This timeline documents all the events of this season, including the strengthening, weakening, formation, dissipation, and landfall of tropical cyclones in both the Bay of Bengal and the Arabian Sea. When depressions form in the Bay of Bengal, they receive the prefix BOB by the India Meteorological Department (IMD). Likewise, depressions which form in the Arabian Sea are designated the prefix ARB, and those which form over land are given the prefix LAND. The Joint Typhoon Warning Center (JTWC) also creates advisories on storms in the North Indian Ocean. It designates the prefix B for storms that form in the Bay of Bengal, and the prefix A for those which form in the Arabian Sea. Best track data from the IMD and JTWC is utilized in this article, which means that post-storm analyses take precedence over operational advisories and the like. Meteorologists use one time zone, Coordinated Universal Time (UTC), when issuing forecasts and advisories.[5] As such, the time of the events in this season are listed in UTC as well as the local time, which is, in this case, Indian Standard Time (IST).
07:00 UTC (12:30 p.m. IST) – The IMD reports that Depression BOB 03 has crossed the North Odisha and the West Bengal coast between Balasore and Digha.
August
1 August
03:00 UTC (8:30 a.m. IST) – The IMD reports that Depression BOB 03 has weakened into a well-marked low pressure area over southeast Madhya Pradesh and neighboring Chhattisgarh and Vidarbha.[9]
03:00 UTC (8:30 a.m. IST) – The IMD reports that Depression LAND 01 has become a well-marked low-pressure area over the central area of south Madhya Pradesh and Vidarbha.[10]
09:00 UTC (2:30 p.m. IST) – The IMD reports that Depression Phailin has weakened to a well-marked low pressure area over southwest Bihar and the areas surrounding it.[3]
07:30 UTC (1:00 p.m. IST) – The IMD reports that Depression BOB 05 has made landfall on the Tamil Nadu coast near Nagapattinam.[12]
17 November
00:00 UTC (5:30 a.m. IST) – The IMD reports that Depression BOB 05 has weakened to a well-marked low pressure area over northern Tamil Nadu and the areas surrounding it.[12]
00:00 UTC (5:30 a.m. IST) – The IMD reports that Depression Helen has degenerated to a well-marked low pressure area over coastal Andhra Pradesh and the areas surrounding it.[13]
18:00 UTC (11:30 p.m. IST) – The IMD reports that Depression Lehar has weakened to a well-marked low-pressure area over coastal Andhra Pradesh and adjoining Telangana.[14]
13:30 UTC (7:00 p.m. IST) – The IMD reports that Depression Madi has made landfall on the Tamil Nadu coast near Vedaranyam. It later crossed back into the Palk Strait.[15]
17:00 UTC (10:30 p.m. IST) – The IMD reports that Depression Madi has made landfall on the Tamil Nadu coast again near Tondi.[15]
13 December
00:00 UTC (5:30 a.m. IST) – The IMD reports that Depression Madi has weakened to a well-marked low pressure area over the southeast Arabian Sea near the Kerala coast.[15]
^ abA Preliminary Report on Land Depression(PDF) (Report). New Delhi, India: India Meteorological Department. August 2013. Archived(PDF) from the original on April 2, 2021. Retrieved March 27, 2021.