sentences:  During April 21, the disturbance moved towards the southwest and affected Niue while starting to rapidly weaken, before it was last noted during April 22 wrapping into Cyclone Shelia's circulation.Tropical Depression 17F then developed on April 26 while located about to the northeast of Pago-Pago in American Samoa.During April 29, Tropical Depression 18F developed within a monsoon trough about , to the northeast of Suva, Fiji.