Longest heat spell for Delhi in 13 years: IMD

To put this number in context, 2022 clocked the most heatwave days till now, when 13 such days were recorded over March, April, May and June, officials said.

The Safdarjung observatory — representative of the Capital’s weather — has recorded 14 heatwave days since March 1, making it the highest count for such days in at least 13 years, the India Meteorological Department data available from 2011 onwards shows.

As far as data beyond 2022 is concerned, the years 2017 and 2014 recorded the most heatwave days in the corresponding period at seven each. (Vipin Kumar/HT)

Western disturbance rescues Delhi, breaks scorching day, night streak

To put this number in context, 2022 clocked the most heatwave days till now, when 13 such days were recorded over March, April, May and June, officials said.

IMD classifies it as a “heatwave” when the maximum temperature is over 40°C while also being 4.5 degrees or more above normal. However, 2023 did not record a single heatwave day in these four months, a sharp departure from what was observed in 2022, the data shows.

As far as data beyond 2022 is concerned, the years 2017 and 2014 recorded the most heatwave days in the corresponding period at seven each.

Temperatures were in control in March, April

This year, Delhi reported a substantial rise in the maximum temperatures despite pleasant weather conditions in March and April. The temperatures in these months were kept under check by frequent western disturbances. However, the temperatures rose after April, giving way to a spike in the number of heatwave days.

In 2022, heatwave days began as early as April, when nine such days were reported. This was followed by four in May 2022 and none in June, as pre-monsoon rain began to take over.

In 2017, six of the seven heatwave days in the summer were recorded in April, marking an early start to torrid days. In 2014, Delhi recorded its latest onset in terms of heatwaves, with all seven days occurring in June.

“This year, we recorded no heatwaves in March or April. Delhi managed below-normal temperatures on most days in these two months due to cloud cover and strong winds, as we recorded frequent western disturbances in those months. There was a change in the weather pattern by mid-May when western disturbances weakened in the region and clear skies were accompanied by dry westerly winds,” said an IMD official, adding that the absence of rain throughout summer has also been a factor behind such high temperature.

HT on June 8 reported that this was Delhi’s driest start to the year since 2018, with only 44.7mm of rain recorded at Safdarjung in the first five months of this year. This is only 42% of the long-period average of 104.8mm, which Delhi’s base observatory receives in the first five months of the year. The last time Delhi received less rainfall at the start of the year was 43.5mm in 2018.

May recorded five heatwave days this year, the highest in the last 13 years for the month. June has recorded nine heatwave days, also a record in this period for the month. IMD officials said data before 2011 was not readily available for heatwaves and will be analysed soon. “We will look at the trend for Safdarjung once the month ends,” said the official quoted above.

Light rains bring down temperature in Delhi amid severe heatwave; AQI improves

There was brief relief for residents on Thursday as strong winds and isolated drizzle took over after a spell of 11 consecutive days where at least one weather station in the city recorded a heatwave. Safdarjung recorded a maximum temperature of 40°C on Thursday, which was one degree above normal. It was 43.6°C a day earlier.