Last updated: August 21, 2025
December in São Luís, Brazil brings warm and tropical weather, with maximum temperatures reaching 30°C (87°F) and an average of 27°C (82°F). This month also sees minimum temperatures around 24°C (75°F), creating a comfortable climate for outdoor activities. However, visitors should prepare for frequent rainfall, with 117 mm (4.6 in) of precipitation spread over approximately 23 days, resulting in a humidity level of 78%. Despite the rain, the region's vibrant culture and stunning landscapes make December a captivating time to explore this coastal gem.
In December, São Luís, Brazil experiences consistently warm temperatures, typical of its tropical climate. The month begins with a pleasant average temperature of 27°C (82°F), where the minimum dips slightly to 24°C (75°F) and peaks at a comfortable 30°C (87°F). This trend reflects the stability of the region's weather pattern, with maximum temperatures hovering around the 30°C mark throughout late spring. As the year winds down, December's warmth is a continuation of elevated temperatures observed since April, creating an inviting atmosphere perfect for enjoying the city's stunning beaches and vibrant culture.
In December, São Luís experiences a notable shift in its precipitation pattern, with 117 mm (4.6 in) of rainfall spread over approximately 23 days. This marks a transition from the heavy downpours of earlier months like February and March, which frequently exceed 400 mm, to a more moderate wet season. Interestingly, while December sees a significant amount of rain, it is a part of a gradual decrease in both precipitation and rainy days that starts in mid-year—July's low of just 4.2 in (107 mm) highlights this decline. As the city braces for the peak of the wet season, December's consistent showers hint at the lush tropical landscape that awaits in the coming months, providing both challenges and beauty to the vibrant city.
In Sao Luis, Brazil, December marks a noticeable shift in humidity levels, with an average of 78%. As the year progresses, we observe a gradual decline in humidity from the peak of 92% in April, reaching its lowest point in August at 55%. Following this dry spell, the humidity begins to rise again, culminating in the December figures which provide a refreshing yet humid atmosphere as summer approaches. This fluctuation signals the transition towards a more humid rainy season, characteristic of Sao Luis's tropical climate, where the air feels heavier as the month draws to a close.
In December, the UV Index in Sao Luis, Brazil remains at a significant level of 13, categorized as extreme, where just 10 minutes of exposure can lead to skin damage. This month shares the same UV rating as the preceding November, maintaining a trend of consistently high levels that have persisted throughout the year. From January to March, the UV Index peaks at 16, while the values gradually decline to 12 in June and further slip to 11 in July. However, even as we reach December, protective measures are essential due to the persistent extreme exposure, underscoring the importance of sun safety year-round. For more information on the UV Index in this vibrant city, visit Sao Luis UV Index.
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As December arrives in Sao Luis, Brazil, residents and visitors alike are greeted with a spectacular 317 hours of sunshine, a fitting close to the year. The trend through the months reveals a gradual increase in sunlight, peaking during the heart of winter with July and August basking in over 340 hours each. This upward trajectory in sunshine is indicative of Sao Luis's tropical climate, making it an ideal destination for those seeking warmth and light. Interestingly, the city experiences a slight dip in sunlight hours in April and November, yet it consistently stays above 300 hours during the peak months from May to October. As such, December strikes a perfect balance of brightness, inviting all to enjoy the lingering rays of the sun before the new year begins.
In Sao Luis, Brazil, the likelihood of sunny weather sees a notable shift as the year progresses. December marks a transitional phase, with a 28% chance of sunshine, following the decreasing trend from the previous months. This is a dip from November's 45%, indicating a shift towards the summer season when rainfall begins to increase. As the year unfolds, sunny days become more prominent between June and August, boasting probabilities upwards of 51% to 66%, suggesting that while December might not offer the most reliable sunshine, it gracefully sets the stage for the vibrant, sunnier months ahead.
In São Luís, Brazil, daylight duration exhibits a remarkable consistency throughout the year, with most months enjoying around 12 hours of sunlight. From January through April, the days remain evenly illuminated at this ideal length, fostering a vibrant atmosphere. As the year progresses into May, a slight decrease to 11 hours is observed, signaling the onset of the winter months. This reduction persists through July, after which the days gradually return to the 12-hour mark starting in August. Remarkably, December echoes the early months, again basking in 12 hours of daylight, ensuring that the city is beautifully lit, especially during the festive season. Overall, São Luís boasts a climate where sunlight is abundant and relatively stable, enhancing its allure year-round.
As December rolls into São Luís, Brazil, the coastal winds pick up slightly, with an average speed of 5.5 m/s (12 mph). This marks a refreshing change after the lower speeds seen in the preceding months, particularly May, which recorded a calm 3.3 m/s (7 mph). The trend reveals a gradual increase in wind intensity from August through October, peaking in September at 6.0 m/s (13 mph). December's breezy air invites residents and visitors alike to embrace the vibrant outdoor life. As the year winds down, the invigorating gusts hint at the approach of summer, promising both comfort and adventure along the beautiful shores of São Luís.
Weather in Sao Luis varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Sao Luis, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, the weather in São Luís presents a warm climate with temperatures ranging from a minimum of 24°C (75°F) to a maximum of 30°C (87°F) and an average of 27°C (82°F). The month also experiences significant rainfall, with 117 mm (4.6 in) spread over 23 days and a humidity level of 78%. In contrast, January sees a slight decrease in maximum temperature, peaking at 29°C (85°F), while maintaining a similar average of 27°C (80°F) and the same minimum. However, January is marked by increased precipitation, totaling 217 mm (8.5 in) over 25 days and rising humidity levels at 89%. For more details on January's climate, you can check Sao Luis weather in January.
December and February offer distinct weather experiences, with both months characterized by warm temperatures but differing levels of precipitation and humidity. In December, temperatures range from a minimum of 24°C (75°F) to a maximum of 30°C (87°F), averaging around 27°C (82°F) with 117 mm (4.6 in) of rainfall spread over 23 days and humidity at 78%. In contrast, February features slightly cooler temperatures, with a minimum of 23°C (74°F) and a maximum of 29°C (85°F), averaging 26°C (80°F). However, it sees a dramatic increase in rainfall, reaching 427 mm (16.8 in) over 27 days and higher humidity levels at 90%. For more details, you can check Sao Luis weather in February.
When comparing the weather in December and March, December tends to be slightly warmer with average temperatures ranging from a minimum of 24°C (75°F) to a maximum of 30°C (87°F), while March has a marginally cooler average temperature of 26°C (80°F). However, March experiences significantly increased precipitation, accumulating 483 mm (19.0 in) over 30 days compared to December's 117 mm (4.6 in) across 23 days. Additionally, the humidity level rises from 78% in December to 90% in March, contributing to a more tropical feel during the latter month. For more detailed insights, you can check out Sao Luis weather in March.
In December, the weather in Sao Luis features temperatures ranging from a minimum of 24°C (75°F) to a maximum of 30°C (87°F), with an average temperature of 27°C (82°F). The month experiences about 117 mm (4.6 in) of rainfall over approximately 23 days, making for a humid atmosphere at 78%.
Conversely, April sees similar temperature ranges, with a minimum of 24°C (76°F), an average of 27°C (80°F), and a maximum of 30°C (86°F). However, the precipitation significantly increases to 469 mm (18.5 in), spread across 29 days, leading to a much higher humidity level of 92%. This substantial difference in rainfall highlights the transition from December to April in terms of weather conditions. For more detailed information, check out Sao Luis weather in April.
In both December and May, temperatures remain fairly consistent, with minimums around 24°C (75°F), average temperatures at approximately 27°C (81°F), and maximums reaching 30°C (87°F). However, May experiences significantly higher precipitation, totaling 298 mm (11.7 in) over 27 days compared to December's 117 mm (4.6 in) across 23 days, resulting in increased humidity levels of 89% in May versus 78% in December. This contrast makes May noticeably wetter and more humid than December, impacting outdoor activities. For more details on the weather patterns in May, check Sao Luis weather in May.
December and June in São Luís exhibit strikingly similar temperatures, with both months featuring minimums around 24°C (75°F) and average highs hovering near 30°C (87°F). However, June is slightly warmer on average, with a maximum temperature of 31°C (87°F). When it comes to precipitation, June sees an increase, with 161 mm (6.4 in) of rain over 26 days, compared to December's 117 mm (4.6 in) over 23 days. Both months boast high humidity levels, with December at 78% and June just a notch higher at 79%. For more details on June weather patterns, check out Sao Luis weather in June.
In December, the weather remains warm, with temperatures ranging from a minimum of 24°C (75°F) to a maximum of 30°C (87°F), and an average of 27°C (82°F). The month experiences 117 mm (4.6 in) of precipitation over 23 days, contributing to a high humidity level of 78%. In contrast, July offers slightly hotter conditions, with maximum temperatures reaching up to 31°C (89°F) while maintaining a similar minimum of 24°C (75°F) and an average of 27°C (81°F). Precipitation in July is a bit lower at 107 mm (4.2 in) over 22 days, and humidity drops to a more comfortable 64%. For more details, you can check Sao Luis weather in July.
December and August in São Luís showcase distinct weather patterns, despite having similar average temperatures. In December, the temperature ranges from a minimum of 24°C (75°F) to a maximum of 30°C (87°F), accompanied by significant precipitation of 117 mm (4.6 in) over 23 days, resulting in a higher humidity level of 78%. In contrast, August sees slightly warmer peak temperatures up to 31°C (88°F), but with much less rainfall of only 37 mm (1.5 in) over just 11 days, contributing to lower humidity at 55%. For a closer look at São Luís weather during August, you can visit Sao Luis weather in August.
In December, the weather tends to be warmer and wetter than in September. While both months have an average temperature of 27°C (82°F), December experiences higher minimum and maximum temperatures, ranging from 24°C (75°F) to 30°C (87°F). Additionally, December sees significantly more rainfall, with 117 mm (4.6 in) of precipitation over 23 days, compared to just 21 mm (0.8 in) over 5 days in September. The humidity also rises in December to 78%, while September enjoys a much lower level at 51%. For more detailed information, you can check out Sao Luis weather in September.
In December, the weather in Sao Luis is characterized by slightly lower minimum temperatures, averaging around 24°C (75°F), whereas October's minimum temperature is a bit higher at 25°C (78°F). Both months maintain an average high of 30°C (87°F), but December significantly increases in precipitation, receiving 117 mm (4.6 in) over 23 days compared to just 29 mm (1.1 in) over 8 days in October. Additionally, December's humidity sits at 78%, considerably higher than October's 53%, contributing to a more humid and wet environment. For more details, you can visit Sao Luis weather in October.
Comparing the weather in December and November reveals some notable differences. December experiences slightly cooler temperatures, with a minimum of 24°C (75°F) compared to November's 25°C (77°F), although the average temperature remains the same at 28°C (82°F). Precipitation significantly increases in December, totaling 117 mm (4.6 in) over 23 days, while November has a more manageable 73 mm (2.9 in) across just 12 days. Additionally, humidity rises to 78% in December from 60% in November, contributing to a more tropical feel. For a detailed look at November's weather, you can check this link: Sao Luis weather in November.
As December rolls into Sao Luis, the weather takes on a more tropical character, with higher humidity levels making the air feel warm and sultry. Unlike the drier months earlier in the year, December is marked by increased rainfall, with frequent showers that bring life to the vibrant surroundings. The temperatures remain pleasantly warm, providing a perfect backdrop for exploring the city's rich culture. Whether you're wandering through its historic streets or enjoying the coastal scenery, December offers a unique charm that stands apart from the rest of the year. For a deeper understanding of what to expect throughout the seasons, check out the detailed insights at Sao Luis Climate.