eastern region oil spill disaster contingency plan - Indian Coast Guard

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surface currents have a tendency of flowing towards NE-Ely direction with
speeds of the order of 0.25 and 0.5 kts.
June and July
40. General. July is the cloudiest month of the year with sky cloudy to
overcast over most parts of the country and adjoining sea areas. The Southwest
monsoon normally establishes over the entire by the first week of this month.
The SWly winds with mean speed of 15-20 Kts are persistent over Bay of Bengal
and Andaman Sea.
41. Monsoon Trough. A trough of low pressure originating nom the
Northwestern parts of the country extends Southeast wards up to Head Bay. This
trough is known as 'Monsoon Trough' Monsoon Trough normally passes through
Ganganagar, New Delhi, Allahabad and Calcutta. Whenever Monsoon Trough
shifts to north or south of its normal position the strength of the monsoon varies.
Whenever the trough shifts southwards from normal position monsoon over
India strengthens and whenever weekends and Break Monsoon conditions are
experienced over the country.
42. Monsoon Lows /Depressions. Monsoon Lows/depressions form in
the North Bay near the end of the monsoon trough and travel normally along the
monsoon trough. Active monsoon conditions are associated with these monsoon
lows/ depressions. July is the most favorable month for the formation monsoon
depressions over Bay, North of 18 deg North. The frequency of formation of
Cyclone Storms and Depressions per year is 0.08 and .66 respectively.
43. Break Monsoon. When the Monsoon trough shifts towards the foothills of
Himalaya rainfall over most parts of the country decreases significantly and
rainfall increases along the foothills of Himalayas.
(a) Frequency of Break Monsoon. On an average there is one
break in the month of July.
(b) Duration. The duration of the break may vary 3 to 13 days. The
breaks, which occur in July, are short lived and generally last for 3 to 4
days. They are most frequent in the beginning of July and end of August.
(c) Synoptic Features. The synoptic features associated with the
Break Monsoon are given below:
(i) Northward shift of the Monsoon trough towards the foothills
of the Himalayas.