Tropical cyclone Alia in Bengal
Tropical cyclone moved across the Bay of Bengal it formed in the North Indian Ocean basin which comprises of Bay of Bengal and the Arabian Sea.For a tropical cyclone to form, sea surface temperatures must go beyond 27degree Centigrade, and this is prevalent throughout the year in some regions of the Bay of Bengal. Tropical cyclone storms most often develop near the Andaman Islands in the south-central Bay and then often moves northwest before curving Eastwards.The North of Indian Ocean is the only ocean basin in the world where there are two distinct tropical cyclone seasons in a year .The first tropical cyclone season peaks in April and May(Baisak month according to Hindu calender )popularly know as Kal Bashakhi, and the second in late October-early November. During the monsoon months, the large low pressure trough, within which tropical cyclone storms may form when over the ocean, moves inland bringing heavy showers of rain ,Tropical Cyclones are rare in the Bay of Bengal from January to March.Tropical cyclone storms forming in the pre and post periods of monsoon , are usually more violent and firece than the tropical cyclone in monsoon .The life span of these voilent tropical cyclone storms is approximately 4 days from the time it forms at sea until it moves over the land where it quickly spreads.
Tropical cyclone Storms are the more dangerous and harmful in Bangladesh,they kills many people and livestock and destroy houses and crops as they push inland with force. The effects of the storm surge are greatest when the storm hits at the time of high tide
Kolkatans were Taken by shock when tropical cyclone hit their land :-
As the kolkatans prayed for rain to ease the heat,a silent tropical cyclone brew 750 kms from kolkata deep inside the Bay of Bengal .A small patch of white cloud was seen over the sea by the radar of metrological office at 11.30 am on May 23 it looked threatening .A low pressure might have developed ,but it was thought that as usual it would change its way and pass away to Bangladesh The small cloud swelled into a mighty cyclone and headed to Kolkata. The Alia (tropical cyclone)wreaked havoc in the city ,its suburbs and across south Bengal leaving many dead. It
Flooded villages and forced thousands to vacant their homes .Building, trees and vehicals got hit by the wind of the tropical cyclone .The big trees fell on the road sides causing life caualty when trees collapsed due to the severe storm with a wind speed of 80 km /hour which hit Kolkata and its neighbouring districts with this Cyclone.
Thousands of people from two coastal southern districts were warned. People living in state capital Kolkata were requested to stay indoors, as tropical cyclone Aila advanced towards the region, packing winds up to 100 kms/hr (60 ms/hr).the speed of the stom was unpridictable sometimes high and sometimes low .
Apart from kolkata this tropical cyclone "Aila" had left more than 24,000 people homeless in the Sunderbans . The most affected islands are Dayapur, Jamespur,Annpore and Lahiripur lying close to the Sajnekhali forest in the Sunder bansof Bengal which lies near the delta area .the houses were diped 6ft deep into the water The high tide had left most of the villages distroyed

THE STORMY TRAILS (a sum up of the dreadening storm)May 23 11.30 am 'AILA" THE TROPICAL CYCLONE TOOK BIRTH OVER BAY OF BENGAL SOME 750 KMS AWAY FROM kolkata.May 25th 12.30 pm Northern tip os Aila reached kolkata .the storm ranged for 1 1/2 hours wind speed reached 120 kms/hr ..At 3.00pm the tropical cyclone reaches Kolkata lasting for another 45 mins speed reduced to 50 - 60 kms/hr .At 3..45 pm a second spell of cyclone started as southern tip reached the city .wind speed again shooting up to 120kms/hr .
Aila is the first storm to hit kolkata in 28 years.It was a severe tropical cyclone storm of catogory -II,it battered the city for six hours .Maximum speed touched 120 km/hr.It brought air train and land trafic to halt even ferries were closed which carry thousands of people across the river Ganga .all shops schools and collages and offices were shut down by 2 pm and finally at 5.30 pm it headed towards north taking toll over Sunder bans and Bangladesh .
An instrument called DOPPLER WEATHER RADAR it predicted before tropical cyclone "Aila" was born, warnings were issued but alarm bells were not rung .It was on Kolkata before the city knew what to expect .At 12.30 the wind speed picked and engulfed the city in its wrap