Heavy rainfall continued to lash parts of Delhi-NCR on Thursday, disrupting normal life with waterlogging, traffic congestion and inundated roads, while Delhi Chief Minister Rekha Gupta reviewed drainage arrangements in one of the affected areas.
As of Thursday afternoon, boats were seen navigating waterlogged streets in Ghaziabad's Vasundhara, high-rise buildings in Noida were shrouded in clouds, and long traffic snarls were reported from Gurugram and several parts of New Delhi.
According to meteorologists, East Delhi, Noida, Ghaziabad and Faridabad received the heaviest rainfall between Wednesday night and Thursday morning, while west and central Delhi and Gurugram witnessed comparatively lighter showers.
What's Driving The Heavy Rain?
Weather experts attributed the widespread rainfall to an active low-pressure area and the seasonal monsoon trough.
According to private forecaster Skymet Weather, "The monsoon has finally gained strength in Delhi-NCR... due to the influence of an active low-pressure area and the monsoon trough, there is a possibility of intermittent rain continuing until July 10."
A low-pressure area develops when surface air pressure falls below that of the surrounding region, causing air to converge and rise. As the rising air cools, moisture condenses into clouds, resulting in rainfall.
The India Meteorological Department (IMD) describes a low-pressure area as being "associated with a whirling motion of air, convergence and upward motion of air. In the low, usually clouds and rainfall are present."
In its 9:15 am bulletin on Wednesday, the IMD said a well-marked low-pressure area was located over northeast Madhya Pradesh and adjoining southeast Uttar Pradesh, with the seasonal monsoon trough extending from southwest Rajasthan to Bangladesh. The system has since moved close enough to influence weather over Delhi-NCR.
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Role Of The Monsoon Trough
The monsoon trough is an elongated belt of low pressure that stretches across northern India during the southwest monsoon season.
Often described as the backbone of the monsoon, it provides a pathway for weather systems such as low-pressure areas and depressions that bring widespread rainfall.
The IMD describes the monsoon trough as "one of the semi-permanent features of monsoon circulation." Its position determines where the heaviest rainfall occurs. When it shifts south of its normal position, northern and central India, including Delhi-NCR, receive enhanced rainfall. When it moves closer to the Himalayan foothills, rainfall decreases over the plains in what is known as a "break" in the monsoon.
According to Skymet Weather, Thursday's rainfall was triggered by the favourable positioning of the monsoon trough along with the well-marked low-pressure system moving along it.
CM Rekha Gupta Reviews Drainage Measures
Amid the heavy rainfall, Delhi Chief Minister Rekha Gupta inspected drainage arrangements in Shalimar Village to review measures aimed at addressing waterlogging.
She issued directions to officials present at the site to ensure the proper drainage of accumulated rainwater.
According to the Chief Minister's Office (CMO), the Delhi Government and all concerned departments are working with "great promptness" to tackle waterlogging caused by the ongoing monsoon rains.