During 2021, tropical cyclones formed in seven major bodies of water, commonly known as tropical cyclone basins. Tropical cyclones will be assigned names by various weather agencies if they attain maximum sustained winds of 35 knots. During the year, one hundred forty-five systems have formed and ninety-one were named, including one subtropical depression and excluding one system, which was unofficial. One storm was given two names by the same RSMC. The most intense storm of the year was Typhoon Surigae, with maximum 10-minute sustained wind speeds of 220 km/h (140 mph) and a minimum pressure of 895 hPa (26.43 inHg). The deadliest tropical cyclone was Typhoon Rai, which caused 410 fatalities in the Philippines and 1 in Vietnam, while the costliest was Hurricane Ida, which caused an estimated $75.25 billion USD in damage after striking Louisiana and the Northeastern United States.

Cyclonic Storm Gulab and Severe Cyclonic Storm Shaheen were two tropical cyclones that caused considerable damage to South and West Asia during the 2021 North Indian Ocean cyclone season. Gulab impacted India and Pakistan, while Shaheen impacted Iran, Oman and the United Arab Emirates. Gulab was the third named storm of the 2021 North Indian Ocean cyclone season, as well as the fourth named storm of the season after its reformation in the Arabian Sea as Shaheen. The cyclone's origins can be traced back to a low-pressure area situated over the Bay of Bengal on September 24. The Pakistan Meteorological Department named this new cyclone Gulab.On September 26, Gulab made landfall in India's Andhra Pradesh but weakened overland, before degenerating into a remnant low on September 28. The system continued moving westward, emerging into the Arabian Sea on September 29, before regenerating into a depression early on September 30. Early on October 1, the system restrengthened into a Cyclonic Storm, which the IMD named Shaheen. The system gradually strengthened as it entered the Gulf of Oman. While slowly moving westward, the storm turned southwestward, subsequently making an extremely rare landfall in Oman on October 3, as a Category 1-equivalent cyclone. Shaheen then rapidly weakened, before dissipating the next day.