213 km/hr Tornado in Sydney, Australia.

[Trenno]

Seems like Sydney copped it this afternoon. News Article

From the photos, there have been numerous roof failures.

But what interests me... is that the recorded wind speed of 59 m/s is much higher than the code based V500 (3s gust) wind speed of 45 m/s. 31.5% higher.

 

[JAE]

The 213 km/hr is 132 mph. In the US, that is probably only an F2 tornado, which corresponds to the damage that shows in the link/photos.
Across the plains the FEMA design standard for tornadoes is 250 mph at the worst.

I don't know about Sidney, but typically building codes don't account for tornadoes.



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[hokie66]

Tornados do occur in Australia, but certainly not to the degree experienced in the US. The most common occurrences are as spawn of tropical cyclones, with the other type being as part of what the weather folks now call "supercell" thunderstorms. The latter type hit a small area of Sydney, and we had a similar one a few years ago in Brisbane. These supercells are common, but they mostly miss heavily populated areas because Australia is a big place. Because our wind requirements vary with area, Sydney is considered a low wind zone. Some of that is probably political, and probably needs reconsideration. Along the east cost, tropical cyclones are banned below about Bundaberg.

 

[msquared48]

A t least one in the Midwest has reached 300 mph if I remember correctly.

Mike McCann, PE, SE (WA)

 

[Compositepro]

"they mostly miss heavily populated areas because Australia is a big place" That used to be true of the U.S. (not that we have gotten smaller, just more populated).

 

[hokie66]

They still mostly miss heavily populated areas in the US, but when they do hit towns and cities, it is big news. Australia and the lower 48 are the same size, but Australia only has about 23 million people. But in terms of urbanization, Australia is more urban. We all herd together, which makes it harder to hit us, but when a storm does...