No. IV-18.4 - (IMD), Pune

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the incidence of storms in this month. Most of the storms that strike the
coast south of 15°N enter the Arabian Sea and reintensify. In the Arabian
Sea, the direction of movement of storms is generally westerly. However,
east of 70°E some of the storms move northnorthwestwards and later recurve
northeast to strike the north Maharashtra-Gujarat coasts.
ii) November: The source region of the majority of storms in this month is
between 8°N and 13°N. Those which move in a westnorthwesterly direction,
strike Tamil Nadu coast and emerge into the Arabian Sea where they re—
intensify. Bay storms which form in more northerly latitudes move northwest
and later recurve towards the northeast. In the Arabian Sea, the
initial movement is northwesterly. Storms which go north of 15°N recurve
towards the northeast and strike the north Maharashtra-Gujarat coasts.
iii) December: There is an appreciable decrease in the frequency of storms
from November to December. Most of the storms originate over the Bay of
Bengal between 5°N and 10°N. Those which originate over the southwest Bay
move initially in a northwesterly direction and strike the south Tamil Nadu
coast or the northeast coast of Sri Lanka. A few of these enter the Arabian
Sea. However, they do not intensify but dissipate. Storms which originate
in the southeast Bay generally move in a northnorthwesterly direction
and later recurve towards northeast. During their northeasterly
course they show a tendency to weaken and dissipate. Storms in the Arabian
Sea are very few in December and almost all of them are of Bay origin.
12.1.3 Table V gives the monthly frequency of cyclonic storms and depressions
in the Bay of Bengal and Arabian Sea.