Later that day, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert on the system.

[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.

[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.

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.

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.

[20] Land interaction quickly degraded Fani's convective structure; and it weakened to a Category 1-equivalent tropical cyclone soon after landfall.

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.

[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.

[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.

[35] The cyclone adversely affected electricity supply and telecommunication in several coastal areas of Odisha, and to a lesser extent, of West Bengal.

[39] Indian Prime Minister Narendra Modi announced that the government had released over ₹10 billion (US$145 million) for the states affected by Fani.

[49] 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.