question about hurricane categories

[Deputy Van Halen]

I was wondering something about the categories that measure hurricane intensity. When deciding what category the storm falls into, do they consider just the circulation winds, or the winds on the ground?

For example, a storm has circulation winds of 105mph, which would make it a Cat2. But it is traveling at 15mph, which means that to the right side of the eyewall, the people on the ground are experiencing 120mph winds, which makes it a Cat3.

I'm guessing it is the latter, but I haven't seen the question directly addressed in the hurricane literature I've read.

[wxmann_91]

The max sustained winds are simply...the max sustained winds. If a hurricane's 115 mph it is only that in the strongest portion of the storm. So, for example, if it's traveling at 15 mph, on the left side it would only be 85 mph.

Hope it clears things up.

[caneflyer]

The max sustained winds are simply...the max sustained winds. If a hurricane's 115 mph it is only that in the strongest portion of the storm. So, for example, if it's traveling at 15 mph, on the left side it would only be 85 mph.

Hope it clears things up.

Yes, the max winds are the max winds, and they refer to the actual wind at the 10 m level, but you can't add (or subtract) the storm motion to deduce what the winds in one part of the storm are relative to the winds in another part. It doesn't work that way. Yes, the winds on the left side are generally lower than the right, but not always, and certainly not always lower by 2*(forward speed). Too many other factors are involved, including the shear of the environmental (steering) flow, and convective asymmetries.