This loop of GOES-9 visible imagery shows a Catalina Eddy circulation just off the southern California coast. This eddy intensified on 16 June and acted to induce a persistent onshore flow of marine air into the coastal counties. Hourly surface wind reports (red) are plotted on each image, and the ETA 1000 hPa wind streamlines (6-hour forecast) is plotted on the 17:45 UTC image (black). The ETA model did not have a good handle on the intensification of this mesoscale eddy feature.