Foggy morning in Delhi, minimum temperature at 7.1 degrees C

New Delhi: Delhiites woke up to another cold and foggy morning, as the minimum temperature in the national capital on Thursday was recorded at 7.1 degrees Celsius, the weather department said.

The Indian Meteorological Department (IMD) has issued a “yellow” alert for “dense fog” at isolated parts of the city and adjoining areas like Haryana and Chandigarh.

The maximum temperature is expected to hover around 15 degrees Celsius.

A spokesperson for the railways said that fog impacted the schedule of "24 trains approaching Delhi" due to low visibility.

The Palam Observatory, near the Indira Gandhi International Airport, reported a visibility level of 100 metres at 5:30 am. However, it improved to 500 metres by 7 am due to surface winds.

According to the weather office, "very dense" fog is when visibility is between 0 and 50 metres, between 51 and 200 metres is "dense", between 201 and 500 metres "moderate", and between 501 and 1,000 metres "shallow".

As per the data by the Central Pollution Control Board (CPCB), the overall Air Quality Index (AQI) at 9 am stood at 337.

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".

The relative humidity at 8.30 am was 96 per cent, the IMD bulletin said.