The 2017 North Indian cyclone season includes events in the annual cycle of tropical cyclone formation . The cyclone season in the North Indian has no official limits as is usual in other basins, but runs all year round. The tropical cyclones usually form in this basin between April and December, with the months before and after the monsoon season , i.e. April / May and October / November, being the most active. A tropical cyclone in the Indian Ocean is known as a cyclone .
The Regional Specialized Meteorological Center (RSMC) responsible for the Indian Ocean between the Horn of Africa and the Malay Peninsula is the India Meteorological Department in New Delhi . This gives a name to those tropical cyclones that have at least the status of a cyclone. Low pressure areas (depending on the wind speed depressions or deep depressions ) are numbered consecutively, with the letter combination BOB indicating that the system was formed in the Bay of Bengal . The letters ARB stand for the Arabian Sea . Typically three to four cyclonic storms per year form in the Indian Ocean north of the equator.
The Joint Typhoon Warning Center (JTWC) in Honolulu issues separate warnings and forecasts for the US facilities in the Indian Ocean. The JTWC classifies according to the Saffir-Simpson hurricane wind scale , while the RSMC uses its own criteria for the classification, which are based, among other things, on the measurement of the continuous wind speed on the basis of a three-minute observation.
The first storm of the season was Maarutha in the Bay of Bengal; the storm developed in mid-April. The strongest storm of the season was Ockhi, which grazed the coast of southern India at the end of November with three-minute winds of 140 km / h.
On April 13, under the influence of an existing area with strong convection, a low pressure area formed within six hours in the southern Bay of Bengal. Under favorable conditions, the system quickly deepened, and on April 15 the system was classified as ams depression. During the day it intensified first into a deep depression, then into the Cyclonic Storm Maarutha. Maarutha triggered heavy rainfall in Sri Lanka as well as the Andaman and Nicobar Islands as a depression. On April 16, Maarutha moved overland in Myanmar and the next day dissolved into a pronounced low pressure area.
Maarutha destroyed more than 70 households in Kyaukpyu and property damage was estimated at 31.8 million kyat ( US $ 23,400) on April 18 . In Myanmar, three people were killed as a result of the storm.
Under the influence of already existing convection, a low pressure area formed on May 26th in south-eastern Goolf of Bengal. It got worse quickly, and on May 28th the RSMC classified the system as Depression and then Deep Depression. In the morning hours of May 29, the RSMC reported that the system had reached storm force and gave it the name Mora . The storm moved parallel to the coast of Myanmar in a north-northeast direction and shortly before crossing the coast of Bangladesh reached its peak intensity as Severe Cyclonic Storm with 3-minute wind speeds of 110 km / h and a minimum central air pressure of 978 hPa (mbar). According to the JTWC, the storm with one-minute wind speeds of 120 km / h is just category 1 on the Saffir-Simpson hurricane wind scale . Shortly afterwards, at 6:00 a.m. IST , Mora crossed the coast of Bangladesh near Chittagong. Due to the effects of the land, the storm quickly weakened and on May 31, it dissolved over Meghalaya into a clearly recognizable low pressure area.
As of May 31, the day the eye struck in Bangladesh, nine people were killed by the effects of Mora.
Before the system became tropical, it amplified the arrival of monsoon rains and caused severe flooding in Sri Lanka and the Andaman Islands , part of India , in which well over 200 people died.
Tropical storm Ockhi formed at the end of November on the southern tip of India and subsequently developed into a cyclone. In India, Ockhi killed 39 people, in Sri Lanka the cyclone claimed 14 lives. Millions were without electricity. The Indian Navy used warships, helicopters and airplanes to search for around 180 missing fishermen. In the first days of December the storm moved across the Arabian Sea . The central seawater desalination plant was damaged on Kavaratti in the Lakkadiven archipelago .
Tropical cyclones in the Indian Ocean are named by the RSMC of the India Meteorological Department . The names are used only once each, so no devastating storm names are removed from the list of tropical cyclone names after the season ends . Storms that pull over from the western Pacific Ocean and maintain their circulation will continue to be listed under the name given there. The RSMC assigns a name if a system is classified at least as a Cyclonic Storm . The next six names are:
Maarutha
Mora
Ockhi
Sagar (unused)
Mekunu (unused)
Daye (unused)
Seasonal effects
The following table lists all tropical storm systems that developed in the northern Indian Ocean in 2017, their names, their peak intensity (according to the IMD storm scale) and the sum of property damage and personal injury. The stated damage amounts include damage caused by a storm before and after its tropical existence and are given in US dollars at 2017 prices.
