The IMD began tracking a depression located to the west of Sumatra on 26 April, classifying it as BOB 02. Later that day, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert on the system.^[5] Afterward, the storm slowly coalesced while moving northward, and was upgraded to a deep depression at 00:00 UTC on 27 April.^[6] At the same time, the JTWC began warning on the system, designating it 01B.^[7] Six hours later, the IMD upgraded the system to a cyclonic storm and gave it the name Fani.^[8]

The system continued to intensify until 18:00 UTC on 27 April, after which it stagnated for over a day, as convection around the storm's center waxed and waned.^[9] Fani resumed strengthening around 12:00 UTC, with the IMD upgrading it to a severe cyclonic storm.^[10] At that time, Fani began a period of rapid intensification as it was located within a very favorable environment with sea surface temperatures of 30–31 °C (86–88 °F) and low vertical wind shear. As a result, the JTWC upgraded Fani to a Category 1-equivalent cyclone late on 29 April.^[11] Around 00:00 UTC on 30 April, Fani was upgraded to a very severe cyclonic storm by the IMD.^[12] The organization of the system continued to improve, with tight spiral banding wrapping into a formative eye feature,^[13] resulting in Fani being upgraded to an extremely severe cyclonic storm by the IMD around 12:00 UTC^[14] while the JTWC upgraded the storm to a Category 3-equivalent cyclone hours later.^[15] Development proceeded more slowly over the following days, with little improvement evident in the system's satellite presentation. On 2 May, however, the central dense overcast became more symmetrical and the eye more distinct, and Fani was upgraded to a Category 4-equivalent cyclone by the JTWC at 06:00 UTC.^[16] Shortly after, Fani started another period of rapid intensification, attaining 1-minute sustained winds of 280 km/h (175 mph), equivalent to a Category 5 hurricane, according to the JTWC,^[17] tied with Cyclone Mocha as the strongest storm on record in the north Indian Ocean, in terms of 1-minute sustained winds. Operationally, the JTWC classified the system as a high-end Category 4-equivalent tropical cyclone with 1-minute sustained winds of 250 km/h (155 mph),^[18] but raised their estimate in post-season reanalysis.

Fani quickly weakened after peak intensity. At 8:00 a.m. IST (02:30 UTC) 3 May, Fani made landfall near Puri, Odisha as an extremely severe cyclonic storm, with 3-minute sustained winds of 185 km/h (115 mph) and 1-minute sustained winds of 230 km/h (145 mph) according to IBTrACS record.^[19] This made Fani the most intense storm to make landfall in India's Odisha state since the 1999 Odisha cyclone.^[20] Land interaction quickly degraded Fani's convective structure; and it weakened to a Category 1-equivalent tropical cyclone soon after landfall.^[21] Fani continued to weaken after landfall, weakening to a cyclonic storm later that day,^[22] before passing just north of Kolkata. On 4 May, Fani weakened to a deep depression and moved into Bangladesh,^[23] before degenerating into a well-marked low later on the same day.^[24] On 5 May, Fani's remnant low dissipated over Bhutan.^{[citation needed]}

Fani developed during a period of high concentration of anthropogenic aerosols in the Bay of Bengal with abnormally high sea surface temperature (SST), thereby presenting a compound effect of atmospheric aerosols and regional climate warming on a tropical cyclone. Research indicates that aerosol and its interaction with the atmosphere acted to mitigate the strengthening effect of anthropogenic warming on Fani, but was not strong enough to entirely counteract it.^[25]

The India Meteorological Department tracked the storm and issued numerous yellow warnings for much of the south-eastern portion of India when the cyclone started to intensify.^[26][27] In preparation for the storm's impact, the state government of Odisha and its agency OSDMA evacuated over 1.2 million residents from vulnerable coastal areas and moved them to higher ground and into cyclone shelters built a few kilometres inland. The authorities deployed around a thousand emergency workers and 43,000 volunteers in these efforts. It sent out 2.6 million text messages to warn of the storm in addition to using television, sirens and public-address systems to communicate the message. About 7,000 kitchens were operated to feed evacuees in 9,000 storm shelters.^[28][29]

The Indian Navy readied naval ships and aircraft at Arakkonam and Visakhapatnam air-bases to prepare for the storm's aftermath and aid in reconnaissance, rescue and relief operations.^[30] The Odisha government staged "300 power boats, two helicopters and many chain saws, to cut downed trees" for the purpose.^[29]

Authorities in Bangladesh were ordered to open shelter areas as well in 19 coastal districts.^[31] Bangladesh Navy deployed 32 naval ships to provide emergency relief and medical assistance to the coastal areas in case of any emergencies.^[32] More than 1.2 million people were evacuated in Bangladesh and moved to the cyclone shelters in coastal areas.^[33]

Odisha edit

Approximately 72 people have been killed by Fani in India; 64 in Odisha,^[34] In Odisha, a teenager of 14 years was killed after being hit by a falling tree. One woman died when she was hit by flying debris, and another died of a heart attack while in a cyclone shelter.^[35] The cyclone adversely affected electricity supply and telecommunication in several coastal areas of Odisha, and to a lesser extent, of West Bengal. Puri and Khordha district in Odisha were the worst hit.^[28] The Jagannath Temple in Puri suffered minor damage, the repairing cost were estimated to be ₹51 million (US$738,000).^[36] The KIIT University also suffered a damage of about ₹300 million (US$4.3 million).^[37] Total damage in Odisha were estimated at ₹120 billion (US$1.74 billion), mostly in property damage and the relief.^[38] After the cyclone, Odisha required ₹170 billion (US$2.46 billion) for rebuilding the infrastructure.^[39] Indian Prime Minister Narendra Modi announced that the government had released over ₹10 billion (US$145 million) for the states affected by Fani.^[40] There were massive environmental devastation, as well.^[41]

Andhra Pradesh edit

Although no fatalities occurred in Andhra Pradesh, Srikakulam and Vizianagaram districts reported an economic loss of ₹586.2 million (US$8.5 million).^[42] The South Central Railway also suffered a damage of about ₹29.8 million (US$432,000).^[43]

Bangladesh edit

Fani killed 17 people in ten districts of Bangladesh.^[44] In Bagerhat District, a woman died after being hit by a falling tree, and 7 of them were killed by lightning in two districts of Bangladesh.^[45][46] The cyclone also destroyed about 63,000 ha (160,000 acres) of farmland in 35 districts of the country, the agricultural loss were at ৳385 million (US$4.6 million).^[47] Total damage in Bangladesh were up to ৳5.37 billion (US$63.6 million).^[48]

The Bangladeshi government distributed rice, dried food, and ৳19.7 million (US$234,000) to those affected by the cyclone.^[49]

CHD Group supported the Government of Odisha through provision of medical relief with extended support from All India Institute of Medical Sciences, Bhubaneshwar. ^[50] Gurgaon-based NGO Meals of Happiness Charitable Trust, in association with M3M Foundation, ran a major relief drive for the victims of cyclone Fani which had devastated various districts of Odisha last month.^[51]

• 1999 Odisha cyclone – The strongest cyclone on record to strike Odisha; also the most intense storm recorded in the North Indian Ocean, which killed over 10,000 people
• Cyclone Viyaru – Took a similar path and affected Bangladesh and Myanmar in 2013
• Cyclone Phailin – A powerful tropical cyclone that struck Odisha in 2013, which displaced over 1 million people
• Cyclone Matmo–Bulbul
• Cyclone Amphan – A powerful Super Cyclonic Storm that affected similar areas in 2020
• Cyclone Mocha - Another cyclone that is tied with Fani as the strongest storm on record in the north Indian Ocean, in terms of 1-minute sustained winds.
• List of near-Equatorial tropical cyclones

• India Meteorological Department
• Archived version of 01B.FANI from the U.S. Naval Research Laboratory
• ReliefWeb's main page for this event.