March weather forecast
Castanhal, Brazil

The first month of the autumn, March, is also a moderately hot month in Castanhal, Brazil, with an average temperature fluctuating between 29.7°C (85.5°F) and 22.6°C (72.7°F).

Temperature

Castanhal's coldest months, March and April, record an average high-temperature of 29.7°C (85.5°F).

Heat index

March's average heat index is calculated to be a scorching 40°C (104°F). Implement additional cautionary measures, heat cramps and heat exhaustion could occur. Prolonged activity might induce heatstroke.
Realize that the values for the heat index are set for shaded places and light winds. 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 'felt air temperature' or 'real feel', is a metric representing the sensation of warmth when air temperature and moisture come together. An individual's perception of weather can be swayed by a variety of elements including metabolic differences, pregnancy status, and their level of physical exertion. Direct exposure to sun rays can potentially augment the heat sensation, elevating the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Children regularly disregard the necessity to rest and replenish fluids. Thirst is a late symptom of dehydration - thus, maintaining hydration, particularly during long-lasting physical activities, is essential.
The body's self-cooling mechanism is rooted in perspiration, where evaporating sweat cools down excessive warmth. When the air contains significant moisture, the efficiency of the evaporation process decreases, preventing the body from cooling down effectively and creating a feeling of overheating. If the body retains more heat than it can expel, the increasing temperature can lead to heat-related conditions.

Humidity

In Castanhal, the average relative humidity in March is 91%.

Rainfall

The month with the most rainfall in Castanhal, Brazil, is March, when the rain falls for 30.8 days and typically aggregates up to 252mm (9.92") of precipitation.

Daylight

In Castanhal, the average length of the day in March is 12h and 7min.
On the first day of the month, sunrise is at 06:19 and sunset at 18:27. On the last day of March, sunrise is at 06:12 and sunset at 18:18 -03.

Sunshine

March has the least sunshine of the year, with an average of 5.6h of sunshine.

UV index

The months with the lowest UV index are January through April, June, August and December, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health hazard from exposure to the Sun's UV radiation for the ordinary person.
Note: In March, a regular UV index of 6 translates into these guidelines:
Adopt measures and apply sun safety strategies. Shielding from skin and eye damage is necessary. Avoid direct sunlight between the hours of 10 a.m. and 4 p.m., when UV radiation is at its peak. Keep in mind that shade structures may not provide complete protection. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.