Biak in Summer
In summer (December, January and February), Biak sees average daytime highs around 28°C and overnight lows near 26°C, with 673 mm of rain over about 80 wet days across the season. It is the 2nd-warmest season and the 3rd-wettest season.
Across summer, daytime highs hold fairly steady around 28°C. The sky is clear or mostly clear about 4% of the time across summer, and the air most often feels miserable.
Summer is Biak's 3rd-best season to visit on our travel score. Biak 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 Biak's year-round climate.
- Avg daytime high
- 28°C
- 2nd-warmest season
- Avg overnight low
- 26°C
- Rainfall
- 673 mm
- 80 wet days
- Avg wind
- 11 km/h
- Travel score
- 3.6
- 3rd-best season
- Months
- Dec · Jan · Feb
Temperature in Biak in Summer
Across summer, daytime highs hold fairly steady around 28°C.
A typical summer day in Biak reaches about 28°C and drops to 26°C overnight. The warmest of the three months is December, the coolest January.
How summer really feels in Biak
Once humidity and wind are folded in, summer brings about 43 days that feel above 32°C and 0 that feel at or below 0°C.
The story in summer is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Biak 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° / 26° | 229 | 27.5 | 12.1 | 3.6 |
| Feb | 28° / 26° | 194 | 23.4 | 12 | 3.8 |
| Mar | 28° / 26° | 238 | 27.8 | 12 | 3.6 |
| Apr | 28° / 26° | 253 | 27.3 | 12 | 3.5 |
| May | 28° / 26° | 223 | 26.9 | 11.9 | 3.6 |
| Jun | 28° / 26° | 276 | 26.7 | 11.9 | 3.8 |
| Jul | 28° / 26° | 249 | 26.1 | 11.9 | 4.0 |
| Aug | 28° / 26° | 225 | 24.1 | 12 | 4.3 |
| Sep | 28° / 26° | 203 | 24.5 | 12 | 4.1 |
| Oct | 28° / 26° | 196 | 25.6 | 12 | 3.8 |
| Nov | 28° / 26° | 211 | 26.1 | 12.1 | 3.5 |
| Dec | 28° / 26° | 250 | 28.7 | 12.1 | 3.3 |
Cloud cover in Summer
The sky is clear or mostly clear about 4% of the time across summer.
Chance of precipitation in Summer
Biak gets around 673 mm of rain over 80 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels miserable — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 11 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 12 h 06 min in early December to 12 hours 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 5.1 kWh/m².
Is summer a good time to visit Biak?
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 Biak.
What to pack for Biak in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Biak sees daytime highs around 28°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 80 days see rain.
Sea temperature near Biak 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 offshore is warmest in November at about 30°C and coldest in March near 29°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 | 30 | 30 | 29 | 29 | 29 | 30 | 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 | 29 | Tropical |
| May | 30 | Tropical |
| Jun | 30 | Tropical |
| Jul | 29 | Tropical |
| Aug | 29 | Tropical |
| Sep | 29 | Tropical |
| Oct | 30 | Tropical |
| Nov | 30 | Tropical |
| Dec | 30 | Tropical |
UV index in Biak in Summer
Clear-sky midday UV across summer averages around 14 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Biak peaks around March 17 at about 16 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 18 at about 12 (extreme).
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) | 15 | 15 | 16 | 15 | 12 | 12 | 12 | 13 | 13 | 14 | 13 | 13 |
| Level | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 15 | Extreme |
| Feb | 15 | Extreme |
| Mar | 16 | Extreme |
| Apr | 15 | Extreme |
| May | 12 | Extreme |
| Jun | 12 | Extreme |
| Jul | 12 | Extreme |
| Aug | 13 | Extreme |
| Sep | 13 | Extreme |
| Oct | 14 | Extreme |
| Nov | 13 | Extreme |
| Dec | 13 | Extreme |
Where is Biak?
Biak sits at 1.2°S, 136.1°E, 10 m above sea level, in Indonesia. The nearest listed city is Ransiki, 216 km away.
Topography around Biak
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Biak.
Within 3 km, the terrain around Biak has only modest variations in elevation — a maximum elevation change of 169 m around an average of 23 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 219 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,442 m.
The land around Biak is covered by water (31%), trees (30%) and grassland (22%) within 3 km, water (52%) and trees (45%) within 16 km, and water (79%) and trees (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 Biak (-1.1767°, 136.082°, elevation 10 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.