Delhi woke up to moderate fog on Monday morning, with the minimum temperature at 7.6 degrees Celsius, though the city is likely to experience a relatively warm day as the maximum temperature is forecast to hover around the 24-degree mark.
Sunday’s maximum of 24 degrees Celsius was three notches above normal; the minimum temperature yesterday was clocked at 8.2 degrees Celsius.
The India Meteorological Department (IMD) had forecast light drizzle over Delhi from Tuesday till January 26, with no cold wave conditions expected till at least January 28.
“We are seeing two back-to-back western disturbances in the region and while the impact of the first western disturbance is over, this second western disturbance will impact the northern plains mostly between January 24 and 26, when a drizzle is expected. Some parts may also receive very light rain,” said a met official, stating that the intensity of rainfall is also expected to be less as compared to previous forecasts.
“The western disturbance trough is advancing forward and likely to turn into a cyclonic circulation, which can cut down the moisture. Therefore, we are expecting less impact over Delhi NCR,” the official added.
Cold wave conditions in Delhi abated January 19 onwards, with the minimum temperature remaining above 5 degrees since. Delhi in January has already recorded two severe cold wave spells, the first between January 5 and 9, and the second between January 16 and 18.
The IMD classifies the conditions as ‘cold wave’ when the minimum temperature is 4.5 degrees or more below the normal mark, or when it drops to 4 degrees or lower.
Meanwhile, the western disturbance reduced the wind speed in the national capital on Sunday and led to a deterioration in air quality, prompting the Commission for Air Quality Management (CAQM) in NCR and adjoining areas to hold an emergency meeting in the evening. However, it decided not to invoke measures under Stage-III of the Graded Response Action Plan (GRAP), stating forecasts showed Delhi’s air quality index (AQI) was likely to improve once again from Monday.
The air quality on Monday morning dropped to the ‘very poor’ category from ‘severe’ a day ago as Delhi recorded an AQI of 357 at 8 am today, a dip of 50 points compared to the 4 pm reading of 407 on Sunday, according to the Central Pollution Control Board’s bulletin on Sunday. Winds are expected to pick up further in the next 24 hours, facilitating further dispersal of pollutants, officials said.
Stage-III of Grap is generally invoked when the AQI is predicted to cross 400, or has already crossed that threshold. However, the decision is generally taken by the CAQM sub-committee on Grap. Under Stage-III, private construction activities across Delhi-NCR are put on hold, while brick kilns and hot mix plants not operating on clean fuels are also shut down. Further, all stone crushers and mining or its related activities are stopped if Stage-III is invoked. The Delhi government also has the option to ban BS-III petrol and BS-IV diesel vehicles from plying in the national capital.
