.
Here's how an F3 tornado fits into the original Fujita Scale:
| F-Scale Number | Intensity Phrase | Wind Speed |
|---|---|---|
| F1 | Moderate tornado | 73-112 mph |
| F2 | Significant tornado | 113-157 mph |
| F3 | Severe tornado | 158-206 mph |
| F4 | Devastating tornado | 207-260 mph |
| F5 | Incredible tornado | 261-318 mph |
Characteristics and Impact of an F3 Tornado
The "bigness" of an F3 tornado is primarily defined by its extreme intensity and the extensive damage it can inflict, rather than a fixed physical dimension. The high wind speeds associated with an F3 rating result in widespread devastation.
Destructive Potential
An F3 severe tornado is capable of causing substantial structural damage and significant alterations to the landscape. Typical damage associated with an F3 tornado includes:
- Structural Damage: Roofs and walls can be torn off well-constructed houses, leaving only interior walls or foundations. Entire stories of homes may be removed.
- Heavy Objects Moved: Trains can be overturned, and heavy cars can be lifted off the ground and thrown considerable distances.
- Vegetation Destruction: Most trees in forests are likely to be uprooted, snapped, or de-limbed, resembling a clear-cut area.
- Industrial Structures: Unreinforced masonry buildings or non-reinforced concrete block structures can be severely damaged or destroyed.
Physical Dimensions
While the Fujita Scale classifies intensity, not physical dimensions, F3 tornadoes are generally considered strong and often cover a significant area. The actual width of an F3 tornado's damage path can vary greatly, from tens of yards to over a mile wide, and its path length can extend for many miles. It's important to remember that these physical dimensions are not part of the F-scale classification itself but are common observations for tornadoes of this intensity.
The Evolution to the Enhanced Fujita Scale
For greater accuracy in damage assessment and more precise correlation with wind speeds, the United States transitioned from the Fujita Scale to the Enhanced Fujita (EF) Scale in 2007. The EF-Scale uses 28 damage indicators with varying degrees of damage (DOD) to estimate wind speeds more reliably. An EF3 tornado, while broadly similar in destructive power to an F3, has a slightly different wind speed range (136-165 mph) based on these refined damage assessments.
Understanding the F3 classification helps to grasp the sheer power and danger associated with these severe weather phenomena, highlighting the critical need for preparedness and early warning systems.
