Timeline of the 2004 Pacific hurricane season

The 2004 Pacific hurricane season had 17 tropical cyclones, of which 12 became named storms, 6 became hurricanes, and 3 became major hurricanes (Category 3 or higher).[1][2] This timeline documents all the storm formations, strengthening, weakening, landfalls, extratropical transitions, as well as dissipation. It also includes information which was not operationally released, meaning that information from post-storm reviews by the National Hurricane Center, such as information on a storm that was not operationally warned on, have been included. The season officially began on May 15, 2004 in the eastern Pacific proper (June 1, 2004 in the central Pacific) and lasted until November 30 that same year.[3] Areas east of 140°W are under the purview of the National Hurricane Center (NHC); the area between the International Date Line and 140°W, or the central Pacific, is under the purview of the Central Pacific Hurricane Center (CPHC).

Track map of all storms during the season

The 2004 season got off to an early start with Tropical Storm Agatha, which formed a week after the season began.[4] No tropical cyclones were active in June, the first such occurrence since 1969.[5] July was more active, producing four tropical cyclones. Three of these (Blas, Celia, and Darby) became named storms, two (Celia and Darby) became hurricanes, and Hurricane Darby became the first major hurricane of the season.[6] Additionally, a tropical depression in the central Pacific became the only tropical cyclone to form within the Central Pacific Hurricane Center's area of responsibility during the year.[1] August was the most active month, producing six tropical cyclones, four named storms, and two hurricanes (Frank and Howard).[7] September saw a decline in activity, although all three storms that existed during the month were hurricanes, two of which (Howard and Javier) were major hurricanes. Hurricane Howard, which had formed in August, only became a major hurricane in September. Hurricane Javier – the final storm during the month – was the strongest storm of the season.[8] October saw the final three tropical cyclones of the year; two developed into named storms (Kay and Lester). Neither of these storms became hurricanes.[9]