2011 North Indian Ocean cyclone season

2011 North Indian Ocean cyclone season
Season summary map
Seasonal boundaries
First system formedFebruary 2, 2011
Last system dissipatedDecember 31, 2011
Strongest storm
NameThane
 • Maximum winds140 km/h (85 mph)
(3-minute sustained)
 • Lowest pressure969 hPa (mbar)
Seasonal statistics
Depressions10
Deep depressions6
Cyclonic storms2
Severe cyclonic storms1
Very severe cyclonic storms1
Total fatalities367 total
Total damage$603 million (2011 USD)
Related articles
North Indian Ocean tropical cyclone seasons
2009, 2010, 2011, 2012, 2013

The 2011 North Indian Ocean cyclone season was the least active tropical cyclone season in the North Indian Ocean since 1993.[1] Only two cyclonic storms formed, below the average of four to six. 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.

This season was the first season since 1993 where only two named storms formed. However, the systems that formed would cause damages of greater than $1.64 million USD and cause approximately 360 fatalities. It is believed that La Niña, a quasiperiodic climate pattern which causes a rise in surface pressure over the Indian Ocean, making the region drier, was the main cause for the below-active activity in the basin.[2]

  1. ^ "Yearly and Seasonal Frequency of Cyclones and Depressions". India Meteorological Department. Retrieved September 5, 2012.(Note: Creation of an account in the website is required in order to access data.)
  2. ^ Colin Packham. "Australia says signs El Niño weather pattern forming". Reuters. Retrieved September 8, 2012.