Três Rios weather in December

In December, Três Rios sees average daytime highs of 29°C and overnight lows near 20°C, with 236 mm of rain across 21.3 wet days and about 13.3 hours of daylight. It is the 4th-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 10% of the time in December, and the air most often feels muggy.

Daylight stretches from about 13 h 18 min at the start of December to 13 h 18 min by month's end. Set against the rest of the year, December is Três Rios's 11th-clearest and 5th-windiest month. For the whole year in context, see Três Rios's year-round climate.

Daytime high
29°
4th warmest
Overnight low
20°
10th coldest
Rainfall
236 mm
21.3 wet days
Daylight
13 h 18 min
6:09 AM – 7:29 PM
Cloud cover
76%
11th clearest
Wind
7 km/h
5th windiest
Solar energy
5.48 kWh/m²
Travel score
4.2
out of 10

Três Rios 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 29°C through the month.

A typical December day in Três Rios reaches about 29°C in the afternoon and slips back to 20°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 32°C. Set against its neighbours, December runs about 1°C warmer than November and on par with January.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12819
22819
32820
42820
52820
62820
72820
82820
92820
102820
112820
122820
132820
142820
152920
162920
172920
182920
192920
202920
212920
222920
232920
242920
252920
262920
272920
282920
292920
302920
312920

Três Rios weather by month

How December compares with the rest of the year at a glance. December is the 4th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 20°23319.513.24.1
Feb30° / 20°15415.112.84.3
Mar29° / 20°14817.712.24.5
Apr27° / 18°579.611.56.4
May25° / 16°356.3117.4
Jun24° / 14°173.410.78.2
Jul24° / 14°183.710.88.2
Aug25° / 14°214.211.27.9
Sep26° / 16°598.711.96.8
Oct27° / 18°10713.712.55.8
Nov27° / 19°19818.813.14.8
Dec29° / 20°23621.313.34.2

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 10% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 14% of December, with mostly cloudy or overcast conditions the remaining 77%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12080
22080
31981
41981
51981
61981
71882
82080
92179
102179
112278
122278
132377
142476
152476
162674
172674
182773
192773
202773
212872
222872
232872
242773
252773
262575
272575
282476
292476
302476
312476

Chance of precipitation in December

Any precipitation

Três Rios gets around 236 mm of rain over 21.3 wet days in December, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 69% and peaks near 71% on the wettest days.

0%20%40%60%80%151015202531
Rain chance (%)
167
268
368
468
569
669
769
869
969
1069
1168
1268
1368
1468
1567
1667
1767
1867
1967
2067
2168
2268
2368
2469
2569
2670
2770
2871
2971
3071
3170

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the muggy band about 69% of days. Sticky, muggy-or-worse air turns up on roughly 83% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1527599
2526609
34256110
44246111
54236211
63226312
73216412
83206512
93196612
102186812
112176912
122176912
132167012
141157212
151157212
161147213
171137313
181137313
191127413
201127314
211117414
221117414
231107415
241107415
251107316
26197317
27197317
28197218
29097318
300107119
310107119

Wind in December

Winds average 7 km/h in December.

Across December, daily wind ranges from about 7 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
18calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 13 h 18 min at the start of December to 13 h 18 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 6:05 AM to 6:16 AM, and sunset from 7:20 PM to 7:36 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.36:057:20
213.36:057:21
313.36:057:22
413.36:057:22
513.36:067:23
613.36:067:23
713.36:067:24
813.36:067:25
913.36:067:25
1013.36:077:26
1113.36:077:27
1213.36:077:27
1313.36:087:28
1413.36:087:28
1513.36:087:29
1613.36:097:29
1713.36:097:30
1813.36:097:30
1913.46:107:31
2013.46:107:31
2113.46:117:32
2213.46:117:32
2313.46:127:33
2413.46:127:33
2513.46:137:34
2613.36:137:34
2713.36:147:35
2813.36:147:35
2913.36:157:35
3013.36:157:36
3113.36:167:36

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 5.48 kWh/m².

For context, solar energy here swings from a low near 3.41 kWh/m² to a high of 5.9 kWh/m² in February across the year — December's 5.48 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.2Bright
25.2Bright
35.2Bright
45.3Bright
55.3Bright
65.3Bright
75.3Bright
85.3Bright
95.3Bright
105.3Bright
115.3Bright
125.4Bright
135.4Bright
145.4Bright
155.5Bright
165.5Bright
175.5Bright
185.5Bright
195.5Bright
205.6Bright
215.6Bright
225.6Bright
235.6Bright
245.6Bright
255.6Bright
265.6Bright
275.6Bright
285.6Bright
295.6Bright
305.6Bright
315.6Bright
Planning a trip in December

Hazard calendar for Três Rios

In seasonPeak

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

Três Rios's monsoon runs October–March, when most of the year's rain falls.

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

Is December a good time to visit Três Rios?

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

4.2
Sightseeing
11th-best month of the year
5.0
Beach & pool
12th-best month of the year

December is a reasonable time to visit Três Rios for sightseeing.

What to pack for Três Rios in December

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

In December, Três Rios sees daytime highs around 29°C and nights near 20°C. Pack light clothes and rain gear. Worth having: sun protection. About 21 days see rain.

light clothesrain gearsun protection

UV index in Três Rios in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks 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 Três Rios peaks around February 9 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 10 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighVery highExtremeFeb 9UV 15Jul 10UV 6
UV index (midday)Level
Jan15Extreme
Feb15Extreme
Mar13Extreme
Apr10Very high
May7High
Jun6High
Jul6High
Aug8Very high
Sep8Very high
Oct12Extreme
Nov14Extreme
Dec14Extreme

Air quality in Três Rios 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 Três Rios is worst in September — around 22 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (January, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1521 µg/m³Jan 1111 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb11Good
Mar12Good
Apr13Moderate
May15Moderate
Jun15Moderate
Jul14Moderate
Aug16Moderate
Sep22Moderate
Oct14Moderate
Nov12Good
Dec11Good
Location & terrain

Where is Três Rios?

Três Rios sits at 22.1°S, 43.2°W, 276 m above sea level, in Brazil. The nearest listed city is Paraíba do Sul, 10 km away.

Topography around Três Rios

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

Within 3 km, the terrain around Três Rios has significant variations in elevation — a maximum elevation change of 408 m around an average of 338 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 655 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,252 m.

The land around Três Rios is covered by grassland (52%), trees (24%) and artificial surfaces (22%) within 3 km, grassland (59%) and trees (37%) within 16 km, and trees (49%) and grassland (45%) within 80 km.

3 km
408 m
16 km
655 m
80 km
2,252 m
treesgrasslandartificial surfaceswater
December weather nearby: Paraíba do Sul 10 km · São José do Vale do Rio Preto 30 km · Sapucaia 33 km · Paty do Alferes 41 km · Teresópolis 41 km · Juiz de Fora 42 km · São Pedro 42 km · Petrópolis 43 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 Três Rios (-22.1167°, -43.2092°, elevation 276 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).