Detailed observations of dow through large arrays of flat plates are used with mass transfer experiments to explore the convective behavior in offset-strip geometries. Unique local data for individual plates in the array are obtained using the naphthalene sublimation technique. With the flow visualization results, these local data reveal the effects of boundary-layer growth and vortex shedding in the array. Row-by-row data are used to determine the onset of shedding within the array. Surface average results are presented and show the relative contributions to heat transfer of boundary-layer restarting and vortex shedding.