Delhi ends June on sultry note, received excess rainfall of 228%

The India Meteorological Department (IMD) forecasted humidity to remain high throughout the week, despite issuing an orange alert — predicting moderate to heavy rainfall — till Saturday

Delhi ended June on a sultry note, recording no rainfall till late Sunday, even as it clocked 228% excess rainfall for the month, buoyed by the 228.1mm of rainfall recorded in the 24-hour period till 8.30am last Friday. The normal monthly average rainfall for June is 74.1mm.

Visitors at Kartavya Path. (Vipin Kumar/HT Photo)

On the whole, Delhi ended the month with a total rainfall of 243.4mm, its highest since 1936, when 415.8mm was recorded. This was also the third-highest June rainfall since 1901, with 399mm in 1933 being the second-highest.

Despite a forecast for moderate rain on Sunday, experts said the monsoon trough remained south of Delhi and could not provide any rain to the Capital. “The trough was expected to be over Delhi over the weekend, but it remained south of the Capital. From Monday, the trough will move north and will directly pass over Delhi. We are expecting good rain over Delhi on both Monday and Tuesday, before the trough moves to the foothills,” Mahesh Palawat, vice president at Skymet meteorology, a private forecaster, said.

Overcast skies gave way to bright sunshine throughout the day, making it uncomfortable to remain outdoors. The India Meteorological Department (IMD) forecasted humidity to remain high throughout the week, despite issuing orange and yellow alerts — predicting moderate to heavy rainfall — till Saturday.

High humidity levels of 60-97% took the wet-bulb temperature — an indicator of comfort level in the outdoors — to 30.1°C, the season’s highest. The previous highest wet-bulb temperature, of 30°C, was recorded on June 23.

The maximum temperature on the day was 37.1°C, normal for this time of the year, but the heat index or “real feel” temperature remained high, at 51°C at 5.30pm on Sunday. Delhi’s minimum temperature on Sunday was 27°C.

A wet-bulb temperature of 32°C or higher makes it difficult for even fit and acclimatised people to work outdoors for long and at a wet-bulb temperature of 35°C — the maximum threshold — humans can no longer regulate body temperatures, leading to heatstrokes and potential collapse.

The IMD’s Delhi forecast said: “Heavy rain is expected in the Capital on Monday, with thunderstorm and gusty winds of up to 30-40 km/hr. The maximum should be around 33°C and the minimum around 26°C.”

The monsoon hit the Capital last Friday, with 228.1mm of rainfall recorded in a 24-hour period till 8.30 am on Friday. In the next 24 hours, “trace” rainfall was recorded and in the subsequent 24 hours, 8.9mm was recorded till 8.30am on Sunday.

Delhi ends June on sultry note, received excess rainfall of 228%

IMD officials said rain activity is now expected in the early hours of Monday, which will again bring down temperature.

June was also a month of record heat, as Delhi logged a total of nine heatwave days, its highest in at least 13 years for the month.

Despite the rain in the tail-end, the average monthly maximum temperature for June was 41.9°C, nearly three degrees higher than the long-period average of 39°C. This was Delhi’s hottest June since 2012, when the average monthly maximum was 41.9°C.

The average monthly minimum temperature was 29.8°C, nearly two degrees higher than the long-period average of 27.7°C for June, making it the hottest June since 2012, when the average was 30.6°C.

Palawat said Delhi has not seen any significant pre-monsoon rain this month, with western disturbances missing in the first half of June. “In the second half, as the monsoon got closer to Delhi, there was more cloudiness and some light rain, but temperature has only dipped in the last week. The majority of the monthly rain has also occurred in just a single day, as opposed to light spells throughout the month, which keeps temperature in check,” he said.