ON THE WIND ASYMMETRY OF HURRICANES

Abstract

The difference in the wind speeds across hurricanes (from the ?dangerous? to the opposite semi-circle) is often greater than twice the speed of propagation of the storm. The traditional explanation of the speed asymmetry of such storms must, then, be regarded as only a partial one. A speed asymmetry (in the same sense) must exist in the wind field as seen by an observer moving with the storm. Simple reasoning in terms of non-fluence lines (loci of points of parallel flow) applied to the simple model of a hurricane, consisting of a cyclonic indraft point plus its associated hyperbolic point, leads to the expected asymmetry in the relative field of flow.