Earth’s first category 5 tropical storm of 2021 is Tropical Cyclone Faraji in the southwest Indian Ocean.
Faraji took advantage of low wind shear of 5-10 knots and warm ocean temperatures of 28-29 degrees Celsius (82-84°F) to peak at category 5 strength with 160 mph winds and a central pressure of 920 mb at 1 pm EST Monday, February 8, according to the Joint Typhoon Warning Center (JTWC). Faraji’s intensity was estimated via the standard Dvorak technique, which uses infrared satellite imagery. In addition, 3-km resolution wind data from the synthetic aperture radar (SAR) instrument on Canada’s Radarsat-2 satellite revealed average winds of 157 mph in the southwestern quadrant of Faraji’s eyewall.
Fortunately, Faraji is over 500 miles from any land areas, and will pose hazards to marine interests and not to people this week. The storm is expected to gradually weaken as it moves eastward and then recurves to the south and west later this week, falling below hurricane strength by Saturday. By late next week, it is possible that Fariji will pose a threat to Madagascar and the nearby islands.
South Indian Ocean tropical cyclone history
NOAA’s hurricane history database lists 17 other tropical cyclones in the South Indian Ocean that have achieved category 5 strength since 1989; accurate satellite data in the region extends only back to about 1990. The strongest of these storms, Tropical Cyclone Fantala in 2016, peaked with maximum sustained winds of 180 mph and a central pressure of 907 mb pressure. Fantala did not make landfall, though its eyewall did affect the Farquhar Atoll while the storm was at category 5 strength.
No South Indian Ocean tropical cyclone has ever been recorded to make landfall at category 5 strength. At least 17 have made landfall at category 4 strength: two in mainland Africa, seven in Madagascar, and eight in western Australia.
Earth averaged 5.3 category 5 storms per year between 1990 and 2020, according to ratings made by NOAA’s National Hurricane Center and the U.S. Navy’s Joint Typhoon Warning Center. The quality of the Cat 5 database is too poor and the time series of decent data on these storms too short to make definitive conclusions about how climate change may be affecting these most fearsome of storms. However, climate change is expected to make category 5 storms stronger and more numerous in the coming decades.