General José de San Martín weather in December

In December, General José de San Martín sees average daytime highs of 32°C and overnight lows near 21°C, with 150 mm of rain across 10.8 wet days and about 13.6 hours of daylight. It is the 2nd-warmest and 4th-wettest month of the year here.

Highs climb over the month, from about 31°C in the first days to 32°C by the end. The sky is clear or mostly clear about 43% of the time in December, and the air most often feels oppressive.

Daylight stretches from about 13 h 30 min at the start of December to 13 h 36 min by month's end. Set against the rest of the year, December is General José de San Martín's 7th-clearest and 7th-windiest month. For the whole year in context, see General José de San Martín's year-round climate.

Daytime high
32°
2nd warmest
Overnight low
21°
10th coldest
Rainfall
150 mm
10.8 wet days
Daylight
13 h 42 min
6:04 AM – 7:43 PM
Cloud cover
51%
7th clearest
Wind
12 km/h
7th windiest
Solar energy
6.79 kWh/m²
Travel score
4.2
out of 10

General José de San Martín is city in Chaco, Argentina.

Density
398/km²
people per km²

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 31°C in the first days to 32°C by the end.

A typical December day in General José de San Martín reaches about 32°C in the afternoon and slips back to 21°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 36°C. Set against its neighbours, December runs about 2°C warmer than November and about 1°C cooler than January.

15°20°25°30°35°40°151015202531
Avg high (°C)Avg low (°C)
13020
23120
33120
43120
53120
63120
73120
83121
93121
103121
113121
123121
133221
143221
153221
163221
173221
183221
193222
203222
213222
223222
233222
243222
253222
263222
273222
283222
293322
303322
313322

How December really feels in General José de San Martín

Once humidity and wind are folded in, December averages 28 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
28
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.

General José de San Martín weather by month

How December compares with the rest of the year at a glance. December is the 2nd-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan33° / 22°11911.313.53.7
Feb32° / 22°12610.712.94.1
Mar30° / 20°1241112.25.0
Apr27° / 18°1511011.46.5
May23° / 14°948.910.77.1
Jun22° / 13°707.810.46.9
Jul21° / 11°536.510.57.3
Aug24° / 13°586.411.17.8
Sep26° / 15°87811.87.2
Oct28° / 18°15411.312.65.9
Nov30° / 19°16210.713.35.2
Dec32° / 21°15010.813.64.2

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 43% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 16% of December, with mostly cloudy or overcast conditions the remaining 41%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15545
25545
35644
45743
55743
65842
75941
85941
96040
106139
116139
126238
136238
146337
156337
166337
176337
186337
196238
206238
216139
226040
235941
245842
255842
265743
275743
285644
295644
305644
315743

Chance of precipitation in December

Any precipitation

General José de San Martín gets around 150 mm of rain over 10.8 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 35% and peaks near 37% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
136
236
335
435
534
634
734
833
933
1033
1133
1233
1333
1434
1534
1634
1735
1835
1935
2036
2136
2236
2337
2437
2537
2637
2737
2837
2936
3036
3135

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 38% of days. Sticky, muggy-or-worse air turns up on roughly 71% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
15102231302
2492231312
3492231313
4492230323
5492130323
6492130333
7482130333
8482129343
9482129343
10482129353
11482028354
12482028364
13482028364
14482028374
15381928374
16381928385
17381827385
18381827395
19281727406
20281726416
21271626417
22271626428
23171526438
24171525439
251715254310
261714254211
271714254212
281714244213
291713244213
301713244114
311713244114

Wind in December

Winds average 12 km/h in December.

Across December, daily wind ranges from about 12 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
112light breeze
212light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712light breeze
812light breeze
912calm
1012light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412calm
2512calm
2612calm
2712calm
2812calm
2912calm
3012calm
3112calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 13 h 30 min at the start of December to 13 h 36 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 6:01 AM to 6:11 AM, and sunset from 7:34 PM to 7:50 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.56:017:34
213.66:017:34
313.66:017:35
413.66:017:36
513.66:017:36
613.66:017:37
713.66:017:38
813.66:027:38
913.66:027:39
1013.66:027:40
1113.66:027:40
1213.66:037:41
1313.66:037:41
1413.66:037:42
1513.76:037:43
1613.76:047:43
1713.76:047:44
1813.76:057:44
1913.76:057:45
2013.76:057:45
2113.76:067:46
2213.76:067:46
2313.76:077:47
2413.76:077:47
2513.76:087:48
2613.76:087:48
2713.76:097:48
2813.76:097:49
2913.76:107:49
3013.66:117:50
3113.66:117:50

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 6.79 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 2.65 kWh/m² to a high of 6.79 kWh/m² in January across the year — December's 6.79 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
16.6Intense
26.6Intense
36.6Intense
46.6Intense
56.6Intense
66.7Intense
76.7Intense
86.7Intense
96.7Intense
106.7Intense
116.8Intense
126.8Intense
136.8Intense
146.8Intense
156.9Intense
166.9Intense
176.9Intense
186.9Intense
196.9Intense
206.9Intense
216.9Intense
226.9Intense
236.9Intense
246.9Intense
256.9Intense
266.9Intense
276.9Intense
286.9Intense
296.9Intense
306.9Intense
316.9Intense
Planning a trip in December

Is December a good time to visit General José de San Martín?

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

4.2
Sightseeing
10th-best month of the year
6.5
Beach & pool
7th-best month of the year

December is a reasonable time to visit General José de San Martín for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for General José de San Martín in December

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

In December, General José de San Martín sees daytime highs around 32°C and nights near 21°C. Pack light clothes and sun protection. Worth having: rain gear. About 11 days see rain.

light clothessun protectionrain gear

UV index in General José de San Martín in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in General José de San Martín peaks around January 18 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 17 at about 4 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighModerateVery highExtremeJan 18UV 14Jul 17UV 4
UV index (midday)Level
Jan15Extreme
Feb14Extreme
Mar12Extreme
Apr8Very high
May6High
Jun5Moderate
Jul4Moderate
Aug5Moderate
Sep8Very high
Oct7Very high
Nov12Extreme
Dec13Extreme

Air quality in General José de San Martín 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 General José de San Martín is worst in September — around 22 µg/m³ PM2.5 (moderate), about 3.3× the cleanest month (May, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1321 µg/m³May 137 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb10Good
Mar10Good
Apr7Good
May7Good
Jun7Good
Jul10Good
Aug19Moderate
Sep22Moderate
Oct14Moderate
Nov10Good
Dec8Good
Location & terrain

Where is General José de San Martín?

General José de San Martín sits at 26.5°S, 59.3°W, 62 m above sea level, in Argentina. The nearest listed city is Machagai, 83 km away.

Topography around General José de San Martín

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of General José de San Martín.

Within 3 km, the terrain around General José de San Martín has only modest variations in elevation — a maximum elevation change of 13 m around an average of 75 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 27 m; within 80 km, only modest variations in elevation — a maximum elevation change of 54 m.

The land around General José de San Martín is covered by grassland (49%) and trees (28%) within 3 km, grassland (50%) and trees (47%) within 16 km, and trees (53%) and grassland (44%) within 80 km.

3 km
13 m
16 km
27 m
80 km
54 m
treesgrasslandcroplandartificial surfaceswetland
December weather nearby: Machagai 83 km · Pirané 92 km · Quitilipi 94 km · Fontana 103 km · Pilar 109 km · Resistencia 109 km · Tres Isletas 111 km · Barranqueras 112 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 General José de San Martín (-26.5364°, -59.3414°, elevation 62 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).