Sea Surface Temperature (oC) from satellite (a) and HyCOM GoM (c) on July 19, 2018. The blue polygon is used as initial conditions for back-in-time trajectories to investigate the cool water pool's origin in the satellite data (a). Black dots in the right column are points from trajectories initiated within the blue polygon on July 19, 2018, and integrated back in time for 40 days (June 10, 2018) using HyCOM GoM's velocity at 5-m depth (b), and a 1994–2014 climatological velocity at the surface (d). Color contours in the right column are the velocity magnitude (ms-1) used for the trajectories after time averaging, HyCOM GoM at 5-m depth is shown in (b), and the velocity climatology at the surface is shown in (d). The blue line is used as a path representative of most of the trajectories shown in (b) and is plotted as a reference in the other panels. The 50-m isobath is shown in black. (Fig. \ref{256220}).