Santarém weather in December

In December, Santarém sees average daytime highs of 30°C and overnight lows near 25°C, with 233 mm of rain across 21.7 wet days and about 12.1 hours of daylight. It is the 5th-warmest and 6th-wettest month of the year here.

Day-to-day highs hold fairly steady near 30°C through the month. The sky is clear or mostly clear about 14% of the time in December, and the air most often feels oppressive.

Daylight stretches from about 12 h 06 min at the start of December to 12 h 06 min by month's end. Set against the rest of the year, December is Santarém's 7th-clearest and 4th-windiest month. For the whole year in context, see Santarém's year-round climate.

Daytime high
30°
5th warmest
Overnight low
25°
9th coldest
Rainfall
233 mm
21.7 wet days
Daylight
12 h 06 min
6:31 AM – 6:39 PM
Cloud cover
72%
7th clearest
Wind
10 km/h
4th windiest
Solar energy
5.42 kWh/m²
Travel score
3.4
out of 10

Santarém is human settlement in Brazil.

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 30°C through the month.

A typical December day in Santarém reaches about 30°C in the afternoon and slips back to 25°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 32°C. Set against its neighbours, December runs about 1°C cooler than November and about 1°C warmer than January.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13126
23126
33126
43126
53126
63126
73126
83126
93126
103126
113126
123126
133126
143126
153026
163025
173025
183025
193025
203025
213025
223025
233025
243025
253025
263025
273025
283025
293025
303025
313025

How December really feels in Santarém

Once humidity and wind are folded in, December 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 December is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Santarém weather by month

How December compares with the rest of the year at a glance. December is the 5th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 25°40928.212.13.1
Feb29° / 25°38725.812.13.1
Mar29° / 25°48829.3123.0
Apr29° / 25°45029.211.92.9
May29° / 25°36529.611.93.0
Jun29° / 24°18724.811.93.6
Jul30° / 25°11419.211.94.3
Aug31° / 25°741311.94.5
Sep32° / 26°6810.5124.2
Oct32° / 26°10711.912.13.9
Nov31° / 26°14916.612.13.6
Dec30° / 25°23321.712.13.4

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 14% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 15% of December, with mostly cloudy or overcast conditions the remaining 70%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13961
23862
33763
43763
53664
63565
73565
83466
93367
103367
113268
123169
133070
143070
152971
162971
172674
182674
192674
202674
212575
222575
232575
242575
252575
262575
272575
282575
292575
302575
312575

Chance of precipitation in December

Any precipitation

Santarém gets around 233 mm of rain over 21.7 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 71% and peaks near 85% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%100%151015202531
Rain chance (%)
155
256
356
457
558
659
760
861
962
1064
1165
1266
1368
1469
1571
1672
1773
1874
1975
2076
2177
2278
2379
2480
2581
2681
2782
2883
2984
3084
3185

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December 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
Oppressive (%)Miserable (%)
1946
2955
3955
4964
5964
6964
7973
8973
9973
10982
11982
12982
13982
14982
15982
16982
17982
18982
19982
20982
21982
22973
23973
24973
25973
26973
27973
28973
29973
30973
31973

Wind in December

Winds average 10 km/h in December.

Across December, daily wind ranges from about 9 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
309calm
319calm

Sunrise & sunset in December

DaylightNight

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

Days grow by about 0 minutes over December. Sunrise moves from 6:25 AM to 6:38 AM, and sunset from 6:33 PM to 6:46 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.16:256:33
212.16:256:33
312.16:256:33
412.16:266:34
512.16:266:34
612.16:276:35
712.16:276:35
812.16:276:36
912.16:286:36
1012.16:286:36
1112.16:296:37
1212.16:296:37
1312.16:296:38
1412.16:306:38
1512.16:306:39
1612.16:316:39
1712.16:316:40
1812.16:326:40
1912.16:326:41
2012.16:336:41
2112.16:336:42
2212.16:346:42
2312.16:346:43
2412.16:356:43
2512.16:356:43
2612.16:356:44
2712.16:366:44
2812.16:366:45
2912.16:376:45
3012.16:376:46
3112.16:386:46

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 5.42 kWh/m².

For context, solar energy here swings from a low near 4.39 kWh/m² to a high of 6.38 kWh/m² in October across the year — December's 5.42 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.8Bright
25.8Bright
35.8Bright
45.7Bright
55.7Bright
65.7Bright
75.7Bright
85.6Bright
95.6Bright
105.6Bright
115.5Bright
125.5Bright
135.5Bright
145.4Bright
155.4Bright
165.4Bright
175.3Bright
185.3Bright
195.3Bright
205.3Bright
215.2Bright
225.2Bright
235.2Bright
245.2Bright
255.1Bright
265.1Bright
275.1Bright
285.1Bright
295.1Bright
305.0Bright
315.0Bright
Planning a trip in December

Hazard calendar for Santarém

In seasonPeak

In December, Santarém sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Santarém's rainy season runs December–May, when most of the year's rain falls.

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

Is December a good time to visit Santarém?

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

3.4
Sightseeing
7th-best month of the year
4.8
Beach & pool
6th-best month of the year

December is a weaker month for outdoor sightseeing in Santarém.

What to pack for Santarém in December

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

In December, Santarém sees daytime highs around 30°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 22 days see rain.

light clothesrain gearsun protection

UV index in Santarém in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Santarém peaks around March 13 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 12 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 highExtremeMar 13UV 15Jul 12UV 10
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar15Extreme
Apr14Extreme
May11Extreme
Jun10Very high
Jul10Very high
Aug10Extreme
Sep11Extreme
Oct12Extreme
Nov10Extreme
Dec11Extreme

Air quality in Santarém in December

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Santarém is worst in November — around 31 µg/m³ PM2.5 (moderate), about 3.5× the cleanest month (June, 9 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateNov 1530 µg/m³Jun 209 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb16Moderate
Mar16Moderate
Apr14Moderate
May10Good
Jun9Good
Jul9Good
Aug12Good
Sep15Moderate
Oct24Moderate
Nov31Moderate
Dec23Moderate
Location & terrain

Where is Santarém?

Santarém sits at 2.4°S, 54.7°W, 51 m above sea level, in Brazil. The nearest listed city is Mojuí dos Campos, 28 km away.

Topography around Santarém

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

Within 3 km, the terrain around Santarém has only modest variations in elevation — a maximum elevation change of 70 m around an average of 34 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 198 m; within 80 km, significant variations in elevation — a maximum elevation change of 281 m.

The land around Santarém is covered by artificial surfaces (65%) within 3 km, water (40%) and trees (34%) within 16 km, and trees (49%) and water (27%) within 80 km.

3 km
70 m
16 km
198 m
80 km
281 m
treesgrasslandartificial surfacesbare terrainwaterwetland
December weather nearby: Mojuí dos Campos 28 km · Belterra 33 km · Alenquer 56 km · Monte Alegre 85 km · Óbidos 107 km · Aveiro 147 km · Oriximiná 149 km · Prainha 154 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 Santarém (-2.4431°, -54.7083°, elevation 51 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. 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).