New Delhi: The India Meteorological Department on Thursday declared the onset of monsoon in the national capital, two days earlier than the usual date of June 27.
The monsoon has further advanced into “some more parts of Rajasthan, remaining parts of Uttar Pradesh and Himachal Pradesh, entire Delhi, some parts of Haryana and most parts of Punjab”, the Met Department said.
Normally, the wind system reaches Delhi on June 27.
According to weather experts, the earlier than usual arrival of the monsoon in Delhi can be attributed to a cyclonic circulation over Bay of Bengal which moved towards southwest Uttar Pradesh on June 19 and June 20, helping monsoon advance further.
A trough line had been persisting for many days over Punjab, south Haryana, south Uttar Pradesh and West Bengal, which sped up the movement of monsoon, they said.
“There are two criteria to declare the arrival of the monsoon in Delhi — rainfall in the last 24 hours and wind flow pattern,” IMD Director General Mrutunjay Mohapatra said.
“Monsoon is declared in Delhi after both these factors are fulfilled,” he said.
Kuldeep Srivastava, the head of the regional forecasting centre of the IMD, said the northern limit of the monsoon now passes through Nagor, Alwar, Delhi, Karnal and Ferozepur.
Monsoon clouds had led to rains in some parts of the city on Wednesday but the Met Department had said the onset would be declared on Thursday.
Rainfall data from all weather stations for the last 24 hours ending 8.30 am is required to declare the onset of monsoon, Srivastava had said.
The Met Department also predicted heavy rainfall at isolated places in the national capital on Thursday.
Mahesh Palawat of Skymet Weather, a private weather forecasting service, said the monsoon has reached Delhi but the rains will remain subdued.
“We can expect light, patchy rains on Thursday evening and Friday. Dry weather will prevail on June 27 and 28,” he said.
Also read: Dengue, H1N1, leptospirosis — the monsoon challenges Kerala faces besides coronavirus