September weather forecast
Punta Santiago, PR

By September, the weather in Punta Santiago begins to cool down slightly, heralding the slow transition towards the fall season. The overall temperature displays a marginal decrease and rainfall begins to drop. A decrease in wind speed is also noticeable. However, despite the weather changes, humidity remains consistent with the summer months. Even though temperatures remain high at 84.6°F (29.2°C), the sea temperatures begin to cool down, somewhat moderating the weather, and rainfall decreases to 4.33" (110mm) over approximately 24.5 days.

Temperature

September begins with an average high-temperature of a still moderately hot 84.6°F (29.2°C), reflecting close similarity to the preceding month. September's average low-temperature is a still moderately hot 78.6°F (25.9°C), reflecting a minor difference from the day's peak temperatures.

Heat index

Throughout September, the heat index is calculated to be a fiery hot 95°F (35°C). Extra precautions are necessary, heat cramps and heat exhaustion are plausible outcomes. Extended activity could lead to heatstroke.
Understand that the heat index values take into account shaded locations and mild winds. Exposure to the sun directly might heighten the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is a calculated temperature value of how hot it feels when the moisture in the air is factored in. This effect is personal, shaped by the individual's physical activity and heat sensitivity, influenced by factors including wind, clothing, and metabolic variances. Consider the sun's direct rays and their impact; they can potentially increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. Children often do not understand the need to rest and hydrate. Thirst is a late manifestation of dehydration - therefore, it is essential to stay hydrated, particularly during prolonged physical activities.
By perspiring, the human body can shed its excessive warmth since evaporated sweat cools it off. With high air temperature and humidity (high heat index) conditions, sweat production is restricted, leading to an amplified perception of heat. When body temperature rises due to excess heat gain beyond its removal capability, one might experience heat-related disorders.

Humidity

In September, the average relative humidity is 79%.

Rainfall

In Punta Santiago, during September, the rain falls for 24.5 days and regularly aggregates up to 4.33" (110mm) of precipitation. In Punta Santiago, during the entire year, the rain falls for 268.8 days and collects up to 38.58" (980mm) of precipitation.

Ocean temperature

The month with the warmest seawater in Punta Santiago is September, with an average ocean temperature of 84.9°F (29.4°C).
Note: For any water activity, the surface water temperatures in the range of 77°F (25°C) to 84.2°F (29°C) are deemed excellent and incredibly pleasant for longer durations.

Daylight

In September, the average length of the day in Punta Santiago is 12h and 14min.
On the first day of September in Punta Santiago, sunrise is at 6:08 am and sunset at 6:36 pm. On the last day of the month, sunrise is at 6:13 am and sunset at 6:12 pm AST.

Sunshine

In September, the average sunshine in Punta Santiago is 9.1h.

UV index

April through December, with an average maximum UV index of 7, are months with the highest UV index in Punta Santiago, Puerto Rico. A UV Index reading of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: A maximum high daily UV index of 7 during September translates into the following directions:
Take precautions and adopt sun safety practices. Protection against sunburn is obliged. Stay in the shade and limit sun exposure from 10 a.m. to 4 p.m., when UV radiation is most potent. Keep in mind that shade structures like parasols or canopies do not offer full protection. During bright days, sunglasses that offer UVA and UVB defense are recommended. Stay cautious! Sand and water reflections increase UV radiation potency.