IMD predicts widespread rain in Delhi, monsoon deficit drops

Data shows that the Safdarjung Observatory, representative of the national Capital’s weather, observed a rainfall surplus of 8.9%, Palam received a surplus of 7.2% and Lodhi Road received a rainfall surplus of 19.1% between June 1 and August 17.

After beginning on a shaky note, Delhi has managed to reduce the rainfall deficit recorded this monsoon to 14% from 23%. India Meteorological Department (IMD) data shows that between June 1 and August 18, Delhi has recorded cumulative rainfall of 342.9 mm.

Scientists at IMD said that even though the monthly rainfall statistics for August still show a 23% deficit, there is a forecast of heavy rain on August 18, 19, and 20, and the deficit could well be covered in the next few days. (Ajay Aggarwal /HT PHOTO)

However, the city is expected to cover the deficit in the next two days as IMD has forecast moderate to heavy rainfall.

Delhi starts recording monsoon rain from June 1 and September 30 is considered the monsoon retreating date.

Officially, monsoon’s arrival in Delhi was declared on July 24.

Parts of the national capital on Tuesday received moderate rainfall. IMD data shows that areas around west and southwest Delhi received 2.4 mm rainfall, while central and south Delhi received trace rain.

Intermittent showers were reported from Dwarka, Janakpuri, Palam, Uttam Nagar, Rajouri Garden and Tilak Nagar, starting Tuesday afternoon. The IMD forecast said that the intensity of the rain is expected to increase and a spell of heavy rain is likely in the capital on Tuesday night.

The IMD said that these heavy spells of rainfall is likely to continue till Thursday. This, the weather scientists said, will cover the cumulative rainfall deficit that the city has recorded in the month of August. Data shows that after Tuesday’s rain, the monthly rainfall recorded in the month of August touched a surplus of 3%.

“Under the influence of a large cloud cluster approaching from southwest direction, rainfall started over west and southwest Delhi. This cluster contained clouds with reflectivity as high as 50 dBz. By Tuesday night, wind speed is also likely to reach 40-50 kmph over parts of south, central and west Delhi,” an advisory released by the IMD read on Tuesday.

Reflectivity in decibel relative to Z is a radar measurement used to estimate intensity of rain or snowfall.

Kuldeep Srivastava, head of IMD’s regional weather forecasting centre, said in the coming two days rainfall activity is expected to increase throughout the city.

“Tuesday’s rain was mostly concentrated in parts of west and southwest Delhi, but from Wednesday, we will see moderate to heavy rains across the city,” Srivastava said.

IMD data of rainfall recorded in August shows that parts of northeast Delhi, south Delhi and central Delhi have a deficit ranging between 20-40%. However, areas around northwest Delhi, southwest and west Delhi have received surplus rainfall ranging between 10-48%, making up for the rest of the city.

“We are expecting that the overall deficit will be covered in the coming three days,” said Srivastava.

IMD data also shows that till July 16, Delhi had a rainfall deficit of 46%, but by July end it was reduced to 29%. The IMD forecast also shows that this season Delhi is likely to record normal or surplus rainfall. Between June 1 and August 18, Delhi

In 2019, the monsoon season retreated in Delhi on October 10, with a rainfall deficit on nearly 38%. The city, however, witnessed surplus rainfall in 2018 and 2017, with 770.6mm and 672.3mm rain respectively. The IMD had recorded 524.1mm rainfall in 2016 as against the city’s average of 648.9mm and 515.3mm in 2015. The city had gauged 370.8 mm rainfall in 2014.