The 1999 North Indian Ocean cyclone season was an event in the annual cycle of tropical cyclone formation. The North Indian Ocean cyclone season has no official bounds, but cyclones tend to form between April and December, with peaks in May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northern Indian Ocean. 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. The tropical cyclone scale for this basin is detailed on the right. On average, 4 to 6 storms form in this basin every season. The season produced an average number of storms but there was an above average number of intense cyclones. In May, a Category 3 cyclone struck Pakistan, leaving at 700 people dead or missing. In October, two very intense cyclones struck eastern India within two weeks of each other with the latter becoming the most intense Northern Indian Ocean cyclone on record, leaving over 10,000 people dead and causing more than $4.5 billion (1999 USD) in damages. Season summary During the 1999 season, a total of ten tropical cyclones were observed. The India Meteorological Department, the official Regional Specialized Meteorological Center of the North Indian Ocean basin, identified eight of them. The Joint Typhoon Warning Center unofficially tracked two additional cyclones, 03B and 31W, during the course of the season. Systems Severe Cyclonic Storm BOB 01 On January 30, an area of disturbed weather began to develop. Convection began to form around the center and a Tropical Cyclone Formation Alert was issued the next day by the JTWC. Development of the storm stalled and the alert was cancelled. The next day, another TCFA was issued but was once more cancelled. Finally, on February 2, after the third TCFA was issued, the low pressure area developed into a tropical storm at 0900Z 370 nm west of Phuket, Thailand. The storm slowly intensified and