Chennai weather in October
In October, Chennai has daytime highs averaging 31 °C, nights around 25 °C, with 19 wet days, and a sea temperature of 29 °C. Figures are 1991–2020 climate normals.
- 30.6°C Average high
- 24.5°C Average low
- 19days Wet days
- 215mm Rainfall
- 29.3°C Sea temperature
- 12h Daylight
Daily temperatures through October
How October develops
Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.
| Days | Avg high | Avg low | Chance of rain |
|---|---|---|---|
| 1–10 October | 31.5 °C | 25.1 °C | 58 % |
| 11–20 October | 30.8 °C | 24.7 °C | 60 % |
| 21–31 October | 29.5 °C | 24.0 °C | 68 % |
- Average highs fall from 31.5 °C early in October to 29.5 °C by the end of it.
- Rain is most likely over days 21–31 of October (68 % of days) and least likely over days 1–10 (58 %).
What to expect
| Measure | Typical October | Share of the month |
|---|---|---|
| Days above 25 °C | 31 of 31 | 99 % |
| Days above 30 °C | 19 of 31 | 63 % |
| Days below 0 °C | 0 of 31 | 0 % |
| Days with more than 1 mm rain | 19 of 31 | 62 % |
Conditions in October
| Measure | Average |
|---|---|
| Mean temperature | 27 °C |
| Record high (1991–2020) | 36 °C |
| Record low (1991–2020) | 20 °C |
| Relative humidity | 81 % |
| Wind speed | 15 km/h |
| Cloud cover | 71 % |
October compared with the months around it
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| August | 33.3 °C | 98 mm | 86 % |
| September | 32.6 °C | 109 mm | 76 % |
| October | 30.6 °C | 215 mm | 71 % |
| November | 28.5 °C | 225 mm | 66 % |
| December | 27.4 °C | 116 mm | 58 % |
See all twelve months for Chennai
- October is the 8th warmest month here.
- It is the 11th driest month of the year.
- It ranks 8th for least cloud cover.
- Days last about 12 hours from sunrise to sunset.
- It rains on 19 of 31 days — 62 % of the month.
- Nights are about 6.0 °C cooler than the middle of the day.
- The hottest October day on record since 1991 reached 36 °C, 5.4 °C above the usual daytime high.
- Beach score: 64 / 100 — see how this is calculated.
Nearby destinations in October
| Destination | Avg high | Wet days | Sea |
|---|---|---|---|
| Chennai | 31 °C | 19 | 29 |
| Tiruvottiyūr | 31 °C | 18 | 29 |
| Avadi | 31 °C | 19 | 29 |
QuestionsOctober in Chennai, answered
How warm is Chennai in October?
Daily highs average 31 °C and nights fall to about 25 °C, a spread of 6.0 °C between afternoon and dawn. That makes October the 8th warmest month of the year here.
Does it rain much in Chennai in October?
October averages 215 mm of rain, spread over about 19 of the 31 days — 62 % of the month. Cloud cover averages 71 % of the sky.
Is the sea warm enough to swim in October?
The sea averages 29 °C off Chennai in October. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.
How long are the days in October?
Chennai averages 12 hours between sunrise and sunset in October. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.
Data sources and method
- ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
- Open-Meteo — Open-Meteo.com. CC BY 4.0
- NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
- GeoNames — GeoNames.org. CC BY 4.0
- Normal period
- 1991–2020
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.
Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.