Radio-transmitted synoptic data are used to determine the change brought about in the thermal structure of the Atlantic Ocean by the passage of hurricane Betsy in 1965. Such data for sea surface temperature and bathythermograph observations are regularly available from selected areas. Although they are not highly accurate and their interpretation is difficult, they could be more widely utilized in synoptic oceanography, as in this example and in oceanographic forecasting. The data for Betsy indicate thermal changes in the sea similar to those described previously for hurricane Hilda where research data were used. They give evidence of upwelling from 200 ft near the storm track, a 4F sea surface temperature decrease, and downwelling farther away from the track.