A meander structure of the North Atlantic Polar Front has been observed by satellite and towed undulating conductivity-temperature-depth probe (CTD) during the summer 1981. The high resolution of the CTD data allowed a comparison at the resolution of the satellite images (1.2 km). The average surface temperature differences of the independently calibrated CTD and satellite data were less than 0.2 k for those mixed-layer CTD data measured within 1 day of the satellite images. A strong decline of the temporal cross correlations between mixed-layer temperatures and sea surface temperature (SST) was observed shortly after the transition of an atmospheric front. A comparison of the SST with the isopycnic temperature distribution revealed the longer persistence of the structures in the stably stratified layers just beneath the mixed layer. The slow decline of the cross correlation between SST maps and the isopycnic temperature showed that the towed-fish survey was a synoptic measurement of the thermohaline field in seasonal thermocline. ¿ American Geophysical Union 1988