Delhi–NCR Winter 2025:
A full in-depth explanation of the unusually warm winter.

Ordinarily, as December progresses, the onset of sharp temperature drops starts, along with foggy mornings and cold winds from the Himalayas, in Delhi–NCR. However, this winter was taking a different turn-being warm, delayed, and milder than the historic averages. Current temperatures were running 2-4°C above normal, with fewer cold-wave days and significantly reduced fog.

The causes, which have to do with weather, climate science, and geographical changes, can be considered in detail as part of greater global warming trends.

Weak Western Disturbances- Main Cause:

Western Disturbances (WDs): These are winter storms originating from the Mediterranean region, causing:

Cold winds

Rain in North India

Drop in minimum temperatures

This year:

WDs have been weak, infrequent, and passing too far north.

Due to this, the cold air from the hills does not strongly push into the plains.

Similarly, Kashmir and Himachal receive below-normal snowfall, thereby reducing the cooling effect on the Indo-Gangetic plains.

Result:

The capital has also not received the “cold shock” that marks true winter onset.

2. Warmer Winds from Rajasthan & Central India

Normally, immediately after WDs pass, cold winds sweep down from the northwest.

But this year:

Dry, warm winds from Rajasthan dominate.

Even Central India records above-normal temperatures.

These are warm winds that are preventing the temperature from plunging during nights.

Delhi’s minimum temperatures are remaining high because the region is not in isolation from surrounding heating zones.

????️ 3. Increasing Urban Heat Island (UHI) Effect

Cities like Delhi trap heat because of the following reasons:

It considers reinforced concrete buildings.

Asphalt roads

High Vehicle density

Industrial activity

Density of population

This results in the effect of an Urban Heat Island, whereby the metropolitan regions continue to remain notably warmer when compared to the neighboring rural areas.

2025:

Construction activity has increased.

Emissions from vehicles are on the high side.

Nighttime heat escape is reduced.

Therefore, evenings and nights are still unusually warm.

☁️ 4. Less Fog = Less Cooling

Fog cools the surface by intercepting sunlight.

But this year,

Fog events are far fewer

Skies are clearer for longer

Sunlight heats the ground more than it usually does.

Less fog → More warming → Slower onset of winter feel.

???? 5. Global Warming + El Niño Impact

Global climatic patterns now strongly influence India’s winter.

A. Global Warming Trend

Worldwide, temperatures are rising on average. This creates:

Warmer Oceans

Warmer land masses

Weaker cold spells globally

The consequences are being felt directly by India.

B. Lingering El Niño Influence

El Niño causes:

Warmer Asian Winters

Disturbed wind patterns

Weakened high-pressure systems that often advance cold waves

These combined effects are the reasons North India is receiving less cold air advection.

6. Below Normal Snowfall Recorded in Himalayas

A good winter chill over Delhi depends on:

Heavy snowfall in Jammu & Kashmir

Strong cold winds blowing from hills towards planes

But this year:

Snowfalls during November and the early part of December were much lower.

Meanwhile, temperatures in hill stations like Shimla, Srinagar, and Manali remained above normal.

Cold winds stayed trapped in the upper atmosphere.

In case the mountains do not cool down sufficiently, the cold waves are not experienced in the plains.

7. Longer-than-Usual Post-Monsoon Heat

The post-monsoon period was hotter for longer in 2025 during Oct–Nov because:

Monsoon withdrawal was late.

More humidity was left in the air.

It didn’t cool the land sufficiently fast before winter.

This created a sort of “warm base” for December temperatures.

Air Pollution’s Mixed Effect Additional resources will be needed to reduce the pollutants being emitted by manufacturing or increased alternative energy production.

It is due to pollution that:

Smog has a heating effect because it acts as a heat trap.

• A cooling effect when it blocks sunlight

But this year,

Smog episodes were less frequent during this winter compared to the previous winters.

Hence, the heavy smog had little cooling effect.

The warming effect of trapping the heat continued.

This combination added to the delayed winter chill.

Down: 9. Historical Context – How Different Is This Year?

Delhi often witnesses:

5–6°C minimums by early December

Severe cold waves from mid-December

Dense fog spells persisting for days together

In 2025:

The minimums remain around 10–15°C.

Yet no major wave of cold has formed.

Fog frequency is well below seasonal averages

That makes winter start with the one of the warmest beginning in more than ten years.

???? 10. Where’s the Real Winter?

Meteorologists say:

Stronger Western Disturbances are likely to reach here after mid-December.

Cold wave conditions may be seen late in December.

This means that January could still see sharp drops, but the winter as a whole may be shorter and milder.

Expect:

2–3 severe cold snaps
Short periods of heavy fog
A quick return to warmer temperatures
Winters are changing over a gradual time in Delhi, not long cold months of unrelenting continuous cold but rather short and intense.
Summary: Why Winter Is So Mild in Delhi–NCR
Factor Effect
Weak Western Disturbances × No cold air push
Warm winds from Rajasthan High minimum temperatures Urban Heat Island Extra radiant heat trapped Fewer fog events occur More solar heating El Niño + global warming are shown to lead to a hotter-than-usual season. Less snowfall in the Himalayas, there won’t be any powerful cold waves Above normal post-monsoon warmth to continue; delayed winter setup