Here’s a quick plot from one of Sounder’s laps around the inshore box today (14 Sep 2017). The first leg goes along the 20 m isobath from the NW corner to the southwest corner. The upper 10 m of water is headed onshore (red) at ~20 cm/s, and the lower 10 m of water is headed offshore at ~ 20 cm/s. Classic cross-shore exchange? You be the judge. More puzzling is the lack of exchange (or much flow at all, green being ~0 cm/s) along the 10 m isobath….