Climate and monthly weather forecast
Niterói, Brazil

Located in Brazil, Niterói enjoys a tropical wet and dry climate, better known by its Köppen climate classification as Aw. This predominate climate in Niterói features two distinct seasons: a wet season and a dry one.

Over the course of the calendar year, temperatures fluctuate mildly in Niterói. The sea temperature ranges from 21.6°C (70.9°F) in September to 25.8°C (78.4°F) in March. Daily daylight hours see a similar trend, with the shortest day in June at 10.7 hours of daylight, and the longest day in December boasting 13.5 hours of daylight.

An interesting pattern in Niterói's climate is a reverse correlation between sea temperature and daylight hours. While sea temperature peaks in early autumn, daylight hours reach the longest duration at the onset of summer. This noteworthy feature establishes a distinctive climate rhythm for Niterói.

Due to its tropical climate, visiting Niterói can be enjoyable all year round. However, for travellers who prefer balmy sea temperatures, the period from January to March, when the sea temperature stays above 25°C (77°F), makes for the most comfortable swimming experience. Accompanied by an average of over 12 hours of daylight, these months offer the perfect conditions for beach-oriented activities, from sunbathing to surfing.

In contrast, the months with the lowest sea temperatures, from July to October when the temperature drops below 23°C (73.4°F), might not be as inviting for water-based activities. Despite this, there's still an average of 11 hours of daylight, allowing ample time to explore Niterói's local attractions and vibrant culture.

Spring in Niterói spans from September to November. This season witnesses a gradual increase in sea temperature, transitioning from 21.6°C (70.9°F) in September to 23.2°C (73.8°F) in November. Correspondingly, daylight hours extend from 12 hours in September to 13.2 hours in November. Despite a chillier sea, the growing daylight hours provide a delightful climate for outdoor adventures.

The height of summer in Niterói occurs from December to February. During this time, the sea temperature maintains a warm range, fluctuating between 24°C (75.2°F) in December and 25.3°C (77.5°F) in February. Moreover, daylight hours peak at an impressive 13.5 hours during December, gradually decreasing to 12.9 hours in February. This extended sunlight paired with balmy sea temperatures makes Niterói's summer a period of unending beach days.

Autumn, from March to May in Niterói, is marked by a steady decrease in sea temperature from 25.8°C (78.4°F) in March to 23.3°C (73.9°F) in May. Conversely, daylight hours decrease from 12.2 hours in March to 11 hours by May. Despite these reductions, the temperate climate in autumn assures an abundance of recreational outdoor opportunities.

Niterói's winter, spanning June to August, maintains a lower sea temperature range, 22.1°C (71.8°F) in June and 22.3°C (72.1°F) in August, and shorter daylight hours between 10.7 in June, extending slightly to 11.3 in August. Even during winter, temperatures remain relatively warm, with enough daylight for sightseeing or indulging in local festivities.

Niterói in January is characterized by warm sea temperatures, creating a welcoming environment for swimming or water sports. This period reveals a mild shift from the hotter months due to a slight drop in sunlight hours. While there might be a refreshing breeze around, it does not pose any discomfort for outdoor activities. Weather in January »

Following January, February is a pleasant time to visit Niterói as the weather remains consistent. A slightly noticeable decrease in daylight hours, does not imply a significant change in weather conditions. Outdoor festivals and beach visits are still very popular among the locals and tourists alike. Weather in February »

As March arrives, there's a slight increase in sea temperature to 25.8°C (78.4°F), making Niterói's waters exceptionally warm. However, the days become shorter with an average of 12.2 hours of daylight, a subtle transition towards the winter season. Weather in March »

April in Niterói brings about a decline in sea temperature to 25.4°C (77.7°F), noting the end of the peak warmth encountered in the preceding month. The progression in decline of daylight hours from 12.2 hours in March to 11.6 hours in April is a signal of climate transition towards cooler conditions. Weather in April »

Entering May, Niterói starts to welcome the chillier part of the year with sea temperatures dropping to 24.3°C (75.7°F). The average daylight hours also decrease to 11 hours, yet still pleasing for those seeking outdoor activities. Weather in May »

With June comes the shortest day of the year, with daylight hours dropping to 10.7 hours. However, this does not overshadow the alluring beauty of Niterói. The decline in sea temperature to 23.3°C (73.9°F) hints at the arrival of winter, yet without any severe chill to restrict beach activities. Weather in June »

July is the coolest month, with the sea temperature dipping to 22.1°C (71.8°F). As winters set in, locals and visitors adapt to this change. However, the climatic conditions do not limit the scope of outdoor activities in Niterói. Weather in July »

During August, daylight hours in Niterói see a steady increase to 11.3 hours. Sea temperatures too mark a change, climbing slightly to 22.3°C (72.1°F). Today, it’s the season transition phase, moving towards more extended days and increasing warmth. Weather in August »

As September ushers in, temperatures in Niterói's sea marginally decrease to 21.6°C (70.9°F). Notwithstanding, the sea conditions remain conducive for water-related activities. A shift towards extended daylight hours marks this period, incrementing to an average of 12 hours, contributing to the city's charm. Weather in September »

October in Niterói witnesses a rise in sea temperature with a surge to 22.7°C (72.9°F). As days become longer, averaging about 12.6 daylight hours, outdoor activities become increasingly attractive. The rise in sea temperature welcomes swimmers to enjoy the waters. Weather in October »

November in Niterói marks the prelude to the hotter part of the year, with a noticeable increase in sea temperature to 23.2°C (73.8°F). Longer daylight hours of 13.2 suggest a climatic shift towards summer. The change in sea temperature indicates a more welcoming environment for swimmers and water sports enthusiasts. Weather in November »

In December, Niterói welcomes its warmest month with sea temperatures peeking at 24°C (75.2°F). The city basks under the sun for the longest during this month, with an average of 13.5 daylight hours. As the year draws to its close, Niterói's weather conditions remain favorable to outdoor enthusiasts. Weather in December »