2023 North Indian Ocean cyclone season

The 2023 North Indian Ocean cyclone season was an above-average and deadly season, becoming the most active since 2019, with nine depressions and six cyclonic storms forming. It was the deadliest since 2017, mostly due to Cyclone Mocha, and had the second-highest accumulated cyclone energy (ACE) in the basin, after the 2019 cyclone season, which was itself the second most active North Indian Ocean cyclone season on record in terms of cyclonic storms. The 2023 season also had the most extremely severe cyclonic storms on record, tying with 1999 and 2019. The North Indian Ocean cyclone season has no official bounds, but cyclones tend to form between April and December, with the peak from May to November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northern Indian Ocean. However, a cyclone can form at any time during the year shown by an unnamed depression that affected Sri Lanka in January–February.

The scope of this article is limited to the Indian Ocean in the Northern Hemisphere, east of the Horn of Africa and west of the Malay Peninsula. There are two main seas in the North Indian Ocean — the Arabian Sea to the west of the Indian subcontinent, abbreviated ARB by the India Meteorological Department (IMD); and the Bay of Bengal to the east, abbreviated BOB by the IMD.

The official Regional Specialized Meteorological Centre in this basin is the India Meteorological Department (IMD), while the Joint Typhoon Warning Center releases unofficial advisories for interest. On average, three to four cyclonic storms form in this basin every season.