Throughout the season, sea surface temperatures within the western equatorial Pacific were above normal, including those in the South China Sea. Areas of convection persisted year-round in the lower latitudes, particularly around the Philippines. Atmospheric divergence was also prevalent in the same regions, resulting in enhanced tropical cyclogenesis east of the Philippines in 2003; the mean region of development of tropical systems during the year was more southwest than the 1971–2000 30-year average. In 2003, the JMA monitored 21 tropical cyclones of at least tropical storm intensity; of those, 14 reached typhoon intensity. Though the number of tropical storms was below average, the ratio between tropical storms and typhoons was 66% greater than normal. The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) monitored three additional cyclones of at least tropical storm intensity that were not monitored by the JMA.