In a survey of examples of formative tropical cyclones viewed by the TIROS satellite, and a comparison of many of these views with surface, upper-air, and time and space-section analyses, it is found that, the upper-level structure of the formative cyclone of moderate intensity is grossly similar to that of the storm at maturity. Common features in most examples studied include: (1) an upper-level trough or shear line which preceded the low-level trough and which moved with the storm system; and (2) an upper-level ridge or anticyclone which was generally superimposed over the convective area east of the lower-level trough or vortex. As has been found with the mature storm, strong subsidence occurred under the upper trough and coincided with a cloudiness minimum area in advance of the major convective cloudiness and west of the trough axis. Upward vertical motion with heavy convective activity was suggested under the upper-level ridge or anticyclone to the rear of the lower-level trough. Several e... Abstract In a survey of examples of formative tropical cyclones viewed by the TIROS satellite, and a comparison of many of these views with surface, upper-air, and time and space-section analyses, it is found that, the upper-level structure of the formative cyclone of moderate intensity is grossly similar to that of the storm at maturity. Common features in most examples studied include: (1) an upper-level trough or shear line which preceded the low-level trough and which moved with the storm system; and (2) an upper-level ridge or anticyclone which was generally superimposed over the convective area east of the lower-level trough or vortex. As has been found with the mature storm, strong subsidence occurred under the upper trough and coincided with a cloudiness minimum area in advance of the major convective cloudiness and west of the trough axis. Upward vertical motion with heavy convective activity was suggested under the upper-level ridge or anticyclone to the rear of the lower-level trough. Several e...