Rosario climate
Rosario (Argentina) has a humid subtropical climate (Köppen Cfa). The average temperature over the year is 18 °C64 °F, and about 1,091 mm43 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Rosario climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 3391 | 1966 | 2679 | 1234.8 | 0 |
| Feb | 3187 | 1864 | 2476 | 1395.5 | 0 |
| Mar | 2882 | 1560 | 2271 | 1485.8 | 0 |
| Apr | 2475 | 1253 | 1864 | 1114.4 | 0 |
| May | 1966 | 847 | 1457 | 522.0 | 0 |
| Jun | 1661 | 541 | 1151 | 220.9 | 1 |
| Jul | 1660 | 440 | 1050 | 261.0 | 3 |
| Aug | 1865 | 642 | 1254 | 381.5 | 1 |
| Sep | 2271 | 847 | 1559 | 582.3 | 0 |
| Oct | 2578 | 1153 | 1865 | 1234.8 | 0 |
| Nov | 2984 | 1558 | 2271 | 1094.3 | 0 |
| Dec | 3289 | 1763 | 2476 | 1425.6 | 0 |
| Year | 3391 | 440 | 1864 | 1,09143 | 6 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 61% | 50% | 7.2 | 14:06 |
| Feb | 67% | 58% | 6.1 | 13:19 |
| Mar | 71% | 46% | 5.2 | 12:23 |
| Apr | 75% | 49% | 3.9 | 11:19 |
| May | 80% | 54% | 2.9 | 10:27 |
| Jun | 80% | 52% | 2.5 | 9:59 |
| Jul | 78% | 53% | 2.7 | 10:10 |
| Aug | 74% | 47% | 3.6 | 10:55 |
| Sep | 69% | 48% | 4.7 | 11:56 |
| Oct | 68% | 51% | 5.6 | 12:58 |
| Nov | 63% | 46% | 6.9 | 13:53 |
| Dec | 60% | 49% | 7.2 | 14:19 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Rosario is like
The warmest month is January, with an average high of 33 °C91 °F and a low of 19 °C66 °F. The coldest is July, when highs average 16 °C60 °F and lows 4 °C40 °F. There is a clear seasonal cycle, with 15.9 °C28.6 °F between the average temperature of the warmest and the coolest month.
It is wet, with about 1,091 mm43 in of precipitation per year. The wettest three-month stretch is January–March, which brings 38% of the annual total. The wettest month is March (148 mm5.8 in), the driest is June (22 mm0.9 in).
Relative humidity ranges from 60% in December to 80% in June. The clearest skies (lowest average cloud amount, 46%) are typical of March. Average wind speed near the ground ranges from 7 km/h (4 mph) in March to 9 km/h (5 mph) in October. Daylight lasts from about 10.0 hours in June to 14.3 hours in December.
Best time to visit Rosario
Based on these averages, the most comfortable months for sightseeing and outdoor activities are May and August and September: average highs of 18 °C65 °F to 22 °C71 °F with 38 mm1.5 in to 58 mm2.3 in of precipitation per month.
The most challenging month is January, which is hot, with average highs of 33 °C91 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Rosario
- Summer (December–February) — highs 3187 to 33 °C91 °F, lows 1763 to 19 °C66 °F, about 135 mm5.3 in of precipitation a month. Pack very light, breathable clothing, a sun hat and plenty of water, an extra layer for the cooler mornings and evenings and an umbrella or light rain jacket.
- Autumn (March–May) — highs 1966 to 28 °C82 °F, lows 847 to 15 °C60 °F, about 104 mm4.1 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket, an extra layer for the cooler mornings and evenings and an umbrella or light rain jacket.
- Winter (June–August) — highs 1660 to 18 °C65 °F, lows 440 to 6 °C42 °F, about 29 mm1.1 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket and an extra layer for the cooler mornings and evenings.
- Spring (September–November) — highs 2271 to 29 °C84 °F, lows 847 to 15 °C58 °F, about 96 mm3.8 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses, an extra layer for the cooler mornings and evenings and an umbrella or light rain jacket.
How Rosario compares
Compared with Buenos Aires, about 279 km to the southeast, Rosario has practically the same average temperature and receives a similar amount of precipitation. The difference is largest in November (1.4 °C2.5 °F warmer).
Of the 31 places in Argentina covered by World Climates, Rosario is the 15th warmest by annual mean temperature and the 11th wettest by annual precipitation. See all of them on the Argentina climate page.
Places in other countries with the most similar temperature and rainfall pattern: Richmond (New South Wales) (Australia, Cfa), Salto (Uruguay, Cfa) and Maitland (Australia, Cfa).
Nearby places
- San Nicolás de los Arroyos 59 km · 17 °C63 °F · 1,178 mm46 in
- Santa Fe 144 km · 19 °C67 °F · 1,153 mm45 in
- Merlo 260 km · 17 °C62 °F · 1,108 mm44 in
- Laferrere 276 km · 16 °C62 °F · 1,069 mm42 in
- Buenos Aires 279 km · 18 °C64 °F · 1,103 mm43 in
- Concordia 301 km · 19 °C66 °F · 1,414 mm56 in
- Berazategui 302 km · 17 °C62 °F · 1,072 mm42 in
- Salto 306 km · 19 °C66 °F · 1,414 mm56 in
Frequently asked questions
What is the warmest month in Rosario?
January is the warmest month in Rosario, with an average high of 33 °C (91 °F) and an average low of 19 °C (66 °F).
What is the coldest month in Rosario?
July is the coldest month, with an average high of 16 °C (60 °F) and an average low of 4 °C (40 °F).
When does it rain the most in Rosario?
March is the wettest month with about 148 mm (5.8 in) of precipitation; June is the driest with about 22 mm (0.9 in).
What is the best time to visit Rosario?
Judging by long-term averages, the most comfortable months are May and August and September.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.