Light rain in Delhi, intensity likely to increase today

There are chances of light rain on Monday and moderate rain over most places till Thursday, IMD officials said

People in Delhi spent yet another day in muggy conditions, with the maximum temperature clocking in three degrees above normal at 37.5°C and humidity levels fluctuating between 60% and 82% on Sunday, when light showers later in the afternoon helped bring some relief.

Rain at Connaught Place on Sunday. (Sanchit Khanna/HT Photo)

The city’s wet bulb temperature -- which takes into account the high humidity that can hamper how the human body cools itself --- was an uncomfortable of 29.6°C by the evening. Wet bulb temperatures above 32°C can be dangerous, especially if someone is exerting themselves outdoors.

The India Meteorological Department (IMD) has predicted a gradual increase in rain activity over Delhi and the National Capital Region (NCR) from Monday as the monsoon trough moves closer to the region. “There are chances of light rain on Monday and moderate rain over most places till Thursday,” a Met official said on Sunday.

At 11.30 am on Sunday, Delhi had a relative humidity of 62% and an air temperature of 35.4°C. This resulted in a wet bulb temperature of 29.2°C and a heat index (HI) or “real feel” temperature of 47°C. The humidity was 70% and the temperature was 34.4°C at 5.30 pm, resulting in a wet bulb of 29.6°C and an HI of 48°C. The humidity data for 2.30pm, when it is typically the hottest outside, was unavailable.

HI and wet bulb are both used to indicate how uncomfortable it is to be outside, with the former indicating the actual feel of the temperature outside on human skin when humidity is considered.

On Saturday, the highest HI was 50°C, and the highest wet bulb reading was 29.9°C.

According to IMD data, Safdarjung, representative of Delhi’s weather, recorded 0.2mm of rainfall between 8.30 am and 5.30 pm on Sunday. Lodhi Road (1mm) and Pusa (6.5mm) were the other stations that recorded rain in the Capital. Meanwhile, Delhi’s minimum (night) temperature was 28.9°C, two degrees above normal.

According to IMD’s forecast, the day and night temperatures are expected to remain around 37 and 28°C, respectively, on Monday. As the rain intensifies on Tuesday, they will fall to 34 and 26°C, respectively.

In terms of air quality, Delhi’s air quality index (AQI) has remained satisfactory. On Sunday, the 24-hour average AQI was 73 (satisfactory), an improvement over 95 (satisfactory) the day before. The Early Warning System (EWS) for Delhi, a forecasting model run by the ministry of earth sciences, predicts that AQI will remain satisfactory until Wednesday.