Cyclone Ami was born in south Pacific waters as part of a vigorous "twin cyclone" system straddling the equator. Twin cyclones are occasionally spawned by the Tropical Intraseasonal Oscillation as it moves eastward out of the Indian Ocean and toward the International Dateline. This image of the central Pacific shows the rain accumulation from these two cyclones. The long trail of heavy rain oriented from north to south was produced by Cyclone Ami. The northern vortex of the pair, yet to be assigned an official name, was being monitored for development as it moves into the open waters of the northwestern Pacific.
This TRMM image and those of other extreme events can be found at the TRMM website trmm.gsfc.nasa.gov.