This study leverages satellite observation and an existing semi-Lagrangian analysis framework to investigate the downstream impact of mesoscale sea surface temperature anomalies (SSTAs) in the northwest tropical Atlantic on the mesoscale aggregation of shallow cumulus convection. In our previous work using an Eulerian framework, we found that trade cumulus generation frequency and hence near-cloud-base cloudiness are locally enhanced over warm SSTAs due to enhanced surface fluxes and buoyancy-driven convective turbulence. The opposite response is found over cold SSTAs (i.e., symmetric). We hence hypothesize that local condensation heating anomalies induced by mesoscale sea surface temperature anomalies (SSTAs) can impact convective aggregation downwind via an inherent convective instability (a form of gross moist instability) in non-precipitating shallow cumulus. We use available satellite data from 7 winter seasons (2018-2024) for this semi-Lagrangian analysis. First, Lagrangian cloud trajectories are initiated over the daily centroids of warm and cold mesoscale SSTAs (identified from the NOAA GOES-POES blended SST analysis) and the designed reference locations (|SSTA|<0.1K) at different local times. These trajectories extend 12 hours backward and 18 hours forward in time from the origin using ERA5 wind fields at 925 hPa. Hourly cloud characteristic metrics are computed along the trajectories using shallow cumulus cloud masks derived from the NASA SatCORPS CERES GEO Edition 4 GOES-16 Northern Hemisphere V1.2 product. Preliminary results show that 1) downstream cloud response to SSTAs is modulated by the diurnal cycle of insolation and that 2) downstream cloud response to warm SSTAs tends to be stronger than that to cold SSTAs (i.e., asymmetric). Specifically, when coherent warm SSTAs are encountered at midnight (01:30LT) and early morning (7:30LT), trade cumulus cloud fraction, mean length scale of cloud objects, and the number of cloud objects all increase downstream within 12 hours, while the mean void size reduces. Further interpretation of the results is underway and will hopefully help understand the role of mesoscale SSTA and surface buoyancy flux anomalies in shallow cumulus convective aggregation.