January weather forecast
Fortaleza, Brazil

Kickstarting the year in Fortaleza, Brazil, January presents a striking mix of air, water and sunshine elements. The display of the month sees a typical high temperature of 30.5°C (86.9°F) combined with relative humidity reaching 78.1%. Daylight stretches out to an average of 12.3 hours, offering quite the opportunity to explore all that Fortaleza has to offer. The month is also highlighted by an average rainfall of 119mm (4.69"), making it one the rainiest season to explore the city. While the humid, tropical climate is palpable, the cooler sea at 28.2°C (82.8°F) comes as soothing respite.

Temperature

Fortaleza registers an average high-temperature of a still tropical 30.5°C (86.9°F) with the arrival of January, showing minor deviation from the preceding month. Fortaleza records an average nighttime low-temperature of 24.4°C (75.9°F) throughout January.

Heat index

In January, the average heat index is estimated at a very hot 39°C (102.2°F). Adopt extra safety steps, risk of heat exhaustion and heat cramps is notable. Sustained activity might cause heatstroke.
Bear in mind that the heat index values are determined for shaded areas and light breezes. The presence of direct sunlight can raise the heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', reflects the feeling of heat when considering both air temperature and humidity. The impact of weather is personal, differing among a variety of people based on differences in body mass, height, and the level of physical exertion. The sun, when shining directly, can have a significant impact on the perceived temperature, increasing the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Children often fail to understand the importance of rest and rehydration. Thirst is a late manifestation of dehydration - hence, it is crucial to stay hydrated, especially during ongoing physical activities.
The human body cools itself through perspiration, as excessive warmth is removed from the body through sweat evaporation. With an abundance of moisture present in the air, the process of evaporation becomes less effective, and the body fails to cool down as it should, leading to the sensation of overheating. Overheating risks increase with rising body temperatures, especially if heat release isn't efficient.

Humidity

The average relative humidity in January in Fortaleza, Brazil, is 78.1%.

Rainfall

In Fortaleza, during January, the rain falls for 11 days and regularly aggregates up to 119mm (4.69") of precipitation. Throughout the year, there are 135 rainfall days, and 1608mm (63.31") of precipitation is accumulated.

Sea temperature

In January, the average sea temperature is 28.2°C (82.8°F).
Note: Surface water temperatures ranging from 25°C (77°F) to 29°C (84.2°F) are seen as ideal and highly pleasant for extended enjoyment in all water activities.

Daylight

In January, the average length of the day in Fortaleza is 12h and 19min.
On the first day of January in Fortaleza, sunrise is at 05:27 and sunset at 17:47. On the last day of the month, sunrise is at 05:39 and sunset at 17:55 -03.

Sunshine

In January, the average sunshine is 7.3h.

UV index

January through April, September through December, with an average maximum UV index of 12, are months with the highest UV index. A UV Index reading of 11, and higher, represents an extreme health hazard from exposure to the Sun's UV rays for ordinary individuals.
Note: The maximum UV index of 12 during January translates into these guidelines:
Adopt every precaution of necessity, unprotected skin and eyes may suffer burns instantly. Attempt to stay under shade and limit exposure to the Sun between 10 a.m. and 4 p.m., when UV radiation is at its peak. Remember, devices such as parasols or canopies might not provide complete sun protection. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. After a swim or an outdoor workout, generously apply and reapply a broad-spectrum SPF 30+ sunscreen. Caution! Sand and water surfaces escalate the UV intensity from the Sun.