Activity across the southern hemisphere's three basins—South-West Indian, Australian, and South Pacific—was spread evenly, with each region recording seven named storms apiece.

The accumulated cyclone energy (ACE) index for the 2004 (seven basins combined), as calculated by Colorado State University was 1024.4 units.

The costliest tropical cyclone was Hurricane Ivan, which struck Caribbean and United States in September causing a tornado outbreak, with US$26.1 billion in damage.

The deadliest tropical cyclone of the year was Hurricane Jeanne who killed for at least 3,006 deaths in Haiti.

Due to a Modoki El Niño – a rare type of El Niño in which unfavorable conditions are produced over the eastern Pacific instead of the Atlantic basin due to warmer sea surface temperatures farther west along the equatorial Pacific – activity was above average in North Atlantic Ocean.

A total of 138 systems formed globally in the year with 60 of them causing significant damage, deaths, and/or setting records for their basin.