Delhi, north India reel under intense cold wave, spell to continue till New Year
Delhi woke up to a chilly morning on Thursday as a severe cold wave swept through entire northern India with a forecast of a likely cold or severe cold day conditions for the next five days in many states.
The Capital, which is experiencing the longest cold wave in December in 22 years, recorded a “severe” cold day on Wednesday with the maximum temperature dropping to 12.7º Celsius, nine degrees below normal. The minimum temperature was 6ºC, two degrees below normal.
The minimum temperature on Wednesday night was recorded at 6 degrees Celsius and the weather bureau said it was 7 degrees Celsius at 5:30 am on Thursday.
Since 1993, Delhi has had a cold spell only in four years—1997, 1998, 2003, and 2014.
Most stations in Delhi, except Safdarjung, have recorded a cold spell for 12 days in a row. At Safdarjung, the cold was eight days till Monday.
RK Jenamani, a senior scientist at the National Weather Forecasting Centre, said the lowest day temperature for Delhi was recorded on December 28, 1973, at 11.2ºC. This year till now the lowest day temperature is 12.2º C on December 17.
The intense cold spell will continue till at least till December 27.
The Centre-run System of Air Quality and Weather Forecasting (SAFAR) suggests a slight improvement in wind speed and ventilation, and a marginal improvement in Air Quality Index (AQI) is forecast for Thursday but within the very poor category.
“From Friday onwards winds are forecast to slow down for three days. On Friday the AQI is forecast to deteriorate towards the higher end of the very poor category. The dense fog in the morning hours is likely to continue for the next two days under favourable meteorological conditions,” SAFAR said.
It also predicts that low surface wind speed and low ventilation are forecast for an extended period from Friday and likely to lead to the accumulation of pollutants. By December 29, the AQI is likely to touch higher levels, it said.
Officials had said the severe cold conditions will prevail till the end of 2019 and the minimum temperature will show a minor increase in the New Year on January 1 and 2. They predicted dense foggy conditions during morning hours for another week.
Authorities have shut schools and colleges in Haryana, including Gurugram, Agra and Ghaziabad in Uttar Pradesh as the intense cold spell, which impacted the entire northern region last week, is likely to continue this week.
The “cold wave” conditions are predicted to set in over Delhi and neighbouring states of Punjab, Haryana, Chandigarh and Uttar Pradesh, the India Meteorological Department (IMD) has said.
IMD says a “severe cold day” is registered when two things happen — the minimum temperature drops to less than 10 degrees Celsius and the maximum temperature is at least 6.4 degrees Celsius below normal.
And a “cold day” is registered when the minimum temperature is less than 10 degrees Celsius and the maximum is 4.4 degrees Celsius below normal.
Meteorologists say the unusually cold conditions are due to a western disturbance (WD), which brought heavy snowfall in the Himalayan region — Uttarakhand, Jammu and Kashmir and Himachal Pradesh — and rainfall across the northern plains, including in Delhi on December 12 and 13.
That western disturbance had left a lot of moisture in the atmosphere. Cold northwesterly winds and high relative humidity is causing dense fog in the morning hours.
“After sunrise when the surface warms a little the fog layer lifts up but not enough. It continues to hang close to the surface in the form of a low cloud cover. This is the main reason sun is not able to warm the surface and day temperature is low,” Kuldeep Srivastava, head of the Regional Weather Forecasting Centre, explained.
Scientists had said that cold wave conditions are likely to develop over Punjab, Haryana, Chandigarh, Delhi and north Rajasthan on December 25. It also said cold day to severe cold day conditions are likely over Punjab, Haryana, Chandigarh and Delhi during the next two to three days.
“After 25th, we are expecting clear skies, low wind speed which will cause nighttime temperature to fall significantly. It is mainly because of radiational cooling when ground radiates heat away at night. The relative humidity is also high so there may be dense fog also in the morning hours,” Srivastava said.
“When a western disturbance moves away, there is cold air incursion from the higher reaches of northwest India. There are usually clear skies and very cold nights, the combination of these conditions brings on a cold wave,” said K Sathi Devi, head of National Weather Forecasting Centre.
Cold wave continued to sweep most parts of Haryana and Punjab, with Narnaul reeling at a minimum temperature of 3.2 degrees Celsius on Wednesday.
Narnaul in Haryana was colder by two degrees against normal limits. Hisar too recorded below normal minimum temperature at 4.1 degree Celsius, weather officials said.
A meteorological department official said severe cold weather conditions are likely to continue for the next two days in Haryana.
Punjab’s Faridkot was the coldest place recording a low of 4.6 degree Celsius. Chandigarh, the common capital of the two states, recorded a low of 6.9 degree Celsius.
Isolated places in Uttar Pradesh received light rain and the cold wave continued unabated across the state on Wednesday, the meteorological department said.
It said most places in the western and eastern part of the state remained under the firm grip of intense cold wave.
On Thursday, the weather is likely to remain dry with fog enveloping several parts of the state. Similar weather conditions are likely to prevail in the state till December 28, the met office said.
Cold wave continued in parts of Rajasthan where Sikar was the coldest place, recording a minimum temperature of 2.5 degrees Celsius on Wednesday. The weather conditions would remain the same during the next 48 hours, weather officials said.