The eastern arm of the monsoon from the Bay of Bengal is terribly behind schedule. After making an early onset over complete northeast India on the 30th of May, almost a week ahead of schedule, the stream is finding it tough to move further. Monsoon line has been languishing over Sikkim, Sub Himalayan West Bengal and extreme northeast Bihar. Monsoon stream crosses Uttar Pradesh, Uttrakhand, and Himachal Pradesh and reaches the outskirts of Delhi, Punjab and Haryana around this time. Conditions are becoming favourable for the speedy advance of monsoon over the next 3-4 days.
Capital city Kolkata normally receives the first monsoon rains around 10th/11th June, coinciding with its arrival in Mumbai. It has been unduly delayed this season, by over two weeks. Even, the pre-monsoon showers deserted the capital city this month. The regional observatory at Alipore has recorded a mere 32mm of rainfall in June so far, against the monthly normal of 289mm. Such a huge shortfall at this stage will find it difficult to catch up at a later date.
Conditions are becoming favourable for monsoon to reach Kolkata, shortly. The monsoon stream has entered Gangetic West Bengal but remains on the outskirts of Kolkata, Howrah, Hooghly, Midnapore and South 24 Pargana. The northern limit has covered Barasat, Goberdanga and Krishnanagar, the extreme eastern edge of the state. The state has a shortfall of nearly 75% and Kolkata has over 80% rainfall between the 01st and 25th of June.
A cyclonic circulation has formed over the northwest and west Bay of Bengal, off the Odisha coast. It is likely to become more marked and a broad circulation will cover parts of West Bengal, Odisha, Bihar, Jharkhand and northwest Bay of Bengal, tomorrow. This pattern will support the trough all along the Indo-Gangetic plains, which will ultimately become the seasonal monsoon trough, a little later. Under the influence of this circulation and trough, monsoon showers are likely for Kolkata on 29th June. Pre-monsoon activity will continue prior to the onset of monsoon. Monsoon rains are expected to continue from the fag end of the month to the first week of July for the city and suburbs. Isolated heavy showers are also likely during this period.
