Chascomús weather in December

In December, Chascomús sees average daytime highs of 27°C and overnight lows near 16°C, with 81 mm of rain across 8.7 wet days and about 14.4 hours of daylight. It is the 3rd-warmest and 7th-wettest month of the year here.

Highs climb over the month, from about 26°C in the first days to 28°C by the end. The sky is clear or mostly clear about 48% of the time in December, and the air most often feels dry.

Daylight stretches from about 14 h 12 min at the start of December to 14 h 24 min by month's end. Set against the rest of the year, December is Chascomús's 2nd-clearest and 4th-windiest month. For the whole year in context, see Chascomús's year-round climate.

Daytime high
27°
3rd warmest
Overnight low
16°
10th coldest
Rainfall
81 mm
8.7 wet days
Daylight
14 h 24 min
5:36 AM – 8:00 PM
Cloud cover
45%
2nd clearest
Wind
14 km/h
4th windiest
Solar energy
7.37 kWh/m²
Travel score
6.9
out of 10

Chascomús is city in Argentina.

Founded
1779

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 26°C in the first days to 28°C by the end.

A typical December day in Chascomús reaches about 27°C in the afternoon and slips back to 16°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 22°C and 32°C. Set against its neighbours, December runs about 3°C warmer than November and about 1°C cooler than January.

10°15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12615
22615
32615
42615
52615
62615
72615
82615
92615
102715
112715
122716
132716
142716
152716
162716
172716
182716
192716
202816
212817
222817
232817
242817
252817
262817
272817
282817
292817
302817
312818

Chascomús weather by month

How December compares with the rest of the year at a glance. December is the 3rd-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 18°888.114.16.3
Feb27° / 17°918.213.36.8
Mar25° / 16°857.712.37.4
Apr22° / 12°877.311.17.2
May18° / 57610.16.3
Jun15° / 655.79.64.9
Jul14° / 616.39.84.4
Aug16° / 656.410.75.5
Sep18° / 72711.86.2
Oct21° / 11°1019.112.96.6
Nov24° / 14°888.313.97.2
Dec27° / 16°818.714.46.9

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 48% 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 36%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16139
26238
36238
46238
56337
66337
76337
86337
96337
106337
116337
126337
136337
146337
156337
166337
176436
186436
196436
206436
216535
226535
236535
246535
256535
266436
276436
286436
296436
306436
316436

Chance of precipitation in December

Any precipitation

Chascomús gets around 81 mm of rain over 8.7 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 28% and peaks near 29% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
126
226
326
427
527
627
727
828
928
1028
1128
1228
1328
1429
1529
1629
1729
1829
1929
2029
2129
2229
2329
2429
2529
2628
2728
2828
2928
3028
3128

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the dry band about 31% of days. Sticky, muggy-or-worse air turns up on roughly 16% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
143262560
243262560
343252560
442252670
542252670
641252670
740262680
839262780
938262780
1037262781
1136262891
1235272991
1334262991
14332630101
15322630101
16312631111
17302531121
18282531142
19272432152
20262332162
21252333182
22242233192
23232133203
24222033223
25212033233
26211933243
27201933254
28191933254
29181933264
30181933274
31171932274

Wind in December

Winds average 14 km/h in December.

Across December, daily wind ranges from about 13 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
114light breeze
214light breeze
314light breeze
414light breeze
514light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2814light breeze
2914light breeze
3013light breeze
3113light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 14 h 12 min at the start of December to 14 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 12 minutes over December. Sunrise moves from 5:35 AM to 5:44 AM, and sunset from 7:49 PM to 8:06 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.25:357:49
214.25:357:50
314.35:357:50
414.35:357:51
514.35:357:52
614.35:357:53
714.35:357:54
814.35:357:54
914.35:357:55
1014.35:357:56
1114.45:357:57
1214.45:357:57
1314.45:367:58
1414.45:367:59
1514.45:367:59
1614.45:368:00
1714.45:378:01
1814.45:378:01
1914.45:378:02
2014.45:388:02
2114.45:388:03
2214.45:398:03
2314.45:398:04
2414.45:408:04
2514.45:408:05
2614.45:418:05
2714.45:418:05
2814.45:428:06
2914.45:438:06
3014.45:438:06
3114.45:448:06

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 7.37 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 2.16 kWh/m² to a high of 7.37 kWh/m² in December across the year — December's 7.37 kWh/m² sits near the top of that range.

02468151015202531
Solar energy (kWh/m²)Level
17.2Intense
27.2Intense
37.3Intense
47.3Intense
57.3Intense
67.3Intense
77.3Intense
87.3Intense
97.3Intense
107.3Intense
117.4Intense
127.4Intense
137.4Intense
147.4Intense
157.4Intense
167.4Intense
177.4Intense
187.4Intense
197.4Intense
207.4Intense
217.4Intense
227.4Intense
237.4Intense
247.3Intense
257.3Intense
267.3Intense
277.3Intense
287.3Intense
297.3Intense
307.3Intense
317.3Intense
Planning a trip in December

Is December a good time to visit Chascomús?

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

6.9
Sightseeing
4th-best month of the year
7.1
Beach & pool
2nd-best month of the year

December is a reasonable time to visit Chascomús for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Chascomús in December

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

In December, Chascomús sees daytime highs around 27°C and nights near 16°C. Pack light clothes and sun protection. Worth having: rain gear. About 9 days see rain.

light clothessun protectionrain gear

Sea temperature near Chascomús in December

The nearest coast averages about 22°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 66 km away) is warmest in January at about 23°C and coldest in July near 11°C.

It's comfortable for a long swim from Nov 28 to Apr 4 — about 4.2 months when the water holds above 20°C.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan23Refreshing
Feb23Refreshing
Mar22Refreshing
Apr19Cool
May16Cool
Jun13Bracing
Jul11Bracing
Aug11Bracing
Sep13Bracing
Oct16Cool
Nov19Cool
Dec22Refreshing

UV index in Chascomús in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December 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 Chascomús peaks around January 14 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 20 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateHighVery highExtremeJan 14UV 12Jun 20UV 2
UV index (midday)Level
Jan12Extreme
Feb11Extreme
Mar10Very high
Apr6High
May3Moderate
Jun2Moderate
Jul3Moderate
Aug4Moderate
Sep6High
Oct7Very high
Nov11Extreme
Dec12Extreme
Location & terrain

Where is Chascomús?

Chascomús sits at 35.6°S, 58.0°W, 19 m above sea level, in Argentina. The nearest listed city is General Belgrano, 48 km away.

Topography around Chascomús

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

Within 3 km, the terrain around Chascomús has only modest variations in elevation — a maximum elevation change of 23 m around an average of 9 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 33 m; within 80 km, only modest variations in elevation — a maximum elevation change of 56 m.

The land around Chascomús is covered by water (46%) and artificial surfaces (23%) within 3 km, grassland (49%) and cropland (36%) within 16 km, and grassland (58%) and cropland (31%) within 80 km.

3 km
23 m
16 km
33 m
80 km
56 m
treesgrasslandcroplandartificial surfaceswaterwetland
December weather nearby: General Belgrano 48 km · Coronel Brandsen 50 km · Magdalena 71 km · San Vicente 72 km · La Plata 73 km · San Miguel del Monte 74 km · Berisso 79 km · Ensenada 80 km

Argentina travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / I
220 V · 50 Hz
Prices
≈ 46% of US
price level, 2025
GDP per capita
$14,898
2025
Happiness
6.4 / 10
World Happiness, 2025
Homicide rate
4.5
per 100k, 2023
Road deaths
14.1
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
High
EF EPI 575
Religion
Roman Catholic 63%none 19%Evangelical 15%Jehovah's Witness and Church of Jesus Christ 1%

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 Chascomús (-35.5768°, -58.0121°, elevation 19 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).