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During the field experiment phase of the Indian Ocean Experiment (INDOEX), linear cloud formations parallel to the West Indian coast and propagating westward have been observed. Meteosat‐5 images are used for the description of the life cycle of these events. Single cloud bands, or main cloud bands followed by (up to 10) secondary parallel cloud lines with a wavelike pattern, have been observed daily during four periods in the dry season of 1999 (15 January, 16–19 February, 27 February to 7 March, and 1–3 April 1999). During these four periods, one single cloud band or a packet of cloud bands is generated every day at nighttime. Their length reaches several hundreds of kilometers, their width lies below 40 km, and their duration in some cases exceeds 24 hours. The smaller cloud lines observed behind the leading cloud line are narrower and are separated by a distance of 2–10 km. Cloud tops are about 3–8°C colder than the Arabian Sea, corresponding to an altitude between 500 and 1200 m during the night and below 2500 m during daytime. Cloud bands travel westward over the Arabian Sea at a speed around 13 m/s, greater than the wind speed measured in the surrounding area. The motion of the cloud band presents similarities with the wavelike propagation of atmospheric phenomena such as the Australian morning glories. Common elements to the different cases are the following: weak low‐level winds close to the southwestern Indian coast when the cloud bands appear, winds with a northerly component in the vicinity of the northwestern Indian coast, the presence of a sea‐land breeze circulation along the West Indian coast, and the presence of high concentrations of pollutants over the northeastern Arabian Sea. However, existing physical links between these elements (if any) still have to be investigated.