Tropical Storm Greg (1996)

Greg was one of only three systems to made landfall in Malaysia, before Vamei in 2001 did so, nearly five years later, and Senyar in 2025 before crossing Western Pacific. The storm brought extensive and catastrophic damages across Sabah, causing over $280 million in damage (1996 USD) and 238 deaths, which mainly are foreigners and tourists. Another 102 individuals were also rendered missing. Flash floods and widespread mudslides were also recorded throughout the state, destroying houses and overflowing rivers, respectively.

Following the massive aftermath of the storm, the state government of Sabah immediately started to rehabilitate the areas that sustained damages, and relief operations were speeded. The government also allocated over $2 million for the operation process, while a relief fund collected $1 million for the affected evacuees. Mass graves were also started for the unidentifiable victims of the storm. Some authorities described Greg as one of the worst disasters in the history of Malaysia.

Meteorological history

In the middle of December, two low-latitude monsoon troughs were located in the extreme western Pacific Ocean, well associated with a strong westerly wind burst that would spawn the system that would be Tropical Storm Fern and itself in the Northern Hemisphere. The second trough which was located in the Southern Hemisphere, will also generate cloudiness in the Australian region that would also spawn three systems in the basin: namely Ophelia, Phil and Fergus. A persistent area of convection was first mentioned by the JTWC on December 21 at 2100 UTC in their Significant Tropical Weather Advisory over the low latitudes of the South China Sea, well west of Brunei. Two days later, the organization of the system became well-defined, as stated in their advisories on December 23 and in reports by weather stations in East Malaysia. In addition, the system's convection improved within the next 24 hours due to the active wind burst. At 04:00 UTC, the JTWC issued a Tropical Cyclone Formation Alert on the system, depicting a rapid convective organization being detected in the microwave and visible satellite images. Upper-level divergence on the system also began to be seen in water-vapor imagery, also a sign of tropical cyclogenesis. This was followed by the first warning by the agency on the system as Tropical Depression 43W, roughly two hours later. Despite wind shear starting to impact the developing system, the depression intensified to a tropical storm on December 25 at 0000 UTC and was named Greg. In post-tropical analysis, Greg may have likely intensified with gale-force winds, six hours later. Combined effects of wind shear and the prevailing northeast monsoon made Greg slowly intensify while taking a southeastward track, before turning to the east, approaching northwestern Sabah, a state of Malaysia. The forward motion of Greg also increased, before reaching its peak intensity of 85 km/h (55 mph) and a minimum barometric pressure reading of 1002 hPa (29.59 inHg) that time. It held this intensity until it made landfall along the town of Kudat between 1700 and 1800 UTC that day (03:00 and 04:00 am the next day, MYT) before hitting the major city of Sandakan, also that time. These landfalls weakened Greg to a tropical depression as it entered Sulu Sea before passing through Tawi-Tawi on December 26. It then entered the Celebes Sea on the afternoon of the same day before degenerating to a remnant low, shortly after as it encountered an unfavorable environment, namely colder sea surface temperatures. At 0600 UTC on December 27, the JTWC issued their final warning on the system as it dissipated to the south of Mindanao, ending the very active 1996 Pacific typhoon season.

The Joint Typhoon Warning Center tracked and named the system; however, the Japan Meteorological Agency did not included Greg in their annual best track.

Unusual formation

Tropical cyclones making landfall in Malaysia are extremely rare. Only Greg, Vamei of 2001, and Senyar of 2025 had only significant effects in the country, since reliable records began.

The east-southeastward movement of Greg is also unusual. Any tropical cyclone that forms and moves through the South China Sea will typically progress through the Indochina, became quasi-stationary, or move southwestward and dissipate immediately. This is due to the well-established northeasterly wind flow from the Northern Hemisphere. As Greg's predecessor formed in the waters near Vietnam, an unusually large wind pattern started to dominate the area where the system is and two low-level westerly winds existed from the north and south of the equator: namely the Northern and Southern Hemispheres. With these factors blocking the northeast monsoon to the east, the strong pattern of winds from the south helped Greg to take an eastward track. Adding on, the large circulation of developing Fern to its northeast were hypothesized as another reason for the system's east-southeastward motion as it started to dissipate.