December Weather in Rosario, Argentina

Last updated: August 21, 2025

In December, Rosario, Argentina experiences a dynamic climate characterized by warm temperatures and a hint of festive cheer. With maximums soaring up to 38°C (100°F) and a comfortable average of 24°C (75°F), residents and visitors alike can enjoy the vibrant summer atmosphere. However, the month is not without its share of rain, recording an average precipitation of 69 mm (2.7 in) over 8 days, contributing to a relative humidity of 51%. This blend of warmth and occasional showers makes December a lively yet refreshing time to experience the charm of Rosario.

December Temperature in Rosario

In December, Rosario, Argentina, ushers in the heart of summer, showcasing a delightful range of temperatures that invite both adventure and relaxation. With minimums settling around 10°C (50°F) and averages reaching a pleasant 24°C (75°F), the city offers a warm embrace to visitors and locals alike. As the month progresses, temperatures can soar to a scorching maximum of 38°C (100°F), signaling the peak of summer's intensity. This gradual rise from the cooler temperatures of spring highlights a trend of increasing warmth, painting a vibrant picture of life in Rosario, where sunny days are perfect for exploring outdoor markets or lounging by the Paraná River.

December Weather in Rosario: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Rosario, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Rosario, December typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec777471665853515560647175
Data source: Temperature data for Rosario generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Rosario

In December, Rosario, Argentina, typically experiences a modest precipitation level of 69 mm (2.7 in), falling just below the year-end average. Like many months, rainfall is spread across about 8 days, offering a refreshing break from the summer heat while still allowing for ample sunshine. This pattern of intermittent showers continues the trend observed in November, where the city received 81 mm (3.2 in) across the same number of days. As the year wraps up, the steady accumulation reflects the region's transition into the summer wet season, with precipitation gradually increasing as daylight gives way to shorter, cooler nights. Thus, December serves as a bridge, showcasing a balanced mix of weather that supports both vibrant summer vegetation and the festive spirit of the holiday season.

December Precipitation Trends in Rosario

The chart displays monthly precipitation patterns in Rosario, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In Rosario, December typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec10563931317129293558638169
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Rosario

December in Rosario, Argentina, marks a transition back to lower humidity levels after a notably humid year. With humidity at 51%, the month sees a slight dip from the higher averages of November’s 56% and the more pronounced humidity levels peaking in the cooler months, specifically May’s 82% and April’s 76%. As the year winds down, the city’s climate reflects a gradual decrease, moving away from the heavy moisture of late spring and early winter months. This trend suggests that while December offers a reprieve from the highest humidity levels, Rosario remains characteristically humid, setting the stage for a typically warm and comfortable summer ahead.

December Average Humidity in Rosario

This chart illustrates the average monthly humidity levels in Rosario, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Rosario is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec48%55%64%76%82%77%62%59%62%52%56%51%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Rosario

In December, Rosario, Argentina experiences one of its most intense UV Index ratings at 14, classifying it in the extreme exposure category. This means that even a brief 10-minute exposure can lead to skin damage, mirroring the high UV levels seen in January and February. The trend throughout the year illustrates a sharp decline in UV intensity from the peak summer months, transitioning into a more moderate exposure by May and June. However, as the year draws to a close, it’s crucial for residents and visitors to remain vigilant against harmful UV radiation in December. For more detailed insights on UV exposure in Rosario, visit Rosario UV Index.

Maximum UV Index Levels in Rosario for December

The chart shows the monthly maximum UV Index (UVI) for Rosario in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In December, the maximum UV index in Rosario typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec141311854468111314
Data source: Rosario December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

December Sunshine in Rosario

In Rosario, Argentina, December bids farewell to the year with an impressive 378 hours of sunshine, the highest monthly total in the calendar. This sparkling start to summer contrasts sharply with the cooler, darker months of the year, particularly from May to August, which see sunlight hours dip below the 300-hour mark. Notably, December's daylight abundance sets the stage for a radiant transition into January and February, where sunshine flourishes further, showcasing the region’s climatic warmth. As the year unfolds, the trend emerges: a vibrant summer sun envelops Rosario, fostering longer days that invite outdoor celebrations and exploration, creating a delightful end to one year and a bright commencement for the next.

Monthly Sunshine Duration in Rosario: December Highlighted

The December sunshine duration represents the total number of hours Rosario experiences direct sunlight during the month of December, excluding cloudy or obstructed periods. This chart compares the sunshine duration of December with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec294h324h315h260h231h222h227h281h273h310h344h378h
Data source: Rosario December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Rosario During December

In Rosario, Argentina, December boasts a sunny disposition, with a striking 74% chance of enjoying clear skies. This favorable likelihood positions the month among the brighter periods of the year, trailing only behind the sun-soaked months of July and August. As the year draws to a close, December's sunny potential reflects a notable trend towards increased sunshine, especially when compared to the cooler months of June and March, which dip to around 47%. With the festive season coinciding with such promising weather, December in Rosario is not only a time for celebration but also a great opportunity to bask in the warmth of the Argentine sun.

Percentage of Sunny Days in December in Rosario

The chart illustrates the percentage of sunny days in Rosario throughout the year, with December highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Rosario experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec61%66%47%68%60%47%74%78%50%73%61%74%
Data source: Rosario December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Rosario in December

In Rosario, Argentina, the daylight duration experiences a captivating ebb and flow throughout the year, with December marking a vibrant peak. As summer sets in, residents bask in approximately 14 hours of daylight, mirroring the extended light of January. This sun-drenched month stands in sharp contrast to the shorter days of mid-winter, where June offers merely 9 hours of daylight. As the year progresses from the abundant light of December slowly to the depths of winter in June, daylight gradually decreases, showcasing a rhythmic cycle. Notably, after June, there’s a gentle return to longer days, with daylight creeping back up to 14 hours by the end of the year. This cyclical pattern reflects the dynamic relationship between the seasons and the length of daylight, making each month an invitation to experience nature's magnificent transitions.

Average Daylight Hours in Rosario for December

The chart illustrates the variation in daylight duration in Rosario throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec14h 1m13h 14m12h 14m11h 13m10h 23m9h 59m10h 12m10h 56m11h 54m12h 54m13h 49m14h 16m
Data source: Rosario daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Rosario

In December, the winds in Rosario, Argentina pick up a gentle pace, averaging 3.0 m/s (7 mph), mirroring the mild breezes of the preceding months. As the year winds down, the transition from the robust autumn gusts peaks in September at 3.8 m/s (9 mph) to the softer currents of late spring. Notably, December's wind speed ties with January's as one of the more tranquil months, suggesting a seasonal shift towards more serene conditions. This calming wind sets a picturesque backdrop for the vibrant holiday festivities, creating a delightful interplay of warmth and cool breezes that invite residents and visitors alike to enjoy the outdoors.

Average December Wind Speed in Rosario

The chart displays monthly wind speed patterns in Rosario, with values for each month shown alongside December's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how December's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.22.82.82.93.13.13.33.03.83.23.53.0 m/s
Data source: Rosario December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Rosario Compares to Other Months

Weather in Rosario varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Rosario, focusing on differences in temperature, rainfall, humidity, and UV levels.

December and January in Rosario present a warm and somewhat humid climate, with January typically experiencing slightly higher temperatures and precipitation. In December, temperatures range from a minimum of 10°C (50°F) at night to a maximum of 38°C (100°F) during the day, while January sees a minimum of 11°C (53°F) and a peak of 41°C (105°F). Precipitation also increases in January, totaling 105 mm (4.1 in) compared to December’s 69 mm (2.7 in), although both months have a similar number of rainy days, with December experiencing rain on 8 days and January on 7 days. Overall, January is warmer and wetter, offering a more humid experience than December. For more detailed information, check out Rosario weather in January.

December and February share similar average temperatures, both hovering around 24°C (75°F), but December experiences slightly higher maximum temperatures, reaching up to 38°C (100°F) compared to February's 36°C (98°F). While December sees more precipitation at 69 mm over 8 days, February has a relatively drier spell with 63 mm over 7 days. Additionally, February comes with a bit more humidity at 55%, compared to December's 51%. For more detailed insights into February weather, you can check Rosario weather in February.

When comparing the weather in December and March, notable differences in temperature and precipitation emerge. December typically sees milder conditions with average temperatures ranging from a minimum of 10°C (50°F) to a maximum of 38°C (100°F), while March experiences slightly cooler averages, with temperatures ranging from 7°C (44°F) to 35°C (95°F). Precipitation is also a factor; December receives 69 mm (2.7 in) over 8 days, whereas March has higher rainfall at 93 mm (3.6 in) across just 6 days. Additionally, March tends to be more humid, with an average humidity of 64% compared to December's 51%. For more detailed information, you can check Rosario weather in March.

December and April present distinctly different weather patterns. In December, temperatures range from a minimum of 10°C (50°F) to a maximum of 38°C (100°F), with an average temperature of 24°C (75°F). Humidity is moderate at 51%, and the month experiences a total precipitation of 69 mm (2.7 in) over about 8 days. In contrast, April brings cooler temperatures, with a minimum of 3°C (37°F) and a maximum of 33°C (91°F), averaging around 19°C (66°F). The humidity increases to 76%, and precipitation is more substantial, totaling 131 mm (5.2 in) over 7 days. For more detailed information, you can check Rosario weather in April.

In December, the weather is notably warmer, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 38°C (100°F) and an average of 24°C (75°F). The month experiences moderate precipitation, with about 69 mm (2.7 in) over eight days, and humidity levels averaging 51%. In contrast, May brings a cooler climate, characterized by temperatures ranging from a chilling -1°C (30°F) to a maximum of 28°C (83°F) and a more modest average of 14°C (58°F). While precipitation is slightly higher at 71 mm (2.8 in) over just six days, the humidity rises significantly to 82%, contributing to a much different weather experience. For a detailed look at the May weather, you can check Rosario weather in May.

In December, the weather is considerably warmer, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 38°C (100°F) and an average temperature of 24°C (75°F). This month also sees higher humidity at 51% and a total precipitation of 69 mm (2.7 in) over approximately 8 days. In contrast, June is much cooler, with temperatures varying from a chilly -2°C (28°F) to a maximum of 26°C (79°F), averaging at just 12°C (53°F). The humidity is higher at 77%, but it experiences significantly less rainfall, with only 29 mm (1.1 in) over about 3 days. For a detailed look at June's climate, visit Rosario weather in June.

December and July present contrasting weather patterns in terms of temperature and precipitation. December features much warmer temperatures, ranging from a minimum of 10°C (50°F) to a maximum of 38°C (100°F), while July is significantly cooler, with temperatures fluctuating between -4°C (24°F) and a max of 27°C (80°F). Additionally, December experiences higher precipitation levels at 69 mm (2.7 in) over 8 days, compared to July's relatively drier conditions with just 29 mm (1.2 in) over 6 days. Humidity levels are also notable, with December at 51% and July slightly higher at 62%. For more details on July weather, you can visit Rosario weather in July.

December and August present contrasting weather conditions. In December, temperatures range from a minimum of 10°C (50°F) to a maximum of 38°C (100°F), with an average of 24°C (75°F). This month experiences a higher level of humidity at 51% and more frequent rainfall, totaling 69 mm (2.7 in) over about 8 days. In stark contrast, August sees much cooler temperatures, with a minimum of -2°C (29°F) and a maximum of 31°C (88°F), averaging just 13°C (55°F). Precipitation is notably lower during this month, with only 35 mm (1.4 in) falling over 4 days and a slightly higher humidity level of 59%. For more details on weather during this month, check out Rosario weather in August.

In December, the weather is significantly warmer than in September, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 38°C (100°F) and an average of 24°C (75°F). In contrast, September experiences cooler temperatures, with a range from -1°C (31°F) to a maximum of 33°C (92°F) and an average of 16°C (60°F). Additionally, December sees more precipitation, with 69 mm (2.7 in) over 8 days, compared to September's 58 mm (2.3 in) over just 6 days. The humidity is also slightly higher in September at 62%, whereas December's humidity averages around 51%. For more detailed information on September weather, you can visit Rosario weather in September.

December in Rosario is notably warmer than October, boasting an average temperature of 24°C (75°F) compared to October's milder 18°C (65°F). While both months experience eight days of precipitation, December sees slightly more rainfall at 69 mm (2.7 in) versus October's 63 mm (2.5 in). Humidity levels are similar, with December at 51% and October at 52%. Overall, if you're looking for warmer weather, December is the better choice. For a more detailed look at October conditions, you can check out Rosario weather in October.

In comparing the weather between November and December, December tends to be slightly warmer with average temperatures reaching 24°C (75°F) compared to November's average of 22°C (71°F). The minimum temperatures in December are also higher at 10°C (50°F), while November experiences a cooler minimum of 7°C (45°F). However, December brings less precipitation overall, with 69 mm (2.7 in) over 8 days, compared to November's 81 mm (3.2 in) over just 6 days. Additionally, humidity levels are lower in December at 51%, compared to November's 56%. For more detailed information on November weather, you can refer to Rosario weather in November.

Compare Rosario's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Rosario

As December unfolds in Rosario, the weather marks a transition to warmer, more vibrant conditions. With maximum temperatures soaring to 38°C (100°F), this month offers a stark contrast to the cooler temperatures of preceding months, creating a perfect backdrop for outdoor activities and festivities. The average temperature hovers around a pleasant 24°C (75°F), while cooler nights with lows of 10°C (50°F) provide a refreshing respite. Though December experiences some rain with about 69 mm (2.7 in) of precipitation over 8 days, the humidity, remaining at a manageable 51%, keeps the air feeling comfortable. This blend of warmth and occasional showers makes December a uniquely inviting time to explore Rosario. For a deeper dive into the weather patterns, check out Rosario Climate.