While the southwest monsoon is preparing to resume its journey over the Andaman Sea and the Bay of Bengal, meteorological conditions over the Arabian Sea seem to be heating up for triggering cyclogenesis. These are rather early pointers of a likely disturbance churning over the warm waters of the Arabian Sea. Initial indications do suggest the possibility of a tropical storm coming up in the early part of 2nd week of June 2023. It is rather premature to comment on anything more than this at this stage.
June being the monsoon onset month is not very familiar for hosting tropical storms over Indian Seas. Monsoon stream starts appearing close to the equator during the last week of May or sometimes even early. Strengthening of cross-equatorial flow becomes the precursor for the likely advance of monsoon winds. Disruption of seasonal patterns over central and southern parts of the Arabian Sea restricts the build-up of cross-over of trade winds. This, in turn, delays the monsoon current and its scheduled arrival over the mainland.
The absence of any strong current over the equatorial Arabian Sea favours the popping up of small-scale perturbations which later grow at the expanse of suitable environmental conditions. During the summer monsoon, the Bay of Bengal is always warmer than the Arabian Sea. However, during unsettled conditions, the Arabian Sea limits the transfer of heat to the deeper layers. Such a situation becomes conducive for the formation of tropical storms before the advent of southwest monsoon.
The formation of a circulation over the South Central Arabian Sea will precede the appearance of a low-pressure area next week. Cyclonic circulation may appear as early as 02nd/03rd June and reorganize to become low-pressure area on 05th June. Further consolidation will take place for the subsequent 72hr, without any significant drift of the weather system. Environmental conditions are quite favourable and therefore probability of 1st tropical storm of the year over the Arabian Sea stands a fair chance. Notwithstanding, these developments will be subjected to very close observation and monitoring.
Tropical storms forming over the Arabian Sea usually track away from the West Coast. Mostly, these weather systems head for Somalia, Yemen and Oman. Few of them do threaten the state of Gujarat and the Konkan region. Irrespective of the final track, such systems move northwestward away from the Indian coastline, at least till the central parts of the Arabian Sea. Such a track will also coincide with the arrival time of the monsoon. Arabian Sea storms drifting away from the coastline does not augur well for the progress of monsoon deep inland of Peninsular India. Suffice to say, wait and see with fingers crossed.