Tropical cyclones in 1998
A total of 125 tropical cyclones formed, with 72 of them being named by various weather agencies when they attained maximum sustained winds of 35 knots (65 km/h, 40 mph).
The accumulated cyclone energy (ACE) index for the 1998 (seven basins combined), as calculated by Colorado State University was 773.1 units.
[2] The season had above average activity, due to the dissipation of the El Niño event and transition to La Niña conditions.
Georges devastated Saint Kitts and Nevis, Puerto Rico and the Dominican Republic as a major Category 3 storm but peaked as a high-end Category 4 hurricane just before moving through many of the Caribbean Islands before affecting the southern US mainland, making its landfall near Biloxi, Mississippi, causing significant damage and at least 600 confirmed deaths while Mitch, the strongest storm of the season, was a very powerful and destructive late-season Category 5 hurricane that affected much of Central America before making landfall in Florida as a tropical storm.
The ITCZ, which is normally situated south of the Gulf of Tehuantepec, shifted northward into Central and Southern Mexico, making the cyclone closer to cooler sea surface temperatures, hence limiting the number of storms that formed during the season.
The first tropical cyclone developed on May 28, marking the fourth latest start to any Pacific typhoon season on record, and the last one dissipated on December 22.
The Philippine region also set a record: with only eleven storms forming or moving into its area of responsibility, PAGASA had its quietest season as of 2006.
[5] Overall inactivity was caused by an unusually strong La Niña, which also fueled a hyperactive Atlantic hurricane season that year.
Over 10,000 people were killed in India when Tropical Cyclone 03A brought a 4.9-metre (16 ft) storm surge to the Kathiawar Peninsula, inundating numerous salt mines.
The first tropical disturbance originated on January 16, although the first named storm, Anacelle, was not upgraded until February 8, a record late start.
Many of the storms suffered from the effects of wind shear, which contributed to there being only one tropical cyclone – equivalent to a minimal hurricane.
Although Anacelle was the first named storm of the season, another tropical depression preceded it that crossed Madagascar several times.
The first system of the season proper originated out of an area of convection in early September in the northeast portion of the basin.
The system tracked westward, and the JTWC issued a Tropical Cyclone Formation Alert (TCFA) on September 4.
Later in the month, Tropical Disturbance A2 formed in a similar region within the monsoon trough, with the MFR initiating advisories on September 29.
[7] That day, the JTWC upgraded the system to tropical storm status,[8] although strong wind shear prevented intensification.
The MFR quickly discontinued advisories, but the JTWC continued tracking it, again upgrading the system to tropical storm status on October 1.
A month later, Alison developed over the open waters near Western Australia, peaking as a severe tropical cyclone before passing near Cocos Islands, bringing gale-force winds before dissipating on 13 November, shortly before crossing to the South-West Indian Ocean basin.
However, due to uncertainties in the continuation of Tui after several other weak low-pressure areas had formed, the FMS decided to treat the cyclone as a separate system and named it Wes.
[13] Tropical Cyclone Bart developed during the final days of the season and caused ten deaths and minor damage to French Polynesia, before it dissipated during May 3.
The first, Tropical Disturbance 01F, developed about 540 km (340 mi) to the northwest of Apia in American Samoa, however, the system remained weak and was last noted later that day.
On December 11, the JTWC started to monitor an area of disturbed weather that had developed within a trough of low pressure, about 670 km (415 mi) to the northeast of Honiara in the Solomon Islands.
On December 25, Tropical Disturbance 04F developed over the Coral Sea within an area of strong vertical wind shear in the Australian region.
