Delhi is set to experience isolated cold day conditions this week as shallow fog envelopes the region, bringing a noticeable chill across the city, while the air quality shows marginal improvement from previous days. On Wednesday, residents can expect frigid temperatures during the day, with the maximum temperature likely to range between 12°C and 15°C at Safdarjung and 10°C–14°C at Palam. Minimum temperatures are expected to remain low, around 3°C–4°C, though slightly above levels recorded during the harsh 2019 winter.

Weather Observations and Temperature Trends

On Tuesday, Delhi’s Safdarjung observatory, which represents the city’s weather conditions, recorded a maximum temperature of 15.7°C, three degrees below the seasonal average, while Palam logged 13°C. The minimum temperature at Safdarjung dropped to 7.6°C. At least two stations reported cold day conditions, as the mercury stayed persistently below the comfort level for northern India.

A “cold day” is defined by meteorologists as when the minimum temperature falls below 10°C and the departure from normal is 4.5°C or more, while a “severe cold day” occurs when the maximum temperature is 6.5°C or more below normal. In the recent past, Delhi recorded record lows, including 14.2°C on December 31, 2025, the lowest maximum in six years, and an even more historic drop to 9.4°C on December 30, 2019 — the coldest December day in 119 years.

Fog and Wind Dynamics

Shallow upper-level fog persisted on Wednesday, reducing visibility to around 800 meters at Safdarjung and Palam. Fog at higher levels often traps heat during the night, raising minimum temperatures, but simultaneously blocks sunlight during the day, keeping maximum temperatures low. This combination produces a narrow but bitterly cold window between the daily maximum and minimum.

Navdeep Dahiya, an amateur weatherman tracking Delhi’s winter trends, explained the chilly conditions: “For Delhi, we can expect maximum temperatures to remain in the 12-15°C range at Safdarjung over the next nine to ten days and 10-14°C at Palam. The minimum may not fall as low as during 2019, but it should still hover around 3-4°C. Early morning fog will continue, persisting in mid-and-upper levels during the day.”

Dahiya noted that icy-cold northwesterly winds sweeping across the region exacerbate the chill, lowering the “felt” temperature during the day despite the presence of fog. “Despite fog, which keeps the minimum temperature slightly higher, these winds keep the maximum temperature suppressed and gradually push the minimum lower,” he said.

Air Quality Improvement

While the cold grips the city, residents can expect a slight relief from pollution. The 24-hour rolling average Air Quality Index (AQI) at 9 am on Wednesday was recorded at 300, classified as “poor,” improving from 310 (“very poor”) at 4 pm on Tuesday. However, the AQI is expected to remain in the very poor range until Friday, indicating that while there is minor improvement, the air continues to pose health risks, particularly for sensitive groups such as children, the elderly, and those with respiratory conditions.

Regional Weather Factors

Delhi’s current cold spell is part of a broader north Indian winter pattern, where dense fog and cold northwesterly winds combine to bring persistent chill. Upper-level clouds and fog reduce daytime heating, while clear nights allow radiational cooling, dropping night-time temperatures. This combination has resulted in single-digit night temperaturesin parts of the Indo-Gangetic plains and frigid daytime temperatures in the city.

The India Meteorological Department (IMD) has not officially declared “cold day” conditions for all locations in Delhi on Tuesday, but experts like Dahiya point to the perceived chill created by wind and fog, which makes the cold feel more intense than the actual recorded temperatures.

Looking Ahead

The cold spell in Delhi is expected to persist until mid-January, with maximum temperatures unlikely to rise significantly due to ongoing fog and icy northwesterly winds. While Delhians experience bone-chilling mornings and relatively mild afternoons, the early morning fog may reduce visibility and affect traffic, especially on arterial roads connecting the city to the suburbs and neighboring states.

Experts advise residents to dress in layers, limit exposure during the coldest hours, and take precautions against respiratory issues as air pollution, though slightly improved, continues to pose health risks.

In summary, Delhi is bracing for a persistent cold phase with isolated cold day conditions and intermittent fog, as maximum temperatures hover in the low teens and minimums stay near 3-4°C, while air quality slightly improves but remains a concern. With the combination of fog, icy winds, and below-normal mercury, residents should prepare for one of the coldest periods in the city this winter.

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