July weather forecast
São Luís, Brazil

July marks a notable change in São Luís's weather patterns, with rainfall dipping significantly to 131mm (5.16"), highlighting the progression of the dry season. The temperature scale reveals a slight dip in comparison to June. Moreover, daylight hours maintain their consistency, registering yet again at 12 hours. The UV index remains unchanged from June's value at 10. July affirms the presence of the dry season, with sharp reductions in rainfall and stable temperatures.

Temperature

São Luís experiences a minor change to a still hot 30.2°C (86.4°F) in average high-temperature during July, closely reflecting June. Throughout July nights, São Luís registers an average low-temperature of 22.6°C (72.7°F).

Heat index

For July, the heat index is appraised at an extremely hot 40°C (104°F). Heightened precautions are necessary, heat cramps and heat exhaustion are potential risks. Continuous activity could lead to heatstroke.
It is crucial to understand that heat index figures are for shade and gentle wind conditions. Uninterrupted exposure to the sun may boost the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', binds temperature metrics with humidity values to give a sense of the actual warmth. The influence of weather is personal, with a diverse population experiencing it differently due to differences in body mass, stature, and degree of activity. Always consider that direct sunlight exposure might heighten the heat's effects, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Young individuals are generally in more danger than adults due to their lower capacity to sweat. Moreover, their large skin surface in relation to their small bodies and the increased heat generation from their activities makes them more vulnerable.
Perspiring is how the human body naturally cools down, as sweat's evaporation takes away excess heat. An increase in relative humidity hinders the body's normal cooling function by reducing evaporation, thereby decreasing the rate of body cooling and enhancing the sense of warmth. Exceeding the body's heat disposal threshold results in a rise in body temperature and potential thermal disorders.

Humidity

In July, the average relative humidity in São Luís is 86%.

Rainfall

In July, the rain falls for 10 days. Throughout July, 131mm (5.16") of precipitation is accumulated. In São Luís, during the entire year, the rain falls for 130 days and collects up to 2290mm (90.16") of precipitation.

Sea temperature

In São Luís, the average seawater temperature in July is 28.3°C (82.9°F).
Note: Swimming, diving, and other activities in water temperatures between 25°C (77°F) and 29°C (84.2°F) are thought to be quite enjoyable and satisfying for extended periods, with no discomfort.

Daylight

The average length of the day in July is 11h and 59min.
On the first day of July in São Luís, Brazil, sunrise is at 06:01 and sunset at 18:00. On the last day of the month, sunrise is at 06:03 and sunset at 18:03 -03.

Sunshine

In São Luís, the average sunshine in July is 7.7h.

UV index

The months with the lowest UV index are June and July, with an average maximum UV index of 10. A UV Index of 8 to 10 symbolizes a very high threat to health from unsafe exposure to UV radiation for average individuals.
Note: The maximum UV index of 10 during July translates into these guidelines:
Being careless can result in skin and eye damage. Always take the necessary safety measures. It's important to stay in the shade and limit exposure to the sun from 10 a.m. to 4 p.m., when UV radiation is most intense, although remember that shade structures may not provide full sun protection. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Even on a cloudy day, a sunscreen with at least a 30 SPF should be applied generously and frequently reapplied, including after a swim or outdoor exercise. Caution! The Sun's UV intensity grows with reflections off sand and water.