Tropical storm scales

I confused everyone, including myself, in the last post because although I have a good handle on the definitional issues for tropical storms in the South Pacific I did not have as good of a handle on the definition of typhoons as I thought I did. That plus some sloppy editing on my part made things more confusing than they needed to be.

If you want to learn more about the various definitions Wikipedia does a pretty good job of comparing the various tropical storm scales in use by different agencies.

In short, besides the physical characteristics and geographical limitations imposed, from purely a wind speed definition, the most common definitions of cyclones start at >34 knots, and both hurricanes and typhoons at >64 knots.

Be careful however, as I learned, agencies vary in their usage of the term. The reports I was reading about typhoons were using >34 knots as their wind speed definition and so I inaccurately copied their term. In the Marshalls, >34 knots is where tropical storms start and so if I count all storms >34 knots I am including both tropical storms and typhoons. It’s a good definition to use to compare with the South Pacific cyclone data but is not an accurate definition of typhoon. I’ve edited the last post to try to make that somewhat more clear.

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