May Weather in Porto Alegre, Brazil

Last updated: August 21, 2025

May in Porto Alegre, Brazil brings a delightful mix of mild temperatures and occasional rainfall. With maximum temperatures reaching 32°C (90°F) and dipping to a refreshing 5°C (41°F) at night, the average settles around a comfortable 17°C (63°F). This month typically sees about 153 mm (6.0 in) of precipitation spread over approximately 10 days, contributing to an overall humidity level of 87%. Whether you're looking to explore the city or simply enjoy the transitional weather, May offers a vibrant backdrop for experiencing Porto Alegre's natural beauty.

May Temperature in Porto Alegre

In May, Porto Alegre experiences a notable transition in temperatures, signaling the arrival of autumn. The minimum temperature drops to 5°C (41°F), inviting cooler days ahead. Daytime warmth remains pleasant, with an average of 17°C (63°F) and a maximum reaching 32°C (90°F). This month marks a distinct cooling trend from the sweltering summer, as temperatures dip from the highs observed in April, creating a more temperate climate. The general decline in temperatures not only hints at the forthcoming winter but also enhances the city's charm, as the lush landscapes become even more inviting for outdoor activities. This blend of cooler mornings and warm afternoons makes May a delightful time to experience the beauty of Porto Alegre.

May Weather in Porto Alegre: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Porto Alegre, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Porto Alegre, May 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).
JanFebMarAprMayJunJulAugSepOctNovDec787774706360586065687175
Data source: Temperature data for Porto Alegre 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.

May Precipitation in Porto Alegre

May in Porto Alegre marks a significant uptick in precipitation, with an average of 153 mm (6.0 in) across 10 days of rain. This makes May one of the wettest months of the year, clearly surpassing the preceding months, where April saw just 73 mm (2.9 in). The trend continues into June, but May stands out as a pivotal time when the city transitions into a wetter season, setting the stage for heavier rains seen in the latter part of the year. As the rain nourishes the vibrant landscapes, it reflects a shift in the climate rhythm of Porto Alegre, fostering growth and maintaining the lush scenery the region is known for.

May Precipitation Trends in Porto Alegre

The chart displays monthly precipitation patterns in Porto Alegre, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Porto Alegre, May typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec93112109731531131237015513911280
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Porto Alegre

In May, Porto Alegre experiences a notable increase in humidity, reaching 87%, which is the highest level of the year. This surge reflects a broader trend observed from April, where humidity levels consistently rise, peaking before a slight decline in the following months. The escalating moisture in the air hints at the transition into the winter season, positioning May as a pivotal month that bridges the more humid summer months and the slightly drier winter ones. As residents prepare for the cooler temperatures, the increased humidity adds a heavy, atmospheric quality to the city, contributing to a unique characteristic of Porto Alegre's late autumn.

May Average Humidity in Porto Alegre

This chart illustrates the average monthly humidity levels in Porto Alegre, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Porto Alegre is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec78%79%79%82%87%85%82%81%84%85%82%84%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Porto Alegre

In May, Porto Alegre experiences a notable shift in its UV Index, decreasing to 6—a level categorized as high. This signifies a transition from the intense extremes witnessed in the earlier months of the year, where indices soared up to 14 in January, prompting a burn time of merely 10 minutes. With longer burn times of 25 minutes in May, residents can enjoy the outdoors with a bit more leeway, although caution is still advised. As winter approaches, the UV Index continues to decrease, hinting at the seasonal changes inherent in this southern Brazilian city. For more detailed information about UV levels throughout the year, visit Porto Alegre UV Index.

Maximum UV Index Levels in Porto Alegre for May

The chart shows the monthly maximum UV Index (UVI) for Porto Alegre in May, 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 May, the maximum UV index in Porto Alegre typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec141312964579121314
Data source: Porto Alegre May 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.

May Sunshine in Porto Alegre

As May beckons in Porto Alegre, the city experiences a transition from the sunlit exuberance of the previous months, with a total of 230 hours of sunshine this month. While May sees a dip in sunshine compared to the vibrant January, February, and March, each boasting over 300 hours, it still radiates a warmth that heralds the onset of winter. Following the vibrant golden glow of November and the dazzling December with their remarkable 316 and 361 hours respectively, May’s sunlit days provide a gentle reminder that though the days grow shorter, the beauty of Porto Alegre remains vivid. As households and cafes begin to shift from the warm glow of spring to the cozy ambiance of winter, the city still enjoys a respectable share of sunny days, trailing closely behind April's 271 hours, indicating the stunning interplay of light and warmth that characterizes this charming Brazilian city.

Monthly Sunshine Duration in Porto Alegre: May Highlighted

The May sunshine duration represents the total number of hours Porto Alegre experiences direct sunlight during the month of May, excluding cloudy or obstructed periods. This chart compares the sunshine duration of May with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec272h310h312h271h230h220h239h257h228h274h316h361h
Data source: Porto Alegre May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Porto Alegre During May

In Porto Alegre, Brazil, May offers a promising 55% chance of sunny weather, making it one of the more favorable months for sunshine as the year unfolds. This slight uptick follows the sunnier April at 54%, showcasing a satisfying transition into late autumn. Interestingly, while the chance of sun dips in June to 32%, May stands out as a bright spot in a generally varied climatic landscape. As temperatures cool down from the summer months, the likelihood of sunshine mirrors an upward trend that peaks again in July with 60% sunshine probability. Thus, May presents an excellent opportunity to enjoy the outdoors before winter's chill sets in, ensuring a delightful experience in Porto Alegre's temperate climate.

Percentage of Sunny Days in May in Porto Alegre

The chart illustrates the percentage of sunny days in Porto Alegre throughout the year, with May 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 Porto Alegre experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec43%59%40%54%55%32%61%40%30%48%52%57%
Data source: Porto Alegre May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Porto Alegre in May

In Porto Alegre, Brazil, the duration of daylight exhibits a clear seasonal rhythm, beginning with an ample 13 hours in both January and February, gradually decreasing as the months progress. By May, the city experiences a noticeable drop to 10 hours, a trend that persists into June and July. However, as winter gives way to spring, daylight begins to incrementally increase, with an uplifting return to 11 hours in August and September. The cycle culminates in December with the longest daylight of the year at 14 hours, showcasing the vibrant contrast between the sunlit days of summer and the shorter, cozy winter hours. This ebb and flow of daylight not only marks the changing seasons but also shapes the lifestyle and activities of Porto Alegre's residents throughout the year.

Average Daylight Hours in Porto Alegre for May

The chart illustrates the variation in daylight duration in Porto Alegre throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec13h 48m13h 6m12h 13m11h 19m10h 35m10h 14m10h 25m11h 4m11h 55m12h 49m13h 36m14h 1m
Data source: Porto Alegre daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Porto Alegre

In May, Porto Alegre experiences a gentle breeze with an average wind speed of 2.7 m/s (approximately 6 mph), mirroring the calmer conditions of April. This slight stability in wind patterns marks a transitional phase as the city prepares for the more vigorous gusts of June and July, which tend to reach an average of 3.2 m/s (7 mph) and 2.8 m/s (6 mph), respectively. Interestingly, May's mild winds contribute to a comfortable atmosphere, encouraging residents and visitors to enjoy the outdoors before the chill of winter settles in. As the year progresses, September and October present a resurgence in wind activity, suggesting a dynamic shift that heralds the changing seasons.

Average May Wind Speed in Porto Alegre

The chart displays monthly wind speed patterns in Porto Alegre, with values for each month shown alongside May's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how May's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.12.92.62.72.7 m/s3.22.82.93.33.33.43.7
Data source: Porto Alegre May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Porto Alegre Compares to Other Months

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

In May, temperatures in Porto Alegre range from a minimum of 5°C (41°F) to a maximum of 32°C (90°F), with an average of 17°C (63°F). This month experiences significant precipitation, totaling 153 mm (6.0 in) over approximately 10 days, along with high humidity levels at 87%. In contrast, January brings warmer temperatures, with a minimum of 15°C (58°F) and a maximum reaching 39°C (103°F), along with an average of 26°C (79°F). Although it has slightly less rainfall at 93 mm (3.7 in) over about 12 days, the humidity is lower at 77%. For more detailed information, check out Porto Alegre weather in January.

When comparing the weather in May and February, we can see notable differences in temperature and humidity. May experiences a wider temperature range, with minimums reaching 5°C (41°F) and maximums soaring to 32°C (90°F), while February consistently stays warmer, with minimums of 14°C (58°F) and maximums peaking at 38°C (100°F). Additionally, February has a higher average temperature of 25°C (77°F) compared to May's average of 17°C (63°F). While precipitation levels are relatively close, May has slightly more rain at 153 mm (6.0 in) over 10 days, in contrast to February's 112 mm (4.4 in) over 11 days. Humidity levels are higher in May at 87%, compared to February's 79%, indicating a more muggy atmosphere during the earlier month. For more detailed information on the February climate, you can visit Porto Alegre weather in February.

In comparing the weather between May and March, we can see significant differences in temperature and precipitation patterns. March features a wider temperature range, with minimums at 13°C (56°F) and maximums peaking at an impressive 38°C (100°F), while May has milder temperatures, fluctuating from a minimum of 5°C (41°F) to a maximum of 32°C (90°F). Despite March being typically hotter, it experiences slightly less precipitation than May, with 109 mm (4.3 in) over 12 days, compared to May's 153 mm (6.0 in) over 10 days. Additionally, humidity levels are higher in May at 87%, compared to March's 79%, contributing to a more muggy feel in late spring. For a more detailed look at March weather specifics, check out Porto Alegre weather in March.

In comparing the weather of April and May, we observe notable differences in temperature and precipitation. April experiences a slightly higher minimum temperature of 8°C (47°F) and an average of 21°C (71°F), reaching a maximum of 34°C (93°F). Conversely, May sees cooler temperatures, with a minimum of 5°C (41°F) and an average of 17°C (63°F), peaking at 32°C (90°F). Additionally, May is characterized by substantially higher precipitation, totaling 153 mm (6.0 in) over 10 days, compared to April's 73 mm (2.9 in) over 8 days. The humidity remains relatively high in both months, with May at 87% and April at 82%. For more insights, you can check Porto Alegre weather in April.

In comparing the weather of May and June, we observe that May tends to be slightly warmer overall, with average temperatures reaching 17°C (63°F) compared to June's 16°C (60°F). Both months experience comfortable highs, with May peaking at 32°C (90°F) and June slightly lower at 31°C (88°F). However, June sees a slightly cooler minimum temperature of 3°C (38°F) compared to May's 5°C (41°F). Precipitation decreases from 153 mm (6.0 in) in May to 113 mm (4.4 in) in June, along with a minor reduction in the number of rainy days, from 10 days in May to 9 days in June. Humidity remains relatively consistent in both months, at 87% for May and 85% for June. For more detailed insights, check out Porto Alegre weather in June.

In May, the weather in Porto Alegre is characterized by a wider temperature range, with minimums of 5°C (41°F) and maximums reaching up to 32°C (90°F), resulting in an average of 17°C (63°F). The month sees considerable precipitation, with 153 mm (6.0 in) over 10 days and a high humidity level of 87%. In contrast, July experiences cooler temperatures, with a minimum of 2°C (35°F) and an average of 14°C (58°F), peaking at 30°C (87°F). Rainfall decreases to 122 mm (4.8 in) over just 8 days, accompanied by slightly lower humidity at 82%. For a more detailed look at the weather patterns in July, you can refer to Porto Alegre weather in July.

May and August showcase distinct weather patterns. In May, the temperatures range from a minimum of 5°C (41°F) to a maximum of 32°C (90°F), with an average of 17°C (63°F). This month experiences higher precipitation with 153 mm (6.0 in) over approximately 10 days and a humidity level of 87%. In contrast, August sees slightly cooler temperatures, with a minimum of 3°C (38°F) and a maximum of 34°C (94°F), averaging 16°C (61°F). Precipitation drops significantly to 70 mm (2.8 in) over about 8 days, accompanied by lower humidity at 81%. For a more detailed look at the weather in August, you can check Porto Alegre weather in August.

May and September both showcase relatively mild temperatures, but there are notable differences in their weather patterns. In May, temperatures range from a minimum of 5°C (41°F) to a maximum of 32°C (90°F), with an average of 17°C (63°F). The month experiences significant precipitation, totaling 153 mm (6.0 in) over about 10 days, and high humidity levels at 87%. Conversely, September sees slightly warmer conditions with minimums of 7°C (45°F) and maximums reaching up to 36°C (96°F), while the average temperature sits at 18°C (65°F). Precipitation in September is similar, at 155 mm (6.1 in), but it occurs over 12 days, and humidity is marginally lower at 84%. For a detailed insight into September weather, visit Porto Alegre weather in September.

May and October in Porto Alegre exhibit distinct weather patterns that reflect the transition between seasons. In May, temperatures range from a minimum of 5°C (41°F) to a maximum of 32°C (90°F), with an average of 17°C (63°F). This month also sees significant precipitation, totaling 153 mm (6.0 in) over about 10 days, combined with high humidity at 87%.

In contrast, October offers slightly milder temperatures, with a minimum of 9°C (49°F) and a maximum reaching 37°C (100°F), averaging at 20°C (68°F). The precipitation in October is slightly lower at 139 mm (5.5 in) over 13 days, and humidity drops slightly to 85%. For a detailed look at the weather during October in Porto Alegre, you can check out Porto Alegre weather in October.

In comparing the weather of May and November, notable differences emerge in both temperature and humidity. May experiences a wider range of temperatures, with a minimum of 5°C (41°F) and a maximum of 32°C (90°F), averaging around 17°C (63°F). In contrast, November sees consistently warmer conditions, with minimums at 12°C (53°F) and maximums reaching 37°C (99°F), averaging 22°C (72°F). While May has a higher humidity level at 87%, November is slightly lower at 82%. Additionally, May receives more precipitation, totaling 153 mm (6.0 in) over 10 days, compared to November’s 112 mm (4.4 in) over the same duration. For more information on November's weather specifics, you can check Porto Alegre weather in November.

In May, the weather tends to vary significantly, with temperatures ranging from a chilly 5°C (41°F) at night to a warm 32°C (90°F) during the day, averaging around 17°C (63°F). This month experiences considerable rainfall, with 153 mm (6.0 in) over approximately 10 days and a high humidity of 87%. In contrast, December brings a more consistent warmth, with nighttime lows of 13°C (55°F) and daytime highs reaching up to 38°C (101°F), averaging 24°C (76°F). Precipitation is lighter in this month, totaling 80 mm (3.2 in) over about 8 days and a slightly lower humidity of 84%. For a detailed look at December weather, check out Porto Alegre weather in December.

Compare Porto Alegre's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Porto Alegre

As May arrives in Porto Alegre, the weather undergoes a noticeable transformation. The warm days can peak at a maximum of 32°C (90°F), but the average temperature settles around a comfortable 17°C (63°F). In contrast to the preceding months, there is an increase in precipitation, with about 153 mm (6.0 in) falling over roughly 10 days, contributing to a humidity level of 87%. This combination of warmth and moisture provides a distinct feel to the month, making it a transitional period as the city shifts towards winter. For more detailed insights on how May compares to other months, visit Porto Alegre Climate.