eastern region oil spill disaster contingency plan - Indian Coast Guard

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the wind speed may reach to a value of 30-50 kts. Squalls accompanying
Norwesters over Gangetic West Bengal are severe the maximum speed of which
is of the order of70-75 kts.
28. Low Pressure System. In the month of April the formation of "Low
Pressure Areas/ Depressions over the Indian Seas commences. The number of
systems forming is comparatively more in the second half of the month. Bay of
Bengal is more prone to Cyclonic storms than the Arabian sea. A majority of
these Low Pressure Areas/ Depressions intensify into Cyclonic Storms. In the Bay
of Bengal Low Pressure Areas! Depressions form mainly south of Lat 15 deg
North and of Long 85 deg East. The frequency of formation of Cyclone Storms,
Severe Cyclonic Storms and Depression per year is 0.08 respectively. Majority of
these disturbances move initially in Northerly/ Northwesterly direction and
later recurve to strike Bangladesh / Arakkan Coast.
29. Currents off Orissa, Andhra and Tamil Nadu coast. Along
Andhra, Orissa Coasts surface water currents flow towards NEly direction with
average speed of the order of ½ - ¾ kts file along Tamil Nadu coast they are
generally towards NNEly / NEly with speeds reaching ¾ Kts.
May
30. General. May is the last month of the, ''Hot Weather Period" i.e Pre
Monsoon Season”.
31. Heat Low. The shallow heat low which establishes itself over NE
Madhya Pradesh adjoining Uttar Pradesh and Bihar m. the month of April shifts
to North-Western parts of the Indian Sub-Continent and establishes itself near 30
deg N and 75 Deg E by end of May.
32. Isobaric Pattern. In the beginning of May the isobars continue to
run parallel to the coast as in the month of April. However with the shift of the
heat low to the North - Western pats of the country, the isobaric configuration
undergoes significant changes towards end May. By this time, the isobars
become East -West oriented with pressures decreasing towards the North.
33. Pressure Gradient. The pressure gradient along the East and West
Coasts also becomes steep. Besides, m. the case of an early advance of the SW
Monsoon the weak high pressure cell (anticyclone) over the Arabian sea which is
normally prevalent through the month of May, suddenly collapses.
34. Surface Wind. S/SW winds predominate along and off the coastal
areas of Andhra Pradesh. The mean wind force during the month of May is 3 to 4