Castanhal weather in August

In August, Castanhal sees average daytime highs of 32°C and overnight lows near 23°C, with 51 mm of rain across 13 wet days and about 12 hours of daylight. It is the 5th-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 38% of the time in August, and the air most often feels oppressive.

Daylight stretches from about 11 h 54 min at the start of August to 12 hours by month's end. Set against the rest of the year, August is Castanhal's 1st-clearest and 5th-windiest month. For the whole year in context, see Castanhal's year-round climate.

Daytime high
32°
5th warmest
Overnight low
23°
3rd coldest
Rainfall
51 mm
13 wet days
Daylight
12 hours
6:17 AM – 6:15 PM
Cloud cover
47%
1st clearest
Wind
9 km/h
5th windiest
Solar energy
5.69 kWh/m²
Travel score
3.6
out of 10

Castanhal is human settlement in Brazil.

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 Castanhal reaches about 32°C in the afternoon and slips back to 23°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 31°C and 34°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)
13222
23222
33223
43223
53223
63223
73223
83223
93223
103223
113223
123223
133223
143223
153223
163223
173223
183323
193323
203323
213323
223323
233323
243323
253323
263323
273323
283323
293323
303323
313323

How August really feels in Castanhal

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
heat index over the day's high
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.

Castanhal weather by month

How August compares with the rest of the year at a glance. August is the 5th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 23°26927.112.12.6
Feb30° / 23°35426.9122.5
Mar30° / 23°45630.5122.5
Apr30° / 23°42729.6122.5
May31° / 23°27827.711.92.7
Jun31° / 23°12021.411.93.1
Jul32° / 22°9118.111.93.5
Aug32° / 23°5113123.6
Sep33° / 23°348.8123.6
Oct34° / 23°348.1123.4
Nov33° / 24°498.812.13.3
Dec33° / 24°11817.412.13.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 38% of the time in August, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 43% of August, with mostly cloudy or overcast conditions the remaining 19%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
18218
28218
38218
48317
58317
68317
78317
88218
98119
108119
118020
128020
138020
148020
158020
168020
178020
188020
198020
208020
218020
228119
238119
248218
258218
268218
278218
288218
298218
308218
318218

Chance of precipitation in August

Any precipitation

Castanhal gets around 51 mm of rain over 13 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 42% and peaks near 48% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
148
247
347
446
546
645
745
844
944
1044
1144
1244
1343
1443
1543
1642
1742
1841
1941
2041
2140
2240
2340
2440
2539
2639
2738
2838
2938
3037
3137

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the oppressive band about 97% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
10982
20982
30982
40982
50982
60982
70973
80973
90973
100973
111963
121963
131963
141963
151963
161963
171963
181963
191963
201963
211963
221963
231963
241963
250973
260982
270982
280982
290982
300982
310982

Wind in August

Winds average 9 km/h in August.

Across August, daily wind ranges from about 8 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
189calm
199calm
209calm
219calm
229calm
239calm
249calm
259calm
269calm
279calm
289calm
299calm
309calm
319calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 11 h 54 min at the start of August to 12 hours by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 6 minutes over August. Sunrise moves from 6:19 AM to 6:13 AM, and sunset from 6:16 PM to 6:11 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.96:196:16
211.96:196:16
311.96:196:16
411.96:196:16
511.96:196:16
611.96:196:16
711.96:196:16
811.96:196:16
912.06:186:16
1012.06:186:15
1112.06:186:15
1212.06:186:15
1312.06:186:15
1412.06:186:15
1512.06:176:15
1612.06:176:15
1712.06:176:14
1812.06:176:14
1912.06:166:14
2012.06:166:14
2112.06:166:14
2212.06:156:13
2312.06:156:13
2412.06:156:13
2512.06:156:13
2612.06:146:12
2712.06:146:12
2812.06:146:12
2912.06:136:12
3012.06:136:11
3112.06:136:11

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.69 kWh/m².

For context, solar energy here swings from a low near 4.05 kWh/m² to a high of 6.13 kWh/m² in October across the year — August's 5.69 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.5Bright
65.5Bright
75.6Bright
85.6Bright
95.6Bright
105.6Bright
115.6Bright
125.6Bright
135.6Bright
145.7Bright
155.7Bright
165.7Bright
175.7Bright
185.7Bright
195.7Bright
205.8Bright
215.8Bright
225.8Bright
235.8Bright
245.8Bright
255.8Bright
265.8Bright
275.8Bright
285.8Bright
295.9Bright
305.9Bright
315.9Bright
Planning a trip in August

Hazard calendar for Castanhal

In seasonPeak

None of Castanhal's seasonal hazards are active in August. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Castanhal's monsoon runs January–May, when most of the year's rain falls.

Monsoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is August a good time to visit Castanhal?

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

3.6
Sightseeing
1st-best month of the year
6.1
Beach & pool
4th-best month of the year

August is a weaker month for outdoor sightseeing in Castanhal. The water and warmth also suit a beach or pool day.

What to pack for Castanhal in August

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

In August, Castanhal sees daytime highs around 32°C and nights near 23°C. Pack light clothes. Worth having: rain gear and sun protection. About 13 days see rain.

light clothesrain gearsun protection

Sea temperature near Castanhal in August

The nearest coast averages about 29°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 53 km away) is warmest in June at about 29°C and coldest in March near 28°C.

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

26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb28Tropical
Mar28Tropical
Apr29Tropical
May29Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec29Tropical

UV index in Castanhal in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Castanhal peaks around March 15 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 18 at about 10 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeMar 15UV 15Jul 18UV 10
UV index (midday)Level
Jan13Extreme
Feb14Extreme
Mar15Extreme
Apr14Extreme
May12Extreme
Jun11Extreme
Jul10Extreme
Aug10Extreme
Sep12Extreme
Oct12Extreme
Nov10Extreme
Dec11Extreme

Air quality in Castanhal 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 Castanhal is worst in November — around 26 µg/m³ PM2.5 (moderate), about 2.7× the cleanest month (June, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateNov 1725 µg/m³Jun 1610 µg/m³
PM2.5 (µg/m³)Level
Jan18Moderate
Feb21Moderate
Mar21Moderate
Apr17Moderate
May11Good
Jun10Good
Jul11Good
Aug13Moderate
Sep14Moderate
Oct17Moderate
Nov26Moderate
Dec20Moderate
Location & terrain

Where is Castanhal?

Castanhal sits at 1.3°S, 47.9°W, 46 m above sea level, in Brazil. The nearest listed city is Santa Isabel do Pará, 26 km away.

Topography around Castanhal

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

Within 3 km, the terrain around Castanhal has only modest variations in elevation — a maximum elevation change of 46 m around an average of 40 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 69 m; within 80 km, only modest variations in elevation — a maximum elevation change of 96 m.

The land around Castanhal is covered by artificial surfaces (56%) and grassland (25%) within 3 km, trees (60%) and grassland (36%) within 16 km, and trees (65%) within 80 km.

3 km
46 m
16 km
69 m
80 km
96 m
treesgrasslandartificial surfaceswatermangroves
August weather nearby: Santa Isabel do Pará 26 km · Santo Antônio do Tauá 28 km · Bujaru 28 km · Benevides 36 km · Igarapé-Açu 39 km · Santa Maria do Pará 39 km · Santa Bárbara do Pará 42 km · São Domingos do Capim 46 km

Brazil travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / N
127 / 220 V · 60 Hz
Prices
≈ 46% of US
price level, 2025
GDP per capita
$10,713
2025
Happiness
6.6 / 10
World Happiness, 2025
Safe drinking water
89%
of population, 2024
Homicide rate
19.3
per 100k, 2023
Road deaths
16
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 482
Religion
Roman Catholic 57%Evangelical 27%none 9%other 4%

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 Castanhal (-1.2939°, -47.9264°, elevation 46 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).