Delhi woke up yesterday wrapped in a thick grey smog, which is not expected to lift. The worrying air quality exceeds the World Health Organisation's recommended pollution levels by over 20 times.
However, this is not the only worrying news for those in the Indian city.
It seems this blanket of perpetual darkness is threatening the traditional celebrations for Diwali, the North Indian "festival of light".
The festival is traditionally marked by firework displays - but the use of firecrackers is expected to worsen the air quality.
In response, the Supreme Court has imposed an unpopular curfew for fireworks – restricting the window of celebrations to just two hours.
Earlier, an mooted ban on the sale of firecrackers was met with fiery resistance.
"Let's try out at least one Diwali without firecrackers," was the message from the Supreme Court Panel reported in The Hindu.
Diwali is a high point in the calendar for India's Hindu population.
It's also an important time for the tourism industry. Delhi occupies a central area in what is considered to be India's 'Golden Triangle' area and many international tour companies run Indian Diwali tours around this time, with the explicit purpose of seeing the country's exuberant light displays.
The country has seen an annual increase of almost 15 per cent for foreign tourist arrivals during the festive month of November.
For many, the proposed ban on fireworks fans the flame of divisions within the diverse population.
"Banning crackers on Diwali is like banning Christmas trees on Christmas and goats on Bakr-Eid. Regulate. Don't ban. Respect traditions," wrote the popular Indian novelist Chetan Baghat on Twitter.
A younger generation of Indians seem to be less nostalgic about the festival. Around 60 per cent of young Indians between 18-25 support the ban on firework sales.
The sale of "green firecrackers" which burn cleaner than traditional gunpowder fireworks have been encouraged to reduce the impact of the festival on air pollution.
The festival of Diwali represents the triumph of light over darkness, and good over evil.
Based in the Hindu texts describing the return of the deities Rama and Sita from exile, it is also observed by other major Indian religions. Sikhs, Jains and some Buddhists also celebrate the 'festival of light'.
Diwali comes from the Sanskrit word deepavali, meaning "rows of burning lamps", but today it is marked by burning fireworks as much as it is by traditional lamps.
It falls every year between October and November, following the lunar calendar around the darkest night.