eastern region oil spill disaster contingency plan - Indian Coast Guard

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and gradually increases till the hot weather period is terminated by the on set of
South West Monsoon. A brief description of significant weather expected over
the areas of interest is given below:-
(a) Andhra Pradesh and East Tamil Nadu. Thunderstorm activity
over coastal Andhra and east Tamil Nadu is less. On an average the
number of days of thunder activity over Visakhapatnam during march is
one and the frequency increases to 04 and 07 during the months of April
and May respectively.
(b) Gangetic West Bengal Bihar & Orissa. These regions
experience high frequency of thunderstorms, which are accompanied by
moderate to severe squalls approaching from northwesterly direction. They
are known as Northwesters and are associated with high wind speeds of
the order of 140-150 Km/h and result in considerable damage to property
and lo0ss of life., These systems are also known as ‘Kal – Baisakhies’.
(c) Occurrence. The Norwesters activity is very less during March
starts mainly during the moth of April and reaches its peak towards the
end of hot weather period. Movement the Norwesters normally develop
Bihar plateau, adjoining southeast Madhya Pradesh and west Orissa in the
afternoon hours and move towards Gangetic west Bengal and Head of Bay
of Bengal. They advance upto 80 to 100 miles into the sea.
15. Sub –Tropical Jet Stream. The sub tropical jet streams (35,000 to
40000). Though winter phenomenon, continues to be another prominent
synoptic feature occurring over North, North East India during the month of
March. The occurrence of weather in the form of thunder activity as a result of
the super imposition of the jet stream over a western disturbance or an induced
low moving across Northern and central parts of India is a normal phenomenon
during the month of March. In addition on large Gangetic West Bengal, Bihar and
Orissa and thunder activity over Assam and adjoining states are also closely
related to the presence of jet stream over these areas.
16. Cold Wave. The occurrence of cold waves in the Central parts of the
country during the month of March reduces appreciably. The peninsular India
virtually becomes free from cold wave activity.
17. Cyclonic Storms / Depressions. They form between 5 Deg to 8Deg
North and East of 85 Deg East in the South Bay of Bengal. The frequency of
formation of Cyclone and Depression per year is 0.38 and 0.48 respectively.