October Storms

About October Storms:

• The months of October-November and May-June see storms of severe intensity develop in the North Indian Ocean — comprising the Bay of Bengal and the Arabian Sea — with an average of five developing in a calendar year.
• In the past 131 years, October saw 61 storms develop in the Bay of Bengal, according to the Regional Specialised Meteorological Centre (RSMC).
• The east coast, notably Odisha, has faced many of its severest storms in October, including the Super Cyclone of 1999.

Formation:

• After the withdrawal of the Southwest monsoon, there is a rise in ocean heating, which leads to rise in sea surface temperature over the Bay of Bengal.
• The atmospheric moisture availability over the ocean region, too, is higher.
• So, when remnant systems from the South China Sea reach the Bay of Bengal, they get conducive conditions, aiding the formation and intensification of cyclones in October.
• In some years, ocean-atmospheric factors hinder this phenomenon.
• For instance, in 2020, weak La Nina conditions along the equatorial Pacific Ocean prevented a cyclonic formation near India’s coasts.

Cyclones in the Arabian Sea:

• In comparison with the Bay of Bengal, only 32 storms have developed in the Arabian Sea in October since 1891.
• Climatologically too, the IMD states that of the five storms formed in the North Indian Ocean in a calendar year, four are in the Bay of Bengal and one in Arabian Sea.

 

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Source : Indian Express