StormCast — Weather & Emergency Alerts

EF Scale Tornado Ratings
Explained

The Enhanced Fujita (EF) Scale rates tornadoes from EF0 to EF5 based on the damage they cause. It replaced the original Fujita Scale in 2007 and is used by the National Weather Service to classify every tornado in the United States.

How the EF Scale Works

Tornadoes are rated after they happen, not during. NWS survey teams examine the damage path and use 28 different Damage Indicators (buildings, trees, towers, etc.) to estimate the wind speed that caused the destruction. The tornado then gets an EF rating based on the highest estimated wind speed anywhere along its path.

This means a tornado's EF rating is a measure of what it did, not necessarily what its peak winds were at every moment. A tornado in open farmland may cause EF1-level damage even if its actual winds were stronger — there simply wasn't enough to damage to rate it higher.

The Ratings

0

EF0 — 65–85 mph

Light damage. Broken tree branches, shallow-rooted trees pushed over, damage to gutters and siding. Most tornadoes in the US are EF0.

1

EF1 — 86–110 mph

Moderate damage. Mobile homes overturned or destroyed. Roofs stripped, garage doors pushed in, large trees snapped. Moving vehicles pushed off roads.

2

EF2 — 111–135 mph

Considerable damage. Roofs torn off well-built homes. Mobile homes demolished. Large trees uprooted. Freight cars overturned. Objects become dangerous missiles.

3

EF3 — 136–165 mph

Severe damage. Entire stories of well-built houses destroyed. Heavy cars lifted and thrown. Structures with weak foundations blown away. Trees debarked.

4

EF4 — 166–200 mph

Devastating damage. Well-built homes completely leveled. Cars thrown long distances. Large structures sustain severe damage. These are rare — about 1% of all tornadoes.

5

EF5 — Over 200 mph

Incredible damage. Strong-frame houses swept clean off their foundations. Steel-reinforced concrete structures critically damaged. High-rise buildings sustain severe structural damage. Extremely rare — fewer than 1 per year on average.

Key Facts

Most Are Weak

About 77% of all tornadoes are EF0 or EF1. Only about 0.1% reach EF5.

Rated After the Fact

The NWS sends survey teams to examine damage. Ratings are assigned hours or days after the tornado, not during it.

Damage, Not Wind

The EF scale is based on damage indicators, not direct wind measurement. A tornado over open fields may appear weaker than it actually was.

Replaced the F-Scale in 2007

The Enhanced Fujita Scale improved on the original by using more damage indicators and better accounting for construction quality.

How to Get Tornado Alerts

StormCast delivers every NWS tornado warning, watch, and emergency directly to your Android phone within moments of being issued — before you even hear the sirens. The app checks the NWS feed every 30 seconds.

Get it on Google Play

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