Fujita Scale for Damaging Winds 

Scale Category    MPH   Expected Damage 

F0    Weak      40-72   Light. Tree branches broken, signs damaged 
F1    Weak     73-112   Moderate. Trees snapped, windows broken 
F2    Strong  113-157   Considerable. Large trees uprooted, weak 
                        structures destroyed 
F3    Strong  158-206   Severe. Trees leveled, cars overturned, walls 
                        removed from buildings 
F4    Violent 207-260   Devastating. Frame houses destroyed 
F5    Violent 261-318   Incredible. Structures the size of autos moved 
                        over 100 miles, steel-reinforced buildings 
                        highly damaged.