Rosario in Summer
In summer (December, January and February), Rosario sees average daytime highs around 29°C and overnight lows near 18°C, with 317 mm of rain over about 25 wet days across the season. It is the warmest season of the year and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 29°C. The sky is clear or mostly clear about 49% of the time across summer, and the air most often feels humid.
Summer is Rosario's weakest season of the year to visit on our travel score. For the whole year in context, see Rosario's year-round climate.
- Avg daytime high
- 29°C
- warmest season of the year
- Avg overnight low
- 18°C
- Rainfall
- 317 mm
- 25 wet days
- Avg wind
- 11 km/h
- Travel score
- 5.8
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Rosario in Summer
Across summer, daytime highs hold fairly steady around 29°C.
A typical summer day in Rosario reaches about 29°C and drops to 18°C overnight. The warmest of the three months is January, the coolest December.
Rosario 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.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 30° / 19° | 102 | 8.1 | 13.9 | 5.5 |
| Feb | 29° / 18° | 111 | 8.5 | 13.2 | 6.0 |
| Mar | 27° / 17° | 126 | 7.6 | 12.3 | 7.1 |
| Apr | 23° / 13° | 103 | 7.9 | 11.2 | 7.4 |
| May | 19° / 10° | 66 | 6 | 10.3 | 6.8 |
| Jun | 16° / 7° | 40 | 4.6 | 9.9 | 5.9 |
| Jul | 16° / 6° | 36 | 5 | 10 | 5.6 |
| Aug | 18° / 8° | 53 | 4.6 | 10.8 | 6.9 |
| Sep | 21° / 10° | 61 | 5.8 | 11.8 | 7.2 |
| Oct | 24° / 13° | 111 | 9.7 | 12.8 | 7.1 |
| Nov | 26° / 15° | 115 | 8.3 | 13.7 | 7.1 |
| Dec | 29° / 18° | 104 | 8.6 | 14.1 | 6.0 |
Cloud cover in Summer
The sky is clear or mostly clear about 49% of the time across summer.
Chance of precipitation in Summer
Rosario gets around 317 mm of rain over 25 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 11 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 hours in early December to 12 h 48 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 6.9 kWh/m².
Is summer a good time to visit Rosario?
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.
summer is a reasonable time to visit Rosario for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Rosario in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Rosario sees daytime highs around 29°C and nights near 18°C. Pack light clothes and sun protection. Worth having: rain gear. About 25 days see rain.
UV index in Rosario in Summer
Clear-sky midday UV across summer averages 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 Rosario peaks around January 15 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 21 at about 3 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 13 | 12 | 10 | 6 | 4 | 3 | 3 | 4 | 6 | 9 | 11 | 12 |
| Level | Extreme | Extreme | Extreme | High | Moderate | Moderate | Moderate | Moderate | High | Very high | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 13 | Extreme |
| Feb | 12 | Extreme |
| Mar | 10 | Extreme |
| Apr | 6 | High |
| May | 4 | Moderate |
| Jun | 3 | Moderate |
| Jul | 3 | Moderate |
| Aug | 4 | Moderate |
| Sep | 6 | High |
| Oct | 9 | Very high |
| Nov | 11 | Extreme |
| Dec | 12 | Extreme |
Air quality in Rosario in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Rosario is worst in August — around 20 µg/m³ PM2.5 (moderate), about 3.0× the cleanest month (April, 7 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 9 | 8 | 8 | 7 | 8 | 10 | 13 | 20 | 19 | 10 | 8 | 8 |
| Level | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Moderate | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 9 | Good |
| Feb | 8 | Good |
| Mar | 8 | Good |
| Apr | 7 | Good |
| May | 8 | Good |
| Jun | 10 | Good |
| Jul | 13 | Moderate |
| Aug | 20 | Moderate |
| Sep | 19 | Moderate |
| Oct | 10 | Good |
| Nov | 8 | Good |
| Dec | 8 | Good |
Where is Rosario?
Rosario sits at 32.9°S, 60.6°W, 38 m above sea level, in Argentina. The nearest listed city is Gobernador Gálvez, 9.0 km away.
Topography around Rosario
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Rosario.
Within 3 km, the terrain around Rosario has only modest variations in elevation — a maximum elevation change of 41 m around an average of 19 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 57 m; within 80 km, only modest variations in elevation — a maximum elevation change of 121 m.
The land around Rosario is covered by artificial surfaces (53%) and water (21%) within 3 km, wetland (30%) and grassland (20%) within 16 km, and cropland (58%) and wetland (24%) within 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
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 Rosario (-32.9468°, -60.6393°, elevation 38 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.