Severe Cyclonic Storm Amphan in Bay of Bengal :

According to the National Weather Forecasting Centre of the Indian Meteorological Department (IMD) under Ministry of Earth Science issued a very severe cyclonic storm warning (predicted on 15th May)  for the central parts of South Bay of Bengal and predict heavy rain and high speed wind in parts of India's East coast and Andman & Nicobar Islands.

Amphan is pronounced as 'Um-pun'. It's named by Thailand according naming rules. 

Amphan may affect the Tamil Nadu, Kerala, Andhra Pradesh, Odisha & West Bengal and dissipate after hitting Bangladesh (in India mainly Odisha & West Bengal worst affected by Amphan).

Classification of Tropical Cyclones : 

The criteria followed by Meteorological Department of India (MDI) to classify the low pressure system in the Bay of Bengal and in the Arabian Sea as adopted by World Meteorological Organisation are as under :
* Low Pressure area : wind speed less than 17 knots (<31kmph).
* Depression : wind speed from 17 to 27 knots (31 to 49 kmph).
* Deep Depression : wind speed from 28 to 33 knots (50 to 61 kmph).
* Cyclonic Storm : wind speed from 34 to 47 knots (62 to 88 kmph).
* Severe Cyclonic Storm : wind speed from 48 to 63 knots (89 to 118 kmph).
* Very Severe Cyclonic Storm : wind speed from 64 to 119 knots (119 to 221 kmph).
* Super Cyclonic Storm : wind speed above 119 knots (more than 221 kmph)

Very Severe Cyclonic Storm Amphan turn to 'Super Cyclonic Storm'.
Super Cyclonic Storm equivalent of a strong category 4/weak category of 5 on the Saffir Simpson Scale. It weakened ahead of landfall on Wednesday 20 May as a Very Severe Cyclonic Storm (Strong Category 2 equivalent), bringing dangerous winds storm surge and flooding to coastal areas of West Bengal in India and Bangladesh.

Why more Cyclones appear in Bay of Bengal than Arabian Sea :

Majority of the cyclone affecting India originate from the Bay of Bengal striking the eastern coast. The ratio of tropical cyclone occurred in between Bay of Bengal and Arabian sea is 4:1. (Bay of Bengal sea are more hoter than Arabian sea and also, the hills in the western Ghats are some extent to stop the cyclones strike the coast).

IMD Heavy Rainfall Warning Zones :

Odisha : 

Coast of Odisha experience moderate rainfall at various places with heavy fall at isolated places from 19th May evening (Bhadrak, Balasore & Maturbhanj).

West Bengal :

On 20 th May heavy rainfall over Gangatic West Bengal (east & west Medinipur, south & north 24 Paraganas, Howrah, Hoogli, Kolkata adjoining districts).

Wind Warning in West Bengal & Odisha :

High wind speed in Odisha on 19th May and in West Bengal on 20th May. (Wind speed approx 120 to 140 kmph).

Damage Expected in West Bengal and Odisha :

* Destruction of all types of kuchha houses, badly damage old pucca structure.

* Bending or uprooting power and communication poles.

* Disruption of rail /road link on several places.

* Damage agriculture

* Uprooting of trees.

* Boats, country crafts may get detached from mooring.

Government Actions :

* NCMC (National Crisis Management Committee) to review the preparedness of States and Central Ministry/Agencies to deal with the cyclonic storm Amphan.

* Government provided food grains, drinking water, and other essential supplies and services.

* The rescue and relief teams of Army and Navy along with ships and aircrafts of the Navy, Air force, and coast guard have been put on standby.

* Coordination between Central and State Governments.

* The National Disaster Response Force has sent 7 teams to West Bengal & 10 teams to Odisha to provide assistance the State Government in its relief measures.

* Complete suspension of fishing operations till Cyclonic dissipation.

* Judicious regulation of rail and road traffic.

* People in affected areas to remain indoor.

* It has advised fisherman not venture into sea from May 15.

People of West Bengal and Odisha fight against Amphan cyclone along with Covid-19 crisis.