Boyolali in Summer
In summer (December, January and February), Boyolali sees average daytime highs around 28°C and overnight lows near 21°C, with 1285 mm of rain over about 85 wet days across the season. It is the 3rd-warmest season and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 28°C. The sky is clear or mostly clear about 1% of the time across summer, and the air most often feels oppressive.
Summer is Boyolali's weakest season of the year to visit on our travel score. Boyolali has little temperature swing across the year, so its calendar seasons blur — the season framing matters less here than for a place with four distinct seasons. For the whole year in context, see Boyolali's year-round climate.
- Avg daytime high
- 28°C
- 3rd-warmest season
- Avg overnight low
- 21°C
- Rainfall
- 1285 mm
- 85 wet days
- Avg wind
- 4 km/h
- Travel score
- 3.2
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Boyolali in Summer
Across summer, daytime highs hold fairly steady around 28°C.
A typical summer day in Boyolali reaches about 28°C and drops to 21°C overnight. The warmest of the three months is February, the coolest January.
Boyolali 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 | 28° / 21° | 447 | 29.2 | 12.4 | 3.2 |
| Feb | 28° / 21° | 451 | 27.4 | 12.2 | 3.0 |
| Mar | 29° / 21° | 407 | 29.3 | 12.1 | 3.0 |
| Apr | 29° / 21° | 282 | 26.7 | 11.8 | 3.3 |
| May | 29° / 21° | 148 | 20.4 | 11.7 | 4.3 |
| Jun | 28° / 20° | 96 | 14.7 | 11.6 | 5.3 |
| Jul | 28° / 19° | 62 | 10.4 | 11.6 | 6.3 |
| Aug | 28° / 19° | 42 | 6.8 | 11.8 | 6.8 |
| Sep | 28° / 20° | 71 | 9.6 | 12 | 5.7 |
| Oct | 29° / 21° | 179 | 19.7 | 12.2 | 4.3 |
| Nov | 29° / 21° | 340 | 26.9 | 12.3 | 3.3 |
| Dec | 28° / 21° | 387 | 27.9 | 12.4 | 3.3 |
Cloud cover in Summer
The sky is clear or mostly clear about 1% of the time across summer.
Chance of precipitation in Summer
Boyolali gets around 1285 mm of rain over 85 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels oppressive — 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 4.5 kWh/m².
Hazard calendar for Boyolali
In summer, Boyolali overlaps its cyclone and rainy season season. The full year is below, with each hazard's peak months called out.
Boyolali sits in the South Indian Ocean cyclone belt; the season peaks January–March.
Boyolali's rainy season runs November–April, when most of the year's rain falls.
Is summer a good time to visit Boyolali?
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 Boyolali.
What to pack for Boyolali in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Boyolali sees daytime highs around 28°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 85 days see rain.
Sea temperature near Boyolali 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 64 km away) is warmest in March at about 29°C and coldest in August near 25°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 | 29 | 29 | 28 | 26 | 25 | 25 | 26 | 28 | 29 |
| Comfort | Tropical | Tropical | Tropical | Tropical | Tropical | Warm | Warm | Warm | Warm | Warm | Warm | Tropical |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 29 | Tropical |
| Feb | 29 | Tropical |
| Mar | 29 | Tropical |
| Apr | 29 | Tropical |
| May | 29 | Tropical |
| Jun | 28 | Warm |
| Jul | 26 | Warm |
| Aug | 25 | Warm |
| Sep | 25 | Warm |
| Oct | 26 | Warm |
| Nov | 28 | Warm |
| Dec | 29 | Tropical |
UV index in Boyolali 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 Boyolali peaks around March 14 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 14 at about 6 (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 | 14 | 15 | 12 | 8 | 6 | 10 | 11 | 13 | 13 | 9 | 11 |
| Level | Extreme | Extreme | Extreme | Extreme | Very high | High | Very high | Extreme | Extreme | Extreme | Very high | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 14 | Extreme |
| Feb | 14 | Extreme |
| Mar | 15 | Extreme |
| Apr | 12 | Extreme |
| May | 8 | Very high |
| Jun | 6 | High |
| Jul | 10 | Very high |
| Aug | 11 | Extreme |
| Sep | 13 | Extreme |
| Oct | 13 | Extreme |
| Nov | 9 | Very high |
| Dec | 11 | Extreme |
Air quality in Boyolali 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 Boyolali is worst in April — around 58 µg/m³ PM2.5 (unhealthy), about 1.7× the cleanest month (September, 34 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 48 | 46 | 54 | 58 | 57 | 51 | 42 | 35 | 34 | 37 | 42 | 42 |
| Level | Poor | Poor | Poor | Unhealthy | Unhealthy | Poor | Poor | Moderate | Moderate | Poor | Poor | Poor |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 48 | Poor |
| Feb | 46 | Poor |
| Mar | 54 | Poor |
| Apr | 58 | Unhealthy |
| May | 57 | Unhealthy |
| Jun | 51 | Poor |
| Jul | 42 | Poor |
| Aug | 35 | Moderate |
| Sep | 34 | Moderate |
| Oct | 37 | Poor |
| Nov | 42 | Poor |
| Dec | 42 | Poor |
Where is Boyolali?
Boyolali sits at 7.5°S, 110.6°E, 438 m above sea level, in Indonesia. The nearest listed city is Karanganom, 13 km away.
Topography around Boyolali
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Boyolali.
Within 3 km, the terrain around Boyolali has significant variations in elevation — a maximum elevation change of 260 m around an average of 440 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 2,558 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,291 m.
The land around Boyolali is covered by trees (64%) and artificial surfaces (31%) within 3 km, trees (67%) within 16 km, and trees (61%) 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 Boyolali (-7.5331°, 110.5958°, elevation 438 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.