Did monsoon have 'a new pattern this year'? Here's what weather experts say

"Monsoon reached different parts of the country rapidly due to a low-pressure area occurring in the Bay of Bengal (on Sunday)," the report quoted IMD scientist Naresh Kumar as saying.

Kumar added that the monsoon is usually activated by a low-pressure zone. "High-speed winds caused by the low-pressure zone led to monsoon rapidly reaching various parts of the country," he said. This led to rainfall in Maharashtra. "At the same time, the low-pressure zone pushed winds towards north-western India, including to Delhi, covering both regions at the same time," Kumar said.

He further explained that western winds from the Arabian Sea that push the monsoon further up coincided with the formation of the low-pressure zone in the Bay of Bengal when it was over Maharashtra.

According to weather experts, Cyclone Biparjoy had first delayed the monsoon in certain parts of the country and now, heavy to extremely heavy rainfall has lashed parts of India, causing crops damages and hampering transportation of agricultural produce in some areas.

DS Pai, a senior scientist at the IMD, had earlier explained how Cyclone Biparjoy had impacted the monsoon's progress over southern India and the adjoining western and central parts of the country.

He said, "Since the (cyclone) system absorbed most of the moisture, the monsoon's progress along the west coast was slow." However, the Bay of Bengal branch of the monsoon, responsible for bringing rains to the northeast and east India, remained stronger between June 11 and June 23.

Pai attributed this to a low-pressure system that formed over the Bay of Bengal in mid-June and the remnants of Cyclone Biparjoy, which aided the monsoon's advancement over east India.

The IMD previously stated that India is expected to receive normal rainfall during the southwest monsoon season despite the evolving El Nino conditions.

Northwest India is predicted to experience normal to below-normal rainfall, while the east, northeast, central, and south peninsula regions are expected to receive normal rainfall at 94-106 percent of the long-period average.

"This is annual variability. Every year the pattern is different," the expert said while dismissing speculations that the particular pattern was caused due to climate change.

Mahesh Palawat, VP-Meteorology & Climate Change, Skymet Weather Services, told CNBCTV18 that central parts of the country, particularly Vidarbha, Marathwada and parts of Madhya Pradesh and east Rajasthan, are likely to witness "decent rainfall".

"Western parts of Uttar Pradesh, parts of Punjab, Haryana, Delhi, Uttarakhand and Himachal Pradesh will witness moderate to heavy showers. Moreover, the rain activities will be heavy over Konkan and Goa, including Mumbai and suburbs for another 48 hours," he said.

Thereafter, rain activity will continue but with lesser intensity, he said. "So, we can say that the entire country is going to receive decent rainfall for at least the first week of July. So, the deficiency will be around 15 percent by the end of June," he added.

Palawat said the first 10 days seem to be promising for rainfall across the country and expects monsoon to progress further over western parts of Rajasthan as well.

He said the El Nino impact will be seen in the later part of July and there may be some deficiency in rainfall over many parts of the country. However, it will not be a drought-like condition.

"Therefore, we maintain our forecast of below normal rain that is 94 percent (long period average from June to September) because El Nino impact will be there, and Madden-Julian Oscillation (MGO) will also enhance rainfall in the month of July," he added.

The Southwest monsoon has already made a substantial progress, covering around 80 percent of India, according to KS Hosalikar, the Deputy Director General of Meteorology at the IMD.