Relief nears end; IMD says heatwave ahead
A cyclonic circulation in Delhi has dissipated, leading to rising temperatures and a heatwave alert for April 16-17, while air quality may worsen.
A cyclonic circulation that led to a sudden drop in temperatures in Delhi has dissipated, India Meteorological Department (IMD) officials said on Sunday. The Met has forecast the temperature to keep rising over the next week, with a yellow alert in place for April 16 and 17, warning people of possible heatwave conditions.
Delhi’s pollution levels, meanwhile, continued to stay in the “moderate” zone for a third consecutive day on Sunday, but the air quality is likely to deteriorate to the “poor” zone on Monday, officials said.
According to IMD, a heatwave is when the maximum temperature is above 40°C, while the departure from normal is 4.5°C or more. It is also a heatwave if the maximum is over 45°C in the plains. IMD calls it a “severe heatwave” when the maximum is above 40°C, and the departure is 6.5°C or more above normal.
Delhi has already recorded three heatwave days this month — on April 7, 8, and 9 — but this three-day streak was snapped after a western disturbance began affecting northwest India from April 10, Thursday. By Friday evening, the western disturbance had triggered a sudden and violent storm that swept across Delhi and the National Capital Region (NCR), leaving behind a trail of destruction that claimed three lives and knocked down dozens of trees, power poles, and even buildings and walls, bringing life to a standstill across the region.
The dust storm, intense winds of more than 80 km/hr, and short but fierce rain showers led to a sharp drop in temperature, with relatively cool conditions on Saturday as well.
By Sunday, the mercury began to rise. The maximum temperature at the Safdarjung observatory — Delhi’s base weather station — was 36.6 degrees Celsius (°C), which was half a notch above the normal for this time of the year, and 1.4°C above the 35.2°C recorded on Saturday.
Other parts of the city were cooler — it was 34.3°C at Rajghat, 34.4°C at Pusa, 35.2°C at Najafgarh, and 35.9°C at Ayanagar. The warmest station in Delhi was Ridge at 37.3°C.
The minimum, meanwhile, was 20.4°C, which was half a degree below the normal but 1.2°C above the 19°C logged the previous day.
The storm on Friday also played havoc with air travel — flight operations were suspended for an hour due to safety concerns, leading to hundreds of flights getting delayed. These delays also spilled over to Saturday, but airport officials on Sunday said that the traffic had now cleared up.
IMD attributed the slight uptick in temperature on Sunday to the cloudy conditions in the Capital. The Met has forecast the maximum temperature to be around 38-40°C on Monday and reach 40-42°C by Wednesday. A heatwave warning has been issued for Wednesday and Thursday.
“Partly cloudy skies were observed on Sunday, but mostly clear skies are expected from Monday. Easterly or south easterly winds of speed up to 22 kmph prevailed over Delhi-NCR… Maximum temperature is expected to cross 40°C in the coming week, with possible heatwave conditions in the middle of the week. Strong surface winds of speed 20-30 kmph are also likely to influence the Capital and neighbouring areas from Tuesday,” said an IMD official.
“A fresh western disturbance is likely to affect the western Himalayan region from April 16, the impact of which might extend to the northern plains,” the official added.
The minimum temperature, according to IMD forecast, is expected to be around 21-23°C on Monday.
AQI set to deteriorate
Delhi’s air quality on Sunday continued to stay in the “moderate” category for a third consecutive day, with a 24-hour average air quality index (AQI) reading of 178 at 4pm on Sunday, according to the Central Pollution control Board’s (CPCB) daily national bulletin. The AQI was 166 (moderate) at the same time on Saturday, and 164 (moderate) on Friday.
However, according to the forecasts by Air Quality Early Warning System (AQEWS) for Delhi, the AQI is expected to deteriorate to the “poor” zone by Monday.
“The air quality is likely to be in the ‘poor’ category from Monday to Tuesday. The air quality is likely to be in the moderate category on Wednesday. The outlook for the subsequent six days is that the air quality is likely to be in the moderate to poor category,” the bulletin said on Sunday evening.
