South Delhi’s weather runs through three distinct chapters every year — a genuinely hot summer, a monsoon that brings real relief and real flooding risk in equal measure, and a mild but often fog-bound winter. If you’re planning a move, here’s what to actually expect month to month, plus the one factor that matters here more than almost anywhere else in India: air quality.
Key Takeaways
- South Delhi has a humid subtropical climate, with summer highs near 38°C (peaking above 45°C in heatwaves) and winter lows around 3–7°C with dense fog.
- The monsoon runs late June through mid-September, delivering most of Delhi’s roughly 750mm annual rainfall.
- AQI, not just temperature, drives daily planning here — even during the cleaner monsoon season, Delhi’s air quality index regularly sits in the “unhealthy” range.
South Delhi’s Three Seasons
Summer (April–June)
Temperatures climb steadily from early April, peaking in late May or early June with average highs near 38°C — and occasional heatwaves pushing past 45°C on the worst days. Evenings offer little relief until the first pre-monsoon thunderstorms, locally called andhi, arrive.
Monsoon (Late June–Mid-September)
The southwest monsoon brings the bulk of Delhi’s roughly 750mm annual rainfall, along with high humidity and occasional waterlogging in low-lying pockets. Temperatures ease slightly, though the mugginess can feel just as draining as summer’s dry heat.
Winter (November–February)
Winter is genuinely mild by day but can turn sharply cold at night, with January lows dropping to around 3–7°C. Dense fog is the defining feature of a South Delhi winter morning, frequently delaying flights and slowing road traffic.
Why AQI Matters as Much as Temperature
This is the factor that genuinely sets Delhi apart. Even during the monsoon, when rainfall temporarily washes pollutants out of the air, Delhi’s Air Quality Index regularly still sits in the “unhealthy” range for sensitive groups. Winter is far worse: calm winds, temperature inversions, fog, and seasonal stubble burning combine to trap pollutants near the ground for weeks at a time. Anyone moving to South Delhi, especially with children, elderly family members, or respiratory conditions, should treat AQI monitoring as a daily habit alongside checking the weather.
Best Time to Move or Visit
October through March offers the most comfortable temperatures for house-hunting, moving, and settling in, though be prepared for fog-related morning delays in December and January. If air quality is a major concern, spring (March–April) offers a reasonable middle ground — mild temperatures with typically better air than peak winter.
Conclusion
South Delhi’s weather is genuinely livable most of the year, but it rewards planning around two things at once: the season, and the air. Check both before you commit to a move-in date, and budget for indoor air purifiers if you’re settling in ahead of winter.
Frequently Asked Questions
What type of climate does South Delhi have?
A humid subtropical climate, with very hot summers, a monsoon season from late June to mid-September, and mild winters marked by dense fog.
What is the hottest month in South Delhi?
May is typically the hottest month, with average highs near 38 degrees Celsius and occasional heatwaves pushing past 45 degrees.
What is the coldest month in South Delhi?
January is coldest, with lows that can drop to around 3 to 7 degrees Celsius and frequent morning fog.
Why does AQI matter as much as temperature in South Delhi?
Delhi’s air quality worsens significantly in winter due to calm winds, fog, and stubble burning, making AQI a bigger factor in daily planning than in most Indian cities.
When is the best time to move to or visit South Delhi?
October to March offers the most comfortable temperatures for house-hunting and settling in, though winter mornings can bring fog-related delays.
Planning your move around the seasons? Browse current flats for rent across South Delhi to line up viewings before the weather turns.
Written by the South Delhi Rentwala Editorial Team, which helps newcomers plan their move around South Delhi’s real seasonal patterns. Learn more about us.
Published Jan 28, 2026 · Last Updated July 9, 2026 · 5 min read