Costa Rica weather in December

In December, Costa Rica sees average daytime highs of 29°C and overnight lows near 21°C, with 217 mm of rain across 25.6 wet days and about 13.1 hours of daylight. It is the 7th-warmest and 2nd-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 hours at the start of December to 13 h 06 min by month's end. Set against the rest of the year, December is Costa Rica's 11th-clearest and 9th-windiest month. For the whole year in context, see Costa Rica's year-round climate.

Daytime high
29°
7th warmest
Overnight low
21°
11th coldest
Rainfall
217 mm
25.6 wet days
Daylight
13 h 06 min
5:55 AM – 7:02 PM
Cloud cover
77%
11th clearest
Wind
7 km/h
9th windiest
Solar energy
5.71 kWh/m²
Travel score
3.4
out of 10

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 Costa Rica reaches about 29°C in the afternoon and slips back to 21°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 32°C. Set against its neighbours, December runs on par with November and on par with January.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12921
22921
32921
42921
52921
62921
72921
82921
92921
102921
112921
122921
132921
142921
152921
162921
172921
182921
192921
202921
212921
222921
232921
242921
252921
262921
272921
282921
292921
302921
312921

How December really feels in Costa Rica

Once humidity and wind are folded in, December averages 0 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
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

December sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Costa Rica weather by month

How December compares with the rest of the year at a glance. December is the 7th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 21°25626.2133.3
Feb29° / 21°21523.612.63.3
Mar30° / 21°18123.812.13.6
Apr29° / 20°8112.411.65.0
May28° / 18°395.711.17.0
Jun28° / 17°182.410.97.9
Jul28° / 16°111.4117.6
Aug30° / 18°172.511.46.0
Sep31° / 20°678.711.94.5
Oct31° / 21°12918.512.43.7
Nov30° / 21°17522.212.93.5
Dec29° / 21°21725.613.13.4

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 76%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12773
22476
32476
42278
52278
62179
72080
82080
92179
102179
112278
122278
132278
142476
152476
162476
172674
182773
192773
202773
212872
222872
232773
242674
252674
262575
272575
282476
292476
302377
312278

Chance of precipitation in December

Any precipitation

Costa Rica gets around 217 mm of rain over 25.6 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 82% and peaks near 86% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%100%151015202531
Rain chance (%)
179
279
380
480
580
681
781
881
981
1081
1181
1280
1380
1481
1581
1681
1781
1881
1981
2082
2182
2283
2383
2484
2584
2685
2785
2885
2986
3086
3186

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 70% of days. Sticky, muggy-or-worse air turns up on roughly 95% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1367021
2257122
3257023
4256924
5256924
6256825
7156925
8156826
9156826
10156826
11156826
12156727
13156727
14156727
15156826
16156826
17156826
18147025
19147025
20147124
21137224
22137224
23137224
24027424
25027424
26027424
27027424
28027325
29027226
30027226
31027127

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 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
17calm
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 hours at the start of December to 13 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 6 minutes over December. Sunrise moves from 5:51 AM to 6:03 AM, and sunset from 6:53 PM to 7:09 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:516:53
213.05:516:54
313.05:526:55
413.15:526:55
513.15:526:56
613.15:526:56
713.15:526:57
813.15:536:57
913.15:536:58
1013.15:536:59
1113.15:546:59
1213.15:547:00
1313.15:547:00
1413.15:557:01
1513.15:557:01
1613.15:557:02
1713.15:567:02
1813.15:567:03
1913.15:577:03
2013.15:577:04
2113.15:587:04
2213.15:587:05
2313.15:597:05
2413.15:597:06
2513.15:597:06
2613.16:007:07
2713.16:017:07
2813.16:017:08
2913.16:027:08
3013.16:027:08
3113.16:037:09

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 5.71 kWh/m².

For context, solar energy here swings from a low near 4.17 kWh/m² to a high of 5.99 kWh/m² in October across the year — December's 5.71 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.7Bright
25.7Bright
35.7Bright
45.7Bright
55.7Bright
65.6Bright
75.6Bright
85.6Bright
95.6Bright
105.6Bright
115.6Bright
125.6Bright
135.6Bright
145.7Bright
155.7Bright
165.7Bright
175.7Bright
185.7Bright
195.8Bright
205.8Bright
215.8Bright
225.8Bright
235.8Bright
245.8Bright
255.8Bright
265.8Bright
275.7Bright
285.7Bright
295.7Bright
305.7Bright
315.7Bright
Planning a trip in December

Hazard calendar for Costa Rica

In seasonPeak

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

Costa Rica'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 Costa Rica?

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

3.4
Sightseeing
10th-best month of the year
4.4
Beach & pool
10th-best month of the year

December is a weaker month for outdoor sightseeing in Costa Rica.

What to pack for Costa Rica in December

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

In December, Costa Rica sees daytime highs around 29°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 26 days see rain.

light clothesrain gearsun protection

UV index in Costa Rica 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 Costa Rica peaks around January 22 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 21 at about 7 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeJan 22UV 15Jun 21UV 7
UV index (midday)Level
Jan15Extreme
Feb15Extreme
Mar14Extreme
Apr11Extreme
May8Very high
Jun7Very high
Jul8Very high
Aug9Very high
Sep9Very high
Oct10Extreme
Nov13Extreme
Dec14Extreme

Air quality in Costa Rica 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 Costa Rica is worst in September — around 24 µg/m³ PM2.5 (moderate), about 5.2× the cleanest month (June, 5 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1722 µg/m³Jun 125 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb7Good
Mar6Good
Apr5Good
May5Good
Jun5Good
Jul8Good
Aug10Good
Sep24Moderate
Oct12Moderate
Nov6Good
Dec6Good
Location & terrain

Where is Costa Rica?

Costa Rica sits at 18.5°S, 53.1°W, 646 m above sea level, in Brazil. The nearest listed city is Chapadão do Sul, 60 km away.

Topography around Costa Rica

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

Within 3 km, the terrain around Costa Rica has only modest variations in elevation — a maximum elevation change of 160 m around an average of 655 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 307 m; within 80 km, large variations in elevation — a maximum elevation change of 616 m.

The land around Costa Rica is covered by grassland (39%) and trees (22%) within 3 km, cropland (41%), grassland (28%) and trees (27%) within 16 km, and cropland (42%), grassland (31%) and trees (23%) within 80 km.

3 km
160 m
16 km
307 m
80 km
616 m
treesshrubsgrasslandcroplandartificial surfaceswater
December weather nearby: Chapadão do Sul 60 km · Mineiros 124 km · Alto Araguaia 137 km · Cassilândia 160 km · Jataí 166 km · Coxim 172 km · São Gabriel do Oeste 178 km · Rio Verde de Mato Grosso 185 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 Costa Rica (-18.5439°, -53.1292°, elevation 646 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).