Strong start: Monsoon brings season's first heavy rain spell in Delhi

The monsoon rolled into Delhi on Thursday, yielding the season's first spell of heavy rain which covered the precipitation deficit and brought the maximum temperature down to 29.4 degrees Celsius, the lowest in around four months.

Most parts of the city reported moderate to heavy rainfall. The Safdarjung observatory, Delhi's base station, recorded 116.6 mm downpour between 8:30 am and 5:30 pm.

The weather station at Lodhi Road gauged 107.6 mm precipitation during the same period. Ridge got 65 mm, Delhi University 58.5 mm, Pusa 44.5 mm, Palam 31.8 mm and Ayanagar 51.9 mm rainfall respectively.

Rainfall recorded below 15 mm is considered 'light', between 15 and 64.5 mm 'moderate', between 64.5 mm and 115.5 mm 'heavy', and between 115.6 and 204.4 'very heavy'. Anything above 204.4 mm is considered 'extremely heavy rainfall'.

The maximum temperature of 29.4 degrees Celsius was seven notches below normal and the lowest since March 6, when it had settled at 28.2 degrees Celsius.

The India Meteorological Department (IMD) said the southwest monsoon further advanced into Delhi, Uttar Pradesh, Himachal Pradesh, Jammu and Kashmiri, some parts of Punjab, Haryana and Rajasthan on June 30.

''The northern limit of the monsoon now passes through Deesa, Ratlam, Tonk, Sikar, Rohtak, Pathankot,'' it said.

The southwest monsoon usually arrives in the national capital on June 27 and covers the entire country by July 8.

Mahesh Palawat, vice-president (climate change and meteorology), Skymet Weather, said westerly winds had disrupted the monsoon's progress and it remained stalled over west Bihar for around eight to 10 days.

The Delhi-NCR is expected to get plentiful rainfall in July and August, he added.

However, Thursday's showers brought back familiar sights of serpentine queues of vehicles stuck on waterlogged roads.

Many commuters reported late for office and several people posted their plight through videos and photographs on social media, with some seeking help from police.

The IMD has issued an 'orange' alert, warning of moderate rainfall in the city on Friday. A 'yellow' alert is in place for light rain on the subsequent six days.

Last year, the IMD had forecast that the monsoon would arrive in Delhi nearly two weeks before its usual date. However, it reached the capital only on July 13, making it the most delayed in 19 years.

Weather experts say a gap of three to five days is considered normal.

According to IMD data, the monsoon covered Delhi 29 times in June and 33 times in July in the last 62 years.

The IMD had in 2020 revised the date of monsoon arrival in Delhi from June 29 to June 27.