The Indian Meteorological Department (IMD) issued an orange alert for fog in Delhi on Monday. Since Sunday, Delhi has seen a slight fall in maximum temperatures over Delhi/NCR. According to IMD, this week the maximum and minimum temperatures over Delhi are in the range of 28 to 30 degrees Celcius and 12 to 17 degrees Celcius respectively.


However, the IMD reported that the maximum temperature was above normal by 1 degree Celcius and the minimum temperature was above normal by 4 degrees Celcius in most places.


For Monday, Delhi has forecast mainly clear sky with wind from the northwest direction with speed of less than 6 kmph during morning hours which will gradually increase to 10 kmph from northwest direction during afternoon. Smog/moderate to dense fog is likely in the morning. It winde speed will lower to 8 kmph in evening and night. Smog/ shallow fog is likely in the evening/night


As per the report, smog or moderate to dense fog is likely in the morning and is expected to lessen in the evening and night. The national capital has reported the worst air quality of the season as the air quality index (AQI) was recorded at 484 at 9 am on Monday. An AQI between zero and 50 is considered "good", 51 and 100 "satisfactory", 101 and 200 "moderate", 201 and 300 "poor", 301 and 400 "very poor", and 401 and 500 "severe".


According to IMD, the dense fog contains particulate matter and other pollutants and in case exposed it gets lodged in the lungs which can potentially clog them, decrease the functional capacity of the lungs and increase episodes of wheezing, coughing and shortness of breath.


For people with asthma bronchitis, long-time exposure to the dense fog may increase their respiratory problems. The pollutants in dense fog contain various types of pollutants in the air, if exposed it may tend to irritate the eyes causing various infections leading to redness or swelling of the eye. 


Private carrier IndiGo on Sunday night said fog is affecting visibility in the national capital which could delay flight schedules, while Delhi airport operator DIAL has put in place low visibility procedures. The national capital is grappling with high pollution levels which have resulted in lower visibility at various parts of the city.