Earlier investigations of the diurnal and semidiurnal rainfall variations are extended with an analysis of hourly rainfall data at 735 stations in the United States and Puerto Rico. Interesting findings include a confirmation of the remarkable tendency (observed earlier by Lindzen (1978) and Hamilton (1981)) for the semidiurnal component of tropical rainfall to peak at roughly 0330 (and 1530) LT. It also appears that (at least over the United States) this 0330 phase (or one slightly later) is quite typical of the midlatitude region as well. The significance of these findings for the theory of the semidiurnal atmospheric tide is discussed.