Delhi on Wednesday recorded 60 mm rainfall till 8:30 pm, the highest 24-hour precipitation in May in 35 years, under the impact of cyclonic storm 'Tauktae' and a western disturbance, the India Meteorological Department said.
The city also recorded a maximum temperature of 23.8 degrees Celsius, 16 notches below normal and the lowest in the month of May since 1951, the IMD said.
The capital had recorded 60 mm rainfall in a 24-hour period on May 24 in 1976.
The rainfall in Delhi, Uttar Pradesh, northern Rajasthan, Himachal Pradesh and Uttarakhand on Wednesday is a result of interaction between the remnant of cyclonic storm "Tauktae" and a Western Disturbance, the IMD said.
The Safdarjung Observatory, which provides representative figures for the city, recorded 60 mm rainfall between 8:30 am and 8:30 pm, the IMD said.
"There has been more rain after 8:30 pm. So, the record has already been broken," R K Jenamani, senior scientist, national weather forecasting centre, said.
"May remains generally dry. Normally, Delhi gets maximum of 30 mm or 40 mm (24-hour rainfall) in this month. The rain lasts only an hour or less. But this is completely different system coming from Arabian Sea and meeting with a Western Disturbance. Because the feature is rarest, so crossing 60 mm is no surprise," he said.
Palam, SPS Mayur Vihar and Najafgarh recorded 36.8 mm, 39.5 mm and 57 mm rainfall during the period.
Rainfall recorded below 15 mm is considered light, between 15 and 64.5 mm is moderate, between 64.5 mm and 115.5 mm is heavy, between 115.6 and 204.4 is very heavy. Anything above 204.4 mm is considered extremely heavy rainfall.
The IMD said "rainfall activity is very likely to decrease" on Thursday and "scattered to fairly widespread" rainfall is forecast in the capital.
The incessant rains brought the maximum temperature down to 23.8 degrees Celsius at Safdarjung. The minimum temperature settled at 21.4 degrees Celsius, five notches below normal.
"Today, Safdarjung recorded a maximum temperature of 23.8 degrees Celsius. This is the lowest maximum temperature since 1951," Kuldeep Srivastava, the head of the IMD's regional forecasting centre, said.
In between, a low of 24.8 degrees Celsius was recorded on May 13 1982, he said.
The maximum temperature dipped to 22.6 degrees Celsius at Jafarpur and Mungeshpur.
According to the IMD, Delhi's maximum temperature during the day was less than that of Srinagar (25.8 degrees Celsius) and Dharamshala (27.2 degrees Celsius) up in the north.
Delhi recorded its air quality in the 'satisfactory' category for the second consecutive day on Wednesday due to rainfall and strong winds, according to Central Pollution Control Board data.
The city had recorded a 24-hour average air quality index (AQI) of 78 on Wednesday. It was 93 on Tuesday.
An AQI between 201 and 300 is considered poor, 301-400 very poor and 401-500 severe, while an AQI above 500 falls in the severe plus category.
