La Unión in Summer

In summer (December, January and February), La Unión sees average daytime highs around 28°C and overnight lows near 17°C, with 263 mm of rain over about 25 wet days across the season. It is the warmest season of the year and the 2nd-wettest season.

Across summer, daytime highs hold fairly steady around 28°C. The sky is clear or mostly clear about 50% of the time across summer, and the air most often feels humid.

Summer is La Unión's 3rd-best season to visit on our travel score. For the whole year in context, see La Unión's year-round climate.

Avg daytime high
28°C
warmest season of the year
Avg overnight low
17°C
Rainfall
263 mm
25 wet days
Avg wind
13 km/h
Travel score
6.4
3rd-best season
Months
Dec · Jan · Feb

Temperature in La Unión in Summer

Average highAverage lowShaded bands: 10–90% of days

Across summer, daytime highs hold fairly steady around 28°C.

A typical summer day in La Unión reaches about 28°C and drops to 17°C overnight. The warmest of the three months is January, the coolest December.

10°20°30°DecJanFeb

La Unión weather by month

How the three summer months (December, January and February) compare with the rest of the year — the season's months are highlighted.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 18°897.914.16.0
Feb28° / 17°898.613.36.6
Mar26° / 16°817.212.37.4
Apr22° / 12°908.211.17.1
May18° / 596.110.26.4
Jun15° / 605.69.75.1
Jul14° / 596.19.94.6
Aug16° / 64610.75.8
Sep18° / 72711.86.4
Oct21° / 11°1069.412.96.7
Nov24° / 14°948.413.87.2
Dec28° / 16°868.614.36.7

Cloud cover in Summer

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 50% of the time across summer.

0%25%50%75%100%DecJanFeb

Chance of precipitation in Summer

Any precipitation

La Unión gets around 263 mm of rain over 25 wet days across summer. The line is the day-by-day chance of measurable precipitation.

0%10%20%30%40%DecJanFeb

Humidity in Summer

DryComfortableHumidMuggyOppressiveMiserable

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

0%25%50%75%100%DecJanFeb

Wind in Summer

Winds average 13 km/h across summer.

05101520DecJanFeb

Sunrise & sunset in Summer

DaylightNight

Daylight runs from about 14 h 12 min in early December to 12 h 54 min by late February. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMDecJanFeb

Solar energy in Summer

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across summer, about 7.0 kWh/m².

02468DecJanFeb
Planning a trip in summer

Is summer a good time to visit La Unión?

Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.

6.4
Sightseeing
3rd-best month of the year
7.3
Beach & pool
1st-best month of the year

summer is a reasonable time to visit La Unión for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for La Unión in Summer

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

In summer, La Unión sees daytime highs around 28°C and nights near 17°C. Pack light clothes and sun protection. Worth having: rain gear. About 25 days see rain.

light clothessun protectionrain gear

Sea temperature near La Unión in Summer

The nearest coast averages about 24°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 32 km away) is warmest in January at about 25°C and coldest in July near 13°C.

It's comfortable for a long swim from Nov 9 to Apr 20 — about 5.4 months when the water holds above 20°C.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swimcomfortable to swim
Sea temperature (°C)Comfort
Jan25Warm
Feb25Warm
Mar23Refreshing
Apr21Refreshing
May17Cool
Jun14Bracing
Jul13Bracing
Aug13Bracing
Sep15Cool
Oct18Cool
Nov21Refreshing
Dec23Refreshing

UV index in La Unión in Summer

LowModerateHighVery highExtreme

Clear-sky midday UV across summer averages 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 La Unión peaks around January 14 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 19 at about 3 (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 19UV 3
UV index (midday)Level
Jan13Extreme
Feb11Extreme
Mar10Very high
Apr6High
May3Moderate
Jun3Moderate
Jul3Moderate
Aug4Moderate
Sep6High
Oct8Very high
Nov11Extreme
Dec12Extreme

Air quality in La Unión in Summer

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in La Unión is worst in August — around 17 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (December, 9 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodAug 1316 µg/m³Dec 129 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb10Good
Mar11Good
Apr12Good
May14Moderate
Jun15Moderate
Jul16Moderate
Aug17Moderate
Sep14Moderate
Oct11Good
Nov10Good
Dec9Good
Location & terrain

Where is La Unión?

La Unión sits at 34.9°S, 58.5°W, 18 m above sea level, in Argentina. The nearest listed city is Tristán Suárez, 3.0 km away.

Topography around La Unión

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

Within 3 km, the terrain around La Unión has only modest variations in elevation — a maximum elevation change of 23 m around an average of 21 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 53 m; within 80 km, only modest variations in elevation — a maximum elevation change of 72 m.

The land around La Unión is covered by artificial surfaces (43%), trees (26%) and grassland (26%) within 3 km, grassland (41%) and artificial surfaces (27%) within 16 km, and grassland (35%) and cropland (28%) within 80 km.

3 km
23 m
16 km
53 m
80 km
72 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
Summer weather nearby: Tristán Suárez 3.0 km · Ezeiza 3.0 km · Burzaco 15 km · Adrogué 17 km · Lomas de Zamora 18 km · San Vicente 20 km · Banfield 20 km · Isidro Casanova 20 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 La Unión (-34.8756°, -58.5419°, elevation 18 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.