Southwest monsoon has jumped multiple timelines issued by the weather agencies for the national capital Delhi. It continues to elude and remain parked at the doorsteps with the monsoon line not budging from Aligarh and Meerut. It has been so near, yet so far seeming like a distant pedestal refusing even to crawl for the last one month (13th June). But now, Monsoon 2021 is likely to make a soft and mild start today, late in the evening or night with some patchy intermittent rain drizzle. The true spirit and feel of monsoon to sink in, for a common man will still be a mirage and will have to wait till the weekend.
There are visible changes in the atmosphere with reversal of winds to easterlies, rise in the humidity, and persistent low clouds in the morning with a gentle breeze. But these changes are falling short to manifest as rains, the most important of all, and therefore slippage of timelines. These conditions will just suffice to bring light rain and drizzle today towards the later part of the day to marginally fulfill the criterion of monsoon. It may not be spread out to cover all parts of the capital and suburbs.
Meteorologically, there are 2 significant systems controlling weather activity over most parts of the country. A low-pressure area over northwest Bay of Bengal, off Andhra Pradesh and Odisha coast, and a cyclonic circulation over Northeast Arabian Sea and adjoining Gujarat coast. A shear line is connecting these 2 features and controlling the weather activity from Andhra Pradesh to Gujarat, across Chhattisgarh, Telangana, and Maharashtra. Monsoon trough has shifted far to the south, increasing span of easterly winds across Bihar, Jharkhand, Madhya Pradesh, Uttar Pradesh, Delhi, Rajasthan, and Haryana. Such conditions are not conducive for intense and widespread rains over North India including Delhi. However patchy intermittent rain and drizzle remain a possibility for some areas. Suitable timings for this activity being late evening and night as the temperatures drop and therefore easier for the moist air to shed the water content.
From the expectation of early arrival of monsoon on 15th June to possibly the most delayed one since 2002, is very much on the cards. In 2002, the monsoon arrived on 19th July and the most delayed in recent history was 1987, when it breached the mark on 26th July. Both these years, 1987 and 2002, were severe droughts for the country with a rainfall deficiency of about 20%. Hopefully, this year's coincidence with the past will be of late arrival only, and seasonal rains not likely to get impacted. An extensive wet spell for many parts of the country is waiting in wings between 13th and 20th July, particularly for Gujarat, Rajasthan, Madhya Pradesh, Maharashtra, Delhi, Haryana, Punjab, Uttar Pradesh, Bihar, Jharkhand, Andhra Pradesh, Telangana, Kerala and West Coast including Mumbai.