Dumai weather in January
In January, Dumai has daytime highs averaging 29 °C, nights around 23 °C, with 21 wet days. Figures are 1991–2020 climate normals.
- 28.9°C Average high
- 23.3°C Average low
- 21days Wet days
- 208mm Rainfall
- 12h Daylight
Daily temperatures through January
How January 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 January | 28.8 °C | 23.3 °C | 72 % |
| 11–20 January | 28.9 °C | 23.3 °C | 67 % |
| 21–31 January | 29.0 °C | 23.3 °C | 67 % |
- Rain is most likely over days 1–10 of January (72 % of days) and least likely over days 21–31 (67 %).
What to expect
| Measure | Typical January | Share of the month |
|---|---|---|
| Days above 25 °C | 31 of 31 | 99 % |
| Days above 30 °C | 3.7 of 31 | 12 % |
| Days below 0 °C | 0 of 31 | 0 % |
| Days with more than 1 mm rain | 21 of 31 | 69 % |
Conditions in January
| Measure | Average |
|---|---|
| Mean temperature | 26 °C |
| Record high (1991–2020) | 33 °C |
| Record low (1991–2020) | 19 °C |
| Relative humidity | 87 % |
| Wind speed | 10 km/h |
| Cloud cover | 83 % |
January compared with the months around it
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| January | 28.9 °C | 208 mm | 83 % |
| February | 29.7 °C | 135 mm | 79 % |
| March | 30.2 °C | 226 mm | 81 % |
| November | 29.1 °C | 389 mm | 93 % |
| December | 28.7 °C | 345 mm | 91 % |
See all twelve months for Dumai
- January is the 11th warmest month here.
- It is the 5th driest month of the year.
- It ranks 6th for least cloud cover.
- Days last about 12 hours from sunrise to sunset.
- It rains on 21 of 31 days — 69 % of the month.
- Nights are about 5.6 °C cooler than the middle of the day.
- The hottest January day on record since 1991 reached 33 °C, 3.7 °C above the usual daytime high.
Nearby destinations in January
| Destination | Avg high | Wet days | Sea |
|---|---|---|---|
| Dumai | 29 °C | 21 | – |
| Malacca | 29 °C | 16 | 28 |
| Sepang | 29 °C | 19 | 29 |
| Pekanbaru | 29 °C | 24 | – |
| Seremban | 29 °C | 18 | – |
| Muar | 29 °C | 18 | 28 |
| Kajang | 30 °C | 20 | – |
QuestionsJanuary in Dumai, answered
How warm is Dumai in January?
Daily highs average 29 °C and nights fall to about 23 °C, a spread of 5.6 °C between afternoon and dawn. That makes January the 10th warmest month of the year here.
Does it rain much in Dumai in January?
January averages 208 mm of rain, spread over about 21 of the 31 days — 69 % of the month. Cloud cover averages 83 % of the sky.
How long are the days in January?
Dumai averages 12 hours between sunrise and sunset in January. 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.