Batu in Summer
In summer (December, January and February), Batu sees average daytime highs around 27°C and overnight lows near 20°C, with 1439 mm of rain over about 86 wet days across the season. It is the coldest season of the year and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 27°C. The sky is clear or mostly clear about 0% of the time across summer, and the air most often feels muggy.
Summer is Batu's weakest season of the year to visit on our travel score. For the whole year in context, see Batu's year-round climate.
- Avg daytime high
- 27°C
- coldest season of the year
- Avg overnight low
- 20°C
- Rainfall
- 1439 mm
- 86 wet days
- Avg wind
- 4 km/h
- Travel score
- 3.4
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Batu in Summer
Across summer, daytime highs hold fairly steady around 27°C.
A typical summer day in Batu reaches about 27°C and drops to 20°C overnight. The warmest of the three months is December, the coolest January.
Batu weather by month
How the three summer months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 27° / 20° | 510 | 29.7 | 12.4 | 3.4 |
| Feb | 26° / 20° | 493 | 27.6 | 12.3 | 3.3 |
| Mar | 27° / 20° | 464 | 28.9 | 12.1 | 3.5 |
| Apr | 27° / 20° | 295 | 25.5 | 11.8 | 3.9 |
| May | 27° / 19° | 138 | 18.5 | 11.6 | 5.1 |
| Jun | 27° / 18° | 72 | 12.8 | 11.6 | 6.0 |
| Jul | 26° / 17° | 51 | 9.8 | 11.6 | 6.5 |
| Aug | 27° / 17° | 37 | 7.4 | 11.7 | 6.7 |
| Sep | 28° / 18° | 57 | 8.1 | 12 | 6.5 |
| Oct | 28° / 19° | 152 | 15.4 | 12.2 | 5.4 |
| Nov | 27° / 20° | 326 | 23.3 | 12.4 | 4.1 |
| Dec | 27° / 20° | 436 | 28.4 | 12.4 | 3.6 |
Cloud cover in Summer
The sky is clear or mostly clear about 0% of the time across summer.
Chance of precipitation in Summer
Batu gets around 1439 mm of rain over 86 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 4 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 12 h 24 min in early December to 12 h 12 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 4.4 kWh/m².
Hazard calendar for Batu
In summer, Batu overlaps its cyclone and monsoon season. The full year is below, with each hazard's peak months called out.
Batu sits in the South Indian Ocean cyclone belt; the season peaks January–March.
Batu's monsoon runs November–April, when most of the year's rain falls.
Is summer a good time to visit Batu?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a weaker month for outdoor sightseeing in Batu.
What to pack for Batu in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Batu sees daytime highs around 27°C and nights near 20°C. Pack rain gear. Worth having: light clothes. About 86 days see rain.
Sea temperature near Batu in Summer
The nearest coast averages about 29°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 47 km away) is warmest in November at about 30°C and coldest in August near 28°C.
The water stays above 20°C all year — warm enough for a swim any month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 29 | 29 | 29 | 30 | 30 | 29 | 28 | 28 | 28 | 29 | 30 | 30 |
| Comfort | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 29 | Tropical |
| Feb | 29 | Tropical |
| Mar | 29 | Tropical |
| Apr | 30 | Tropical |
| May | 30 | Tropical |
| Jun | 29 | Tropical |
| Jul | 28 | Tropical |
| Aug | 28 | Tropical |
| Sep | 28 | Tropical |
| Oct | 29 | Tropical |
| Nov | 30 | Tropical |
| Dec | 30 | Tropical |
UV index in Batu in Summer
Clear-sky midday UV across summer averages around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Batu peaks around March 17 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 16 at about 8 (very high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 14 | 13 | 15 | 13 | 10 | 8 | 10 | 12 | 13 | 13 | 10 | 12 |
| Level | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | Very high | Extreme | Extreme | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 14 | Extreme |
| Feb | 13 | Extreme |
| Mar | 15 | Extreme |
| Apr | 13 | Extreme |
| May | 10 | Extreme |
| Jun | 8 | Very high |
| Jul | 10 | Very high |
| Aug | 12 | Extreme |
| Sep | 13 | Extreme |
| Oct | 13 | Extreme |
| Nov | 10 | Extreme |
| Dec | 12 | Extreme |
Air quality in Batu in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Batu is worst in May — around 101 µg/m³ PM2.5 (unhealthy), and holds fairly steady the rest of the year.
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 76 | 71 | 87 | 99 | 101 | 95 | 81 | 66 | 69 | 80 | 87 | 81 |
| Level | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 76 | Unhealthy |
| Feb | 71 | Unhealthy |
| Mar | 87 | Unhealthy |
| Apr | 99 | Unhealthy |
| May | 101 | Unhealthy |
| Jun | 95 | Unhealthy |
| Jul | 81 | Unhealthy |
| Aug | 66 | Unhealthy |
| Sep | 69 | Unhealthy |
| Oct | 80 | Unhealthy |
| Nov | 87 | Unhealthy |
| Dec | 81 | Unhealthy |
Where is Batu?
Batu sits at 7.9°S, 112.5°E, 881 m above sea level, in Indonesia. The nearest listed city is Singosari, 15 km away.
Topography around Batu
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Batu.
Within 3 km, the terrain around Batu has significant variations in elevation — a maximum elevation change of 588 m around an average of 915 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 2,889 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,645 m.
The land around Batu is covered by trees (45%) and artificial surfaces (40%) within 3 km, trees (75%) within 16 km, and trees (49%) and cropland (21%) within 80 km.
Indonesia travel facts
- Travel advisory
- Level 2
- Exercise Increased Caution
- Power plugs
- Type C / F
- 230 V · 50 Hz
- Prices
- ≈ 29% of US
- price level, 2025
- GDP per capita
- $5,060
- 2025
- Happiness
- 5.6 / 10
- World Happiness, 2025
- Safe drinking water
- 30%
- of population, 2024
- Homicide rate
- 0.3
- per 100k, 2022
- Road deaths
- 11.3
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Low
- EF EPI 471
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Batu (-7.87°, 112.5283°, elevation 881 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.