January Weather in Niteroi, Brazil

Last updated: August 21, 2025

January in Niteroi, Brazil is characterized by warm temperatures and a lush, tropical ambiance. The maximum temperature can reach a sizzling 34°C (94°F), while the average hovers around a comfortable 27°C (81°F), with nightly lows settling at 21°C (70°F). This month sees an average rainfall of 91 mm (3.6 in) over approximately 11 days, contributing to the region's humidity, which sits at a sticky 85%. While the warmth invites outdoor activities, the occasional rain brings a refreshing contrast, enhancing the vibrant greenery typical of this coastal paradise.

January Temperature in Niteroi

In January, Niteroi, Brazil, welcomes summer with warm temperatures that enchant both locals and visitors alike. The month opens with a minimum of 21°C (70°F), while the average climbs to a comfortable 27°C (81°F). As the sun peaks, temperatures can soar to a sizzling 34°C (94°F), crafting ideal conditions for beach-goers and outdoor enthusiasts. This warmth signals the start of a trend that continues into February, where highs reach even 35°C (95°F). January's pleasant nights and vibrant days mark the season's peak, showcasing Niteroi's allure as a tropical paradise, while the gradual cooling in the following months hints at a more temperate climate as autumn approaches.

January Weather in Niteroi: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Niteroi, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Niteroi, January 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).
JanFebMarAprMayJunJulAugSepOctNovDec818080777372717073757578
Data source: Temperature data for Niteroi 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.

January Precipitation in Niteroi

January in Niteroi, Brazil, marks the beginning of the year with moderate rainfall, totaling 91 mm (3.6 in) over approximately 11 days. This precipitation lays the groundwork for a wet season, as January leads into February, which sees a significant increase to 119 mm (4.7 in). The trend continues to peak in March, where the rainfall reaches 138 mm (5.4 in), indicating a typical pattern of increasing precipitation during the summer months. As the year progresses, however, precipitation gradually declines, with April, May, and following months experiencing notably less rainfall. This pattern highlights a seasonal fluctuation, where early summer is marked by heavier rains, giving way to a drier winter period, hence showcasing Niteroi's distinctive tropical climate.

January Precipitation Trends in Niteroi

The chart displays monthly precipitation patterns in Niteroi, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Niteroi, January typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec9111913881733935684886115121
Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.
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January Humidity in Niteroi

In Niteroi, Brazil, January welcomes visitors with a high humidity level of 85%, mirroring February's conditions and hinting at a warm, tropical atmosphere. As summer progresses into March, humidity slightly rises to 86%, creating an even more muggy ambiance. However, this moisture begins to taper off as the year transitions into the cooler months, with April witnessing a slight decrease to 83% and continuing downwards through the year, hitting a low of 61% in October. The trend showcases a gradual decline in humidity as the months shift from the sweltering summer heat to the milder conditions of winter, ultimately providing a refreshing reprieve as the year concludes with a moderate 75% in December. This ebb and flow of humidity not only reflects Niteroi's vibrant climate but also sets the stage for the region's diverse seasonal experiences.

January Average Humidity in Niteroi

This chart illustrates the average monthly humidity levels in Niteroi, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Niteroi is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec85%85%86%83%81%80%76%73%68%61%72%75%
Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Niteroi

In January, the UV Index in Niteroi, Brazil reaches a staggering 15, placing it in the extreme exposure category, which means you can get sunburned in just 10 minutes. This intensity is consistent through February, with only a slight dip to 14 before slowly tapering off in March to 13. As the seasons change, the UV Index begins to lower, dropping to 10 in April, still categorized as very high. By May, the index decreases further to 7, signifying high exposure and allowing for a longer burn time of 25 minutes. This trend continues through the following months, with gradual improvements in UV levels during the winter, yet spikes back up in September through December, showcasing the cyclical nature of ultraviolet radiation in the region. For more detailed insights, check out the Niteroi UV Index.

Maximum UV Index Levels in Niteroi for January

The chart shows the monthly maximum UV Index (UVI) for Niteroi in January, 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 January, the maximum UV index in Niteroi typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec15141310767911121315
Data source: Niteroi January 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.

January Sunshine in Niteroi

In Niteroi, Brazil, January bathes the city in a delightful 270 hours of sunshine, setting a warm tone for the year ahead. This radiant start is closely matched by February, which offers just a touch more at 271 hours. As summer continues, March shines brightly with 309 hours, marking its peak, before April sees a slight dip to 296 hours. The sunny days persist through May and June, maintaining a pleasant average of around 280 hours. July and August enjoy a revival, both showcasing 290 and 275 hours respectively, as the golden hues of late winter wrap the city. With September returning to a sunnier 293 hours and October following suit with 281 hours, residents relish the consistency of sunlight. The year rounds out with November’s 284 hours, culminating in December’s dazzling 318 hours, making it the sunniest month of all. This pattern highlights a vibrant yearly cycle, emphasizing Niteroi's charm and appeal under the warm Brazilian sun.

Monthly Sunshine Duration in Niteroi: January Highlighted

The January sunshine duration represents the total number of hours Niteroi experiences direct sunlight during the month of January, excluding cloudy or obstructed periods. This chart compares the sunshine duration of January with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec270h271h309h296h282h276h290h275h293h281h284h318h
Data source: Niteroi January Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Niteroi During January

In Niteroi, Brazil, the likelihood of sunny weather in January stands at 36%, making it a relatively modest start to the year. This percentage is slightly higher than the previous month, February, which drops to 33%, hinting at a potential trend where sunshine becomes more elusive as the year begins. However, as we move into the following months, the sun seems to reclaim its dominance, with the likelihood of sunny days peaking at 58% in July and 60% in August. Notably, the shift towards clearer skies continues through the latter half of the year, while the chances drop sharply to just 20% in October. This pattern illustrates that while January may be a bit cloudy, the months ahead tend to brighten up significantly, making for a sunnier and more enjoyable climate as the year progresses.

Percentage of Sunny Days in January in Niteroi

The chart illustrates the percentage of sunny days in Niteroi throughout the year, with January 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 Niteroi experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec36%33%51%55%49%54%58%60%50%20%37%42%
Data source: Niteroi January chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Niteroi in January

In Niteroi, Brazil, January shines brightest with an impressive 13 hours of daylight, setting the tone for the vibrant summer season. As the year progresses into February and March, daylight remains ample at 12 hours, perfect for outdoor adventures. However, by April, there's a gentle decline, with daylight tapering to 11 hours, and continuing to decrease to a steady 10 hours through the winter months of June and July. As spring emerges in August, daylight begins its gradual ascent again, climbing back to 11 hours by late summer. The cycle continues, reaching a peak once more at 13 hours in both November and December, showcasing Niteroi's beautiful rhythm of light throughout the year. This dynamic interplay of daylight not only reflects the changing seasons but also enriches the daily lives of its residents and visitors.

Average Daylight Hours in Niteroi for January

The chart illustrates the variation in daylight duration in Niteroi throughout the year, with January highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec13h 20m12h 50m12h 11m11h 31m10h 59m10h 44m10h 52m11h 20m11h 57m12h 37m13h 12m13h 30m
Data source: Niteroi daylight hours, calculated by summing the hours between sunrise and sunset for each day.

January Winds in Niteroi

In Niteroi, Brazil, January ushers in a gentle breeze with an average wind speed of 3.4 m/s (8 mph), offering a soothing start to the year. This consistent wind pattern maintains its vigor into April, matching January's pace, before a slight decline occurs over the next few months. As the year progresses into the latter half, we witness a gradual increase in wind speed, peaking at 4.2 m/s (9 mph) in October. This trend indicates that as the seasons shift, so does the strength of Niteroi's winds, creating a dynamic atmosphere that enhances the city’s coastal charm. From the tranquil beginnings of January to the more robust breezes of October, the varying wind speeds reflect the vibrant rhythm of Niteroi's climate.

Average January Wind Speed in Niteroi

The chart displays monthly wind speed patterns in Niteroi, with values for each month shown alongside January's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how January's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.4 m/s2.32.53.42.43.13.13.74.04.23.33.0
Data source: Niteroi January wind data, generated using information from the Copernicus Climate Change Service.

How January Weather in Niteroi Compares to Other Months

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

In comparing January and February weather, both months exhibit a warm climate with minimal variations in temperature. January sees minimum temperatures of 21°C (70°F) and a maximum of 34°C (94°F), with an average temperature of 27°C (81°F). In contrast, February experiences a slightly higher maximum temperature of 35°C (95°F), while the average remains consistent at 27°C (80°F). Precipitation is more pronounced in February, with 119 mm (4.7 in) over 15 days, compared to January's 91 mm (3.6 in) across 11 days. Humidity levels remain steady at 85% for both months, contributing to the overall tropical feel. For more detailed information, check out Niteroi weather in February.

In January, the weather features a warm average temperature of 27°C (81°F) and occasional highs reaching up to 34°C (94°F). The month sees about 91 mm (3.6 in) of precipitation over 11 days, accompanied by high humidity levels at 85%. In contrast, March maintains a similar average temperature but experiences slightly cooler minimums at 20°C (69°F) and can also reach 34°C (94°F). However, it is significantly wetter, with 138 mm (5.4 in) of rain spread across 16 days and a humidity rate of 86%. For a detailed look at Niteroi's weather in March, you can visit Niteroi weather in March.

In comparing January and April weather, both months exhibit warm temperatures, with January having a slightly higher average of 27°C (81°F) compared to April's 25°C (77°F). January experiences minimum temperatures around 21°C (70°F) and highs reaching 34°C (94°F), similar to April's range of 19°C (67°F) to 34°C (93°F). Precipitation is relatively close, with January receiving 91 mm (3.6 in) over 11 days, while April has a bit less at 81 mm (3.2 in) across 14 days. Humidity levels are also comparable, at 85% in January versus 83% in April. For a detailed look at what to expect, visit Niteroi weather in April.

In January, the weather is characterized by higher temperatures, with minimums around 21°C (70°F) and maximums reaching up to 34°C (94°F), averaging 27°C (81°F). This month also sees considerable humidity at 85% and a total precipitation of 91 mm (3.6 in) over 11 days. In contrast, May experiences milder conditions, with minimum temperatures dropping to 16°C (61°F), an average of 23°C (74°F), and maximums slightly lower at 33°C (91°F). Precipitation decreases to 73 mm (2.9 in) across 10 days, with humidity also slightly reduced at 81%. For more specific information about May weather, you can check Niteroi weather in May.

In January, the weather is typically warmer, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 34°C (94°F), and an average temperature of 27°C (81°F). The month experiences higher humidity at 85% and substantial rainfall, with 91 mm (3.6 in) of precipitation over 11 days. In contrast, June sees cooler temperatures, with a minimum of 16°C (62°F) and a maximum of 31°C (89°F), averaging at 22°C (73°F). The humidity decreases to 80%, and rainfall is lighter, totaling 39 mm (1.5 in) over 9 days. For more details, you can check Niteroi weather in June.

January and July present contrasting weather conditions in Niteroi. In January, temperatures range from a minimum of 21°C (70°F) to a maximum of 34°C (94°F), with an average of 27°C (81°F). The month sees substantial precipitation, totaling 91 mm (3.6 in) over 11 days, accompanied by high humidity levels at 85%. In contrast, July experiences cooler temperatures, with a minimum of 15°C (59°F) and a maximum of 32°C (90°F), averaging 21°C (71°F). Precipitation drops significantly to 35 mm (1.4 in) over just 6 days, and humidity levels also decrease to 76%. For more detailed information on July weather, you can visit Niteroi weather in July.

In January, the weather in Niteroi is notably warmer, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 34°C (94°F), and an average of 27°C (81°F). This month sees a higher level of humidity at 85%, contributing to a more tropical feel, along with 91 mm (3.6 in) of precipitation over 11 days. In contrast, August experiences cooler temperatures, with a minimum of 14°C (58°F), an average of 21°C (71°F), and a maximum of 32°C (90°F). The humidity drops to 73%, and there is less rain, totaling 68 mm (2.7 in), also spread over 11 days. For more details on the weather, check out Niteroi weather in August.

In January, the weather is typically warmer, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 34°C (94°F), and an average of 27°C (81°F). The month also sees high humidity at 85% and substantial rainfall, accumulating 91 mm (3.6 in) over about 11 days. In contrast, September experiences milder temperatures, with a minimum of 17°C (63°F) and the same maximum of 34°C (94°F), but an average temperature of only 23°C (74°F). Precipitation decreases significantly to 48 mm (1.9 in) over 8 days, and humidity drops to 68%. For a closer look at September's climate, you can visit Niteroi weather in September.

In January, the weather is characterized by warm temperatures, with a minimum of 21°C (70°F) and an average of 27°C (81°F), reaching a maximum of 34°C (94°F). This month also experiences higher humidity levels at 85% and significant rainfall, averaging 91 mm (3.6 in) over 11 days. In contrast, October sees slightly cooler temperatures, with a minimum of 17°C (63°F) and an average of 24°C (75°F), peaking at 36°C (97°F). Precipitation is slightly lower at 86 mm (3.4 in), but it occurs over more days, totaling 14. Additionally, October enjoys considerably lower humidity levels at 61%. For more details, check out the Niteroi weather in October.

January and November showcase distinct weather patterns, with January generally being warmer and more humid. In January, temperatures range from a minimum of 21°C (70°F) to a maximum of 34°C (94°F), with an average temperature of 27°C (81°F). The month also experiences higher humidity at 85% and sees about 91 mm (3.6 in) of precipitation over 11 days. In contrast, November features cooler temperatures, with a minimum of 18°C (64°F) and an average of 24°C (75°F), though it can still reach up to 34°C (94°F). Rainfall is more frequent in November, totaling 115 mm (4.5 in) over 16 days, but the humidity is lower at 72%. For more details on November weather, you can refer to Niteroi weather in November.

In comparing the weather between January and December, January tends to be slightly warmer with average temperatures reaching up to 27°C (81°F), while December averages at a cooler 25°C (78°F). January also sees higher maximum temperatures, peaking at 34°C (94°F) compared to December's 33°C (92°F). However, December experiences more precipitation, with 121 mm (4.8 in) over 15 days, while January receives 91 mm (3.6 in) across 11 days. Additionally, January is more humid, with 85% humidity compared to December's 75%. For more details on December's weather, you can check Niteroi weather in December.

Compare Niteroi's Climate with Cities Worldwide

Conclusion: What to Expect From January Weather in Niteroi

January in Niteroi stands out with its warm and humid climate, making it distinctly different from other months of the year. With temperatures reaching a sweltering maximum of 34°C (94°F), this month brings a vibrant energy, perfect for beach outings and outdoor activities. Though occasional rain may dampen the mood on about 11 days, the overall atmosphere remains lively with an average temperature of 27°C (81°F). The high humidity can be quite palpable, enhancing that tropical feel. Visitors can enjoy the sun while still preparing for the brief rain showers typical of summer. For more insights into what to expect throughout the year, check out the Niteroi Climate.