Dumai weather in August

In August, Dumai sees average daytime highs of 32°C and overnight lows near 24°C, with 195 mm of rain across 24 wet days and about 12.1 hours of daylight. It is the 6th-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 32°C through the month. The sky is clear or mostly clear about 3% of the time in August, and the air most often feels miserable.

Daylight stretches from about 12 h 06 min at the start of August to 12 hours by month's end. Set against the rest of the year, August is Dumai's 5th-clearest and 6th-windiest month. For the whole year in context, see Dumai's year-round climate.

Daytime high
32°
6th warmest
Overnight low
24°
3rd coldest
Rainfall
195 mm
24 wet days
Daylight
12 h 06 min
6:17 AM – 6:20 PM
Cloud cover
82%
5th clearest
Wind
5 km/h
6th windiest
Solar energy
5.13 kWh/m²
Travel score
2.7
out of 10

Dumai is city in Riau Province, Indonesia.

Density
202/km²
people per km²
Founded
1999

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 32°C through the month.

A typical August day in Dumai reaches about 32°C in the afternoon and slips back to 24°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 30°C and 33°C. Set against its neighbours, August runs on par with July and on par with September.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13224
23224
33224
43224
53224
63224
73224
83224
93224
103224
113224
123224
133224
143224
153224
163224
173224
183224
193224
203224
213224
223224
233224
243224
253224
263224
273224
283224
293224
303224
313224

How August really feels in Dumai

Once humidity and wind are folded in, August averages 31 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
31
31 feel dangerously hot (≥ 39°C)
Days feeling ≤ C
0
wind chill below the day's low

The story in August is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Dumai weather by month

How August compares with the rest of the year at a glance. August is the 6th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 24°20121.311.93.3
Feb32° / 25°12316.811.93.2
Mar32° / 25°21725.1122.5
Apr32° / 25°24927.6122.2
May32° / 25°22426.312.12.3
Jun32° / 25°15621.312.12.7
Jul32° / 24°16220.412.13.0
Aug32° / 24°1952412.12.7
Sep32° / 24°25326.1122.5
Oct31° / 24°30828.2122.4
Nov31° / 24°38728.511.92.4
Dec31° / 24°34327.711.92.7

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 3% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 10% of August, with mostly cloudy or overcast conditions the remaining 87%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
11981
21882
31783
41783
51684
61684
71684
81486
91486
101486
111486
121387
131387
141387
151387
161387
171387
181288
191288
201288
211189
221189
231189
241090
251090
261090
271090
281090
291090
301090
311090

Chance of precipitation in August

Any precipitation

Dumai gets around 195 mm of rain over 24 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 78% and peaks near 83% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%151015202531
Rain chance (%)
167
267
368
469
570
671
772
873
974
1075
1177
1278
1379
1480
1580
1681
1781
1882
1982
2082
2182
2282
2382
2482
2582
2682
2782
2882
2982
3083
3183

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

Most of August feels miserable — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, August lands in the miserable band about 89% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Oppressive (%)Miserable (%)
11387
21387
31387
41387
51288
61288
71288
81288
91189
101189
111189
121189
131189
141189
151189
161189
171189
181189
191189
201189
211189
221189
231189
241189
251189
261189
271189
281189
291189
301189
311189

Wind in August

Winds average 5 km/h in August.

Across August, daily wind ranges from about 5 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 12 h 06 min at the start of August to 12 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over August. Sunrise moves from 6:18 AM to 6:13 AM, and sunset from 6:22 PM to 6:15 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.16:186:22
212.16:186:22
312.16:186:22
412.16:186:22
512.16:186:22
612.16:186:22
712.16:186:22
812.16:186:22
912.16:186:21
1012.16:186:21
1112.16:176:21
1212.16:176:21
1312.16:176:21
1412.16:176:20
1512.16:176:20
1612.16:176:20
1712.16:176:20
1812.16:166:19
1912.16:166:19
2012.06:166:19
2112.06:166:19
2212.06:166:18
2312.06:156:18
2412.06:156:18
2512.06:156:17
2612.06:156:17
2712.06:146:17
2812.06:146:16
2912.06:146:16
3012.06:146:16
3112.06:136:15

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.13 kWh/m².

For context, solar energy here swings from a low near 4.21 kWh/m² to a high of 5.49 kWh/m² in February across the year — August's 5.13 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.2Bright
25.2Bright
35.2Bright
45.2Bright
55.2Bright
65.2Bright
75.2Bright
85.2Bright
95.2Bright
105.2Bright
115.2Bright
125.2Bright
135.2Bright
145.2Bright
155.1Bright
165.1Bright
175.1Bright
185.1Bright
195.1Bright
205.1Bright
215.1Bright
225.1Bright
235.1Bright
245.1Bright
255.1Bright
265.1Bright
275.1Bright
285.1Bright
295.1Bright
305.1Bright
315.1Bright
Planning a trip in August

Is August a good time to visit Dumai?

Our two travel scores rate August for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

2.7
Sightseeing
4th-best month of the year
4.2
Beach & pool
5th-best month of the year

August is a weaker month for outdoor sightseeing in Dumai.

What to pack for Dumai in August

From August's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In August, Dumai sees daytime highs around 32°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 24 days see rain.

light clothesrain gearsun protection

Sea temperature near Dumai in August

The nearest coast averages about 30°C in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 48 km away) is warmest in May at about 30°C and coldest in January near 29°C.

The water stays above 20°C all year — warm enough for a swim any month.

28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr30Tropical
May30Tropical
Jun30Tropical
Jul30Tropical
Aug30Tropical
Sep30Tropical
Oct30Tropical
Nov29Tropical
Dec29Tropical

UV index in Dumai in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Dumai peaks around February 17 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 20 at about 10 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeFeb 17UV 14Jun 20UV 10
UV index (midday)Level
Jan13Extreme
Feb14Extreme
Mar13Extreme
Apr13Extreme
May12Extreme
Jun10Very high
Jul10Extreme
Aug12Extreme
Sep13Extreme
Oct14Extreme
Nov11Extreme
Dec11Extreme

Air quality in Dumai in August

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where August falls, not just the annual average.

Air quality in Dumai is worst in September — around 43 µg/m³ PM2.5 (poor), about 2.9× the cleanest month (December, 15 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateSep 943 µg/m³Dec 1015 µg/m³
PM2.5 (µg/m³)Level
Jan18Moderate
Feb31Moderate
Mar36Poor
Apr26Moderate
May20Moderate
Jun21Moderate
Jul37Poor
Aug42Poor
Sep43Poor
Oct30Moderate
Nov15Moderate
Dec15Moderate
Location & terrain

Where is Dumai?

Dumai sits at 1.7°N, 101.4°E, 7 m above sea level, in Indonesia. The nearest listed city is Balai Pungut, 70 km away.

Topography around Dumai

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Dumai.

Within 3 km, the terrain around Dumai has only modest variations in elevation — a maximum elevation change of 27 m around an average of 5 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 53 m; within 80 km, only modest variations in elevation — a maximum elevation change of 77 m.

The land around Dumai is covered by artificial surfaces (51%) and trees (31%) within 3 km, trees (66%) and water (20%) within 16 km, and trees (64%) and water (29%) within 80 km.

3 km
27 m
16 km
53 m
80 km
77 m
treesshrubsgrasslandartificial surfacesbare terrainwatermangroves
August weather nearby: Balai Pungut 70 km · Kampung Teluk Kemang 100 km · Sungai Udang 103 km · Port Dickson 103 km · Klebang Besar 104 km · Bukit Rambai 105 km · Malacca 106 km · Kampong Masjid Tanah 107 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
Muslim 87%Protestant 8%Roman Catholic 3%Hindu 2%

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 Dumai (1.6671°, 101.4432°, elevation 7 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).