Chennai (Madras) weather in July
July in Chennai: sweltering, rainy — not the time — 40°C afternoons.
Updated September 2026 · climate normals from ERA5 reanalysis
#9 of 12 months in Chennai · #1219 of 1413 destinations to visit in July · comfort 49/100 (tier F)
- Days
- 36°C
- Nights
- 26°C
- Wet days
- 17
- Sun
- 8 h
- Humidity
- 69%
- Daylight
- 13 h

Traveller notes on Chennai in July
Other months in Chennai
Regulars are specific about timing within the month: the northeast monsoon generally sets in around the 20th and intensifies toward month's end, so early October can stay relatively dry while the back third turns genuinely wet, arriving in spells of three to four days followed by roughly a week of calm rather than continuous rain. Our row backs the wet second-half reality, a striking 167.8mm of rain across 18.9 days, alongside intense heat, 33.6C reading as a severe 39C at 80 percent humidity, over 24.9C nights. Regulars call the mornings and evenings genuinely pleasant from here through February, a real improvement over the pre-monsoon months even with the rain risk factored in. The sea holds a warm 30C. The record: 9.2 hours of sun, a 15.1 kph wind and AQI 80.
Regulars call September the better half of a two-month stretch, more pleasant than August though still hot and humid, with the southwest monsoon rain arriving as sporadic few-minute showers rather than the continuous rain of a proper wet month. Our row backs the transitional read - 34.7C reading as a real 40C at 75.5 percent humidity, with 104.5mm across 16.6 days - frequent but each fall brief. The month that actually soaks this coast has not started yet: the northeast monsoon, which brings most of Tamil Nadu's annual rain, sets in around the 20th of October and intensifies from there. The sea is 29.5C. The record: 8.8 hours of sun, a 17.2 kph wind and AQI 66.
The north-east monsoon runs from about the 20th of October to the middle of December here, and regulars describe its rhythm rather than its total: two or three days of rain followed by a week or more of nothing. That is how to read our 150.9mm falling across 10.3 days. Opinion splits accordingly - some call December blissful and the best month of the Chennai year, cool by local standards; others report solid rain and suggest January instead. Both are describing the same month from different weeks of it. Heat is moderate for here at 30.3C reading as 33C. The record: 22.3C nights, 9.1 hours of sun, a 27.3C sea and AQI 73.
March is the last month of the Tamil Nadu season and it does not last the whole month. Regulars put the good window at November to March and then qualify it: mid to late March is mostly sunny with highs in the mid to high 30s and lows in the mid 20s, and it starts getting hotter after the middle of the month. Our row's 34.7C average high reads as 39C once the coastal humidity is counted, at 74 percent. Their warning about what follows is blunt - April, May and June are hot and humid enough that people describe struggling to leave the room or the car - and the alternative they recommend for comfort is late November or December. The record: 24C nights, 1.6 precipitation days carrying 7.2mm, 11 hours of sun and a 28.8C sea.
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Chennai climate normals — July
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Chennai in July
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Shoulder seasonschool holidays in 5 of the markets that fill it, an ordinary month(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Chennai's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherChennai's weather peaks January–March, best around February.
Best weatherFair weatherToughest weather
What's on in Chennai in July
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Festival
Aadi month at Amman temples
17 Jul – 16 Aug · usuallyReligious feastThrough the Tamil month of Aadi, goddess temples across the city hold Friday festivals and neighbourhoods cook and hand out koozh, a millet porridge offering. Aadi is thought unlucky for weddings, so the wedding halls go quiet. Source ↗
Nearby, and something's on
Within 300 km of Chennai — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Chennai?
Chennai in July — FAQ
- Is July a good time to visit Chennai?
- July in Chennai: sweltering, rainy — not the time — 40°C afternoons. It ranks #9 of 12 months for Chennai on SeasonMap's comfort score (49/100).
- What is the weather like in Chennai in July?
- In July, Chennai averages a daily high of 35.9°C and a low of 26.1°C, with about 109.2 mm of rain over roughly 16.6 rainy days.
- What is the air quality in Chennai in July?
- Chennai has a mean US Air Quality Index of about 54 in July.
Within 300 km: Pondicherry's Bastille Day on 14 Jul, and Mysuru's Ashada Fridays on Chamundi Hill around 5 Jul – 15 Aug.