Figure 1: Ocean model fields for TCs (a,b) Sally, (c,d) Hanna, and (e,f)
Eta, showing changes in sea surface elevation over time (m/day,
shading), snapshots of instantaneous surface-current convergence
(s-1, dashed red contours), and 17.5
ms-1 (34 kt) surface wind fields (blue lines). Storm
forecast tracks are in brown with triangle markers every 6 h. The left
column shows a forecast hour prior to intensification: (a) hour 54, (c)
hour 18, (e) hour 108. Right column shows the forecast hour immediately
after intensification: (b) hour 66, (d) hour 24, (f) hour 114.