Cyclone Fantala

While near peak intensity, Fantala passed near the Farquhar Group of the Seychelles, damaging most of the buildings in the small archipelago. Later on 18 April, Fantala had weakened to an intense tropical cyclone and slowed its forward motion, eventually reversing its direction of movement. After fluctuating in strength, the disorganized system reversed direction again, making its closest approach to Madagascar. Fantala degenerated into a remnant low on 24 April, and the remnants continued toward Tanzania. There, heavy rainfall resulted in flooding that washed away roads and houses, killing 13 people. Rains extended further into Kenya, with similar effects.

Meteorological history

On 9 April, an area of disturbed weather persisted to the southeast of Diego Garcia. The system moved generally westward, steered by a ridge, and a low-level circulation gradually became more defined. Limiting factors to faster development included poor inflow and moderate wind shear, although associated convection became more organized. At 06:00 UTC on 11 April, the Regional Specialized Meteorological Center Météo-France in La Réunion (MFR) classified the system as Tropical Disturbance 8 about 600 km (370 mi) south of Diego Garcia. Six hours later, the agency upgraded the system to a tropical depression. At 13:00 UTC on 11 April, the American-based Joint Typhoon Warning Center (JTWC) issued a tropical cyclone formation alert, noting the increased organization of the convection, circulation, and outflow. Later that day, the MFR upgraded the depression to Moderate Tropical Storm Fantala, and the JTWC classified it as Tropical Cyclone 19S. By that time, the convection was quickly consolidating around the center, organizing into a circular central dense overcast.

On 12 April, the previously detrimental wind shear began easing, allowing the structure to become more symmetric. On that day, an eye feature began developing in the center of Fantala, indicative of strengthening. At 12:00 UTC on 12 April, the MFR upgraded Fantala to severe tropical storm status, and six hours later, the JTWC upgraded it to the equivalent of a minimal hurricane, with 1 minute maximum sustained winds of 120 km/h (75 mph); rapid strengthening was prevented by the entrainment of nearby dry air, although the core of convection continued to contract. At 06:00 UTC on 13 April, the MFR upgraded Fantala to tropical cyclone status, with 10 minute winds of 130 km/h (80 mph). By that time, the eye feature persisted, consisting of a warm area within the deepest convection, although the dry air in the region prevented quicker strengthening.

By early on 14 April, the eye became better defined after an eyewall replacement cycle. The intensity fluctuated after outflow decreased to the north, although increasingly warm waters favored further intensification. Early on 15 April, the MFR upgraded Fantala to an intense tropical cyclone, as the storm rapidly deepened. The outflow was enhanced by a large upper-level low well to the southeast, and shear had decreased to a minimum. After reaching an initial peak intensity with 10-minute sustained winds of 205 km/h (125 mph) at 12:00 UTC that day, Fantala's intensity leveled off for the following 48 hours, with its 10-minute sustained winds fluctuating between 195 and 215 km/h (120 and 130 mph).

On 16 April, Fantala turned more to the west-northward toward the southern islands of the Seychelles, steered by a strengthening ridge near Madagascar. Intensification resumed by 12:00 UTC on the following day, with the JTWC estimating 1-minute sustained winds of 270 km/h (165 mph), classifying Fantala as a Category 5-equivalent tropical cyclone on the Saffir-Simpson scale. Around 15:00 UTC, the cyclone moved through the Farquhar Group of the Seychelles, and its eyewall moved over several small islands. At 18:00 UTC on 17 April, the MFR upgraded Fantala to a very intense tropical cyclone; based on a Dvorak T-number of T7.5, the satellite-derived wind estimate was 10-minute sustained winds of 250 km/h (155 mph), along with an estimated barometric pressure of 910 mbar (910.0 hPa; 26.87 inHg). However, in the best track for Fantala, the MFR concluded that Fantala had been a very intense tropical cyclone 6 hours earlier as well, with 10-minute sustained winds of 220 km/h (140 mph), and that the storm's peak intensity and minimum central pressure of 910 mbar (910 hPa; 27 inHg) had occurred 18 hours after that time, at 06:00 UTC on 18 April. The JTWC also estimated peak 1-minute sustained winds of 285 km/h (180 mph).

While maintaining peak intensity, Fantala's forward movement slowed as the ridge to its south over Madagascar weakened. The cyclone turned back to the southeast due to the building influence of a ridge to the northeast, and the storm retraced its former path. Cooler waters along its path – the result of upwelling – as well as another eyewall replacement cycle, caused Fantala to weaken to an intense tropical cyclone by 19 April. Fantala had maintained at least Category 4-equivalent intensity for about 90 hours, and of those 90 hours, Fantala spent about 30 hours at both very intense tropical cyclone status and Category 5-equivalent intensity. That day, the eye disappeared on satellite imagery and the storm deteriorated further to tropical cyclone status. The eye redeveloped on 20 April, with pronounced outflow assisting in the re-intensification, although increased shear resulted in weakening again on 21 April. That day, the MFR downgraded Fantala to a severe tropical storm. The structure improved again on 22 April as the system stalled due to the building ridge to the south. At 00:00 UTC that day, the MFR upgraded Fantala to an intense tropical cyclone once the eye became more pronounced again, only to downgrade it to tropical cyclone status by 06:00 UTC, though this was pushed back to 12:00 UTC in the best track. A small area of convection persisted over the center, although dry air in the region continued to weaken the thunderstorms.

The MFR again downgraded Fantala to a severe tropical storm on 23 April, as the storm began drifting to the northwest. Increasing wind shear weakened Fantala further to a moderate tropical storm that day, and on 24 April, both the JTWC and MFR issued their final advisories; the latter agency had first downgraded it to a tropical depression. By that time, the circulation was exposed from the convection as Fantala moved over cooled waters where it traversed a few days prior. The circulation continued to the northwest, with occasional flares of convection. By 27 April, a circulation was no longer present as the convective remnants of Fantala approached the coastline of Tanzania.