Severe Tropical Storm Eliakim was a tropical cyclone that affected Madagascar and killed 21 people in 2018. The seventh tropical depression, sixth tropical storm of the 2017–18 South-West Indian Ocean cyclone season, and fourth tropical cyclone in 2018 to impact Madagascar, Eliakim was first noted as an area of atmospheric convection south-southwest of Diego Garcia on 9 March. Developmental conditions were favorable in its vicinity, and on 14 March, both the Joint Typhoon Warning Center (JTWC) and Météo-France La Réunion (MFR) began issuing warnings on the system, with MFR designating it as Tropical Disturbance 7 and the JTWC giving it the designation 14S. On the next day, MFR upgraded the system to a moderate tropical storm, assigning it the name Eliakim. Eliakim further intensified into a severe tropical storm on 15 March, with the JTWC upgrading it to a Category 1-equivalent cyclone on the Saffir–Simpson scale on 16 March. Eliakim made landfall on Masoala at 07:00 UTC, after which MFR estimated maximum 10-minute sustained winds of within the system. Eliakim weakened into a moderate tropical storm before abruptly turning southwards and re-emerging over water on 17 March. Despite unfavorable conditions, Eliakim re-intensified into a severe tropical storm on 19 March before being downgraded back into a moderate tropical storm 6 hours later. Eliakim transitioned into a post-tropical cyclone on 20 March as it moved away from Madagascar, with the MFR last tracking the system on 22 March.
The storm's outer bands first reached Madagascar on 15 March, and by 16 March, Eliakim made landfall on Madagascar. Thousands of people were evacuated in vulnerable areas, accompanied by advisories of heavy rainfall and strong winds. Flooding and heavy rainfall were observed in several regions, with a maximum of of rain being recorded in Île Sainte-Marie. Eliakim caused 21 fatalities in Madagascar, affected another 60,000, and displaced 19,439 people. Structures were also affected, with 17,228 homes, 15 roads, 27 health facilities, and 1,118 classrooms experiencing damage. Rehabilitation works in the country were estimated to cost 10 billion Malagasy ariary (US$3.21 million). Other countries also sustained impacts, with Réunion receiving swells of and parts of Kenya experiencing flooding.
Meteorological history
On 9 March at 10:30 UTC, the Joint Typhoon Warning Center (JTWC) began monitoring an area of atmospheric convection located approximately south-southwest of Diego Garcia, assessing its development potential within the next day as low. Convection was disorganized, and conditions were marginally favorable due to a beneficial upper-level environment and strong wind shear at , with sea surface temperatures in the area reaching . Météo-France La Réunion (MFR) began monitoring the area on the next day at 12:00 UTC, assessing its risk of developing into a tropical cyclone within the next 5 days as moderate. By 11 March, MFR further upgraded the system's risk of developing into a tropical cyclone within the next 5 days to high. An advanced scatterometer pass on 12 March at 06:05 UTC showed an elongated low-level circulation, and at 18:00 UTC, the JTWC upgraded the system's development potential within the next day to medium as wind shear decreased to . On 14 March at 00:00 UTC, MFR upgraded the system to a tropical disturbance, designating it as Tropical Disturbance 7. The JTWC assessed that it had developed into a tropical depression at the same time, giving it the designation 14S. Wind shear further decreased to , and as the system continued to consolidate and organize, MFR upgraded 7 to a tropical depression on 14 March at 12:00 UTC, though the system's internal structure remained broad.