Worst Time to Visit Delhi: Heat, Smog, Fog & Monsoon
Every site tells you the best time to visit Delhi. A Delhi-born guide tells you the months to avoid, and why, with official data.
Short answer: May and June are the worst, then the monsoon, November smog and winter fog
Every guide tells you when Delhi is best. We will tell you when to think twice.
- Worst: May and June. Average daytime highs are about 41°C in May and 40°C in June, according to the India Meteorological Department (IMD).
- Poor: July and August. Heavy rain and humidity. These are Delhi's two wettest months.
worst-time-to-visit-delhi - Poor: November. Smog from stubble burning, firecrackers and cold, still air. Early November 2025 readings were "very poor".
- Poor: late December and January mornings. Fog can cancel flights and delay trains.
The months in between, mainly February, March and the weeks either side of the worst periods, are the easy ones. If you must choose between bad months, the rest of this page explains each one.
Delhi month by month: weather figures and our verdict
The first four columns are the IMD's long-term averages for New Delhi (Palam station, 1991 to 2020). The last two are our own view as Delhi guides, using the sources in the sections below.
| Month | Avg low / high (°C) | Rain (mm) | Fog days | Main problem | Our verdict |
|---|---|---|---|---|---|
| January | 7.3 / 19.9 | 17.2 | 20.7 | Cold mornings, fog, crowds | Fair, with fog risk |
| February | 10.6 / 24.1 | 18.8 | 13.1 | Little | Good |
| March | 15.4 / 30.0 | 11.0 | 6.0 | Warming up | Good |
| April | 21.7 / 37.1 | 10.7 | 0.5 | Heat starts | Poor |
| May | 26.4 / 40.7 | 32.9 | 0.1 | Extreme heat | Worst |
| June | 27.9 / 39.6 | 75.2 | 0.7 | Heat and humidity | Worst |
| July | 27.4 / 36.0 | 188.7 | 0.2 | Monsoon rain, humidity | Poor |
| August | 26.4 / 34.5 | 197.9 | 0.3 | Wettest month | Poor |
| September | 24.9 / 34.4 | 117.4 | 0.7 | Humid, rain easing | Fair |
| October | 19.9 / 33.3 | 12.6 | 2.3 | Pleasant, but smog season starts to build | Fair |
| November | 13.7 / 28.3 | 3.8 | 7.3 | Smog | Poor |
| December | 9.0 / 22.7 | 5.8 | 15.4 | Fog and cold | Fair, with fog risk |
"Fog days" is the number of days per month with fog recorded at the station. Weather varies by year, so treat every row as a pattern, not a promise.
April to June: the heat
According to the IMD, the average daytime high in Delhi is about 37°C in April, 41°C in May and 40°C in June. Nights stay warm too: the average low in May and June is above 26°C.
From our own work: the heat from April to August is hard on guests. Between about 10 am and 12 noon many of them struggle. We have seen red skin, tiredness and nosebleeds. Our advice to guests is plain: do not come in summer if you can choose.
If you cannot avoid it, start at sunrise, do one main sight a day, rest indoors in the middle of the day, and drink water often.
July to September: monsoon and humidity
The IMD's long-term figures show July and August as Delhi's wettest months, with about 189 mm and 198 mm of rain, and about 9 rainy days each. September still brings about 117 mm.
In 2026 the monsoon reached Delhi on 2 July, five days after the normal date of 27 June, according to Down To Earth. The weeks before it were described as hot and humid.
From our own work: the monsoon adds humidity to the heat, so the air feels heavy even when the rain stops. Rain can interrupt walking tours and outdoor monuments. Delhi is still visitable in these months, but plan for covered stops and a flexible day.
Late October to November: smog
Smog is the problem most "best time" pages leave out. Two examples from news reports:
- November 2021: Delhi had no "good", "satisfactory" or "moderate" air quality days. Its 30-day average Air Quality Index (AQI) was 376, with 11 "severe" days, the most for any November since 2015, according to Central Pollution Control Board data reported by Business Today.
- 7 November 2025: the average AQI at 7 am was 312, "very poor", with most areas between 300 and 400, reported by IANS.
Both reports name stubble burning in neighbouring states as a major cause. The 2021 report also names Diwali firecrackers and weather that traps pollution close to the ground.
These are two examples, not a forecast. Air quality changes daily, so check a live AQI reading before you travel and on the day.
We have not written a first-hand account of smog here, and it is not from our guiding notes. It comes only from the reports above.
December and January: fog and cold
The IMD's long-term figures record fog on about 15 days in December and about 21 days in January at the Palam station. Average lows fall to about 9°C in December and 7°C in January.
Fog affects travel more than sightseeing. On 29 December 2025, for example, 128 flights were cancelled at Delhi airport and visibility dropped to about 125 metres, reported by The News Minute.
From our own work: early mornings are foggy in winter, which can change plans, and winter is also a busy season at the monuments. Allow slack in your schedule, especially if you have a flight or train to catch the same day.
Why "best time to visit Delhi" pages leave you unsure
We read the best-time pages that rank for this question. The popular ones pick a favourite month, then mix in tour listings. One example, a GetYourGuide guide picks February and calls October to March the best window. The same page also:
- says February highs reach 80 to 90°F, while its own table gives 63°F for February;
- tells readers to avoid April to August, yet calls April to June the cheapest time;
- gives monsoon as "late June to mid-September" in one place and "July to September" in another;
- lists no sources for its weather figures and says nothing about air quality.
A "best month" tells you what to do. It does not tell you what can go wrong. This page works the other way round: it shows what goes wrong in each month, so you can decide for yourself.
If you have to come in a bad month
Sometimes the dates are fixed. A few things make a hard month easier:
- Summer (April to June): start at sunrise, keep to one main sight a day, rest indoors from late morning, and drink water often. In our experience, the hours from about 10 am to 12 noon are the hardest.
- Monsoon (July to September): pick covered or indoor stops and keep the day flexible for rain.
- Smog (November): check a live AQI reading before you go and on the day, and have an indoor plan ready.
- Fog (December and January): do not plan a tight connection on the same morning, and leave extra time for flights and trains.
And if your dates are flexible, February and March are the months with the fewest problems in the table above.
We would rather you came at the right time than came at all costs. A guide who knows Delhi can help you adjust the day, but no guide can change the weather.
Frequently asked questions
What is the worst time to visit Delhi?
May and June, when average daytime highs are about 41°C and 40°C according to the IMD. April, July, August and November are also difficult, for heat, rain and humidity, and smog.
What is the worst month for air pollution in Delhi?
November has been the worst in the reports we read. In November 2021 the average AQI was 376, and on 7 November 2025 it was 312 at 7 am. Check a live reading before you go.
Is Delhi too hot to visit in summer?
It is hard, not impossible. We have seen guests struggle between about 10 am and 12 noon, with red skin, tiredness and nosebleeds. If you come, go out at sunrise and rest in the afternoon.
Is it a bad idea to visit Delhi during the monsoon?
Not a bad idea, but a harder one. July and August bring the most rain and humidity, so expect interrupted outdoor plans.
Does fog affect travel to Delhi?
Yes. Fog is most common in December and January and can cancel flights and delay trains. On 29 December 2025, 128 flights were cancelled at Delhi airport.
What is the best time to visit Delhi, then?
In our view, winter and early spring are the easiest months, and February and March have the fewest problems in the table above. Check the forecast and air quality before you book.
Can I visit Delhi in summer with children or older relatives?
We would avoid it. The heat is the hardest part of Delhi for most guests, and children and older travellers have the least margin.
Sources
- India Meteorological Department: New Delhi (Palam) climatological normals, 1991 to 2020
- Down To Earth: Delhi welcomes monsoon 2026 (2 July 2026)
- Business Today: Delhi didn't record a single good air quality day in November 2021
- IANS: Delhi's air quality dips to very poor, 7 November 2025
- The News Minute: Dense fog leads to 128 flight cancellations at Delhi airport (29 December 2025)
- GetYourGuide: best time to visit New Delhi
