The position of the eye and the radius of maximum wind were 

 first determined. To account for the asymmetry of the wind fields, k 

 was determined by fitting the observed radial wind profiles along 

 different sectants around the eye. A total of 8 profiles was fitted 

 for each chart. Figure 9 shows sections where these profiles were 

 fitted. In each case, the profile was plotted by digitizing the 

 radial distance from the center to the isovels on the observed chart. 

 The maximum wind speed, Wjj,, was determined from the plot at the 

 distance R from the center. The radial wind profile was computed 

 from (73) by substituting R, Wjj, and assuming k=l. The resulting 

 profile was compared to the observed and k was adjusted to obtain the 

 best possible agreement. 



Prior to 1200 GMT 9 September, during which there were no 

 regional Carla surface wind charts, the analysis to obtain R, Wj^ and 

 k depended upon the surface pressure charts from the National 

 Climatic Center. Eq. 68 was rewritten, by using (71), as 



W = [(R/r)'^(k/p3)(Pj^-Pj,)e-^^/^)'' + (irf)2]2 _ ^j.f_ (75) 



The time sequence of the radius of maximum wind was extrapolated back 

 in time using its relation to the central pressure which is 

 summarized in NWS-23. The radial distances to those points where 

 observed winds were reported, were digitized from the surface chart. 

 The far field pressure was determined from the first cyclonically 

 curved isobar. Assuming p^ = 1.15 Kg/m-^ and k=l, the wind speed 

 computed from (75) was compared to the observed value and again k was 

 adjusted to obtain minimum error. Once k was determined, Wjj, was 



44 



