September weather forecast
Sámara, Costa Rica

As September dawns in Sámara, Costa Rica, the city experiences a further slight decrease in temperature. The rainfall marks a significant peak, hitting 130mm (5.12"), further reflecting the continuation of the rainy season in the city. Interestingly, despite variable weather conditions, the sea temperature and UV index both remain persistently steady. The daylight hours see a diminutive decrease, while cloud cover ascends to a 49%. An essential peculiarity of September is the decreased winds blowing at an average of 6.9km/h (4.3mph).

Temperature

The transition into September is marked with an average high-temperature of a still moderately hot 29°C (84.2°F), showing an insignificant shift from August's 29.4°C (84.9°F). Sámara observes a minimal variance in temperature, with a consistent average low of 24°C (75.2°F) during the nights of September.

Heat index

For September, the heat index is calculated to be a sweltering 36°C (96.8°F). Incorporate additional safety actions, heat cramps and heat exhaustion are possible. Long-term activity may induce heatstroke.
Heat index guidelines indicate values are for light wind scenarios and shaded regions. Heat index values may be hiked up by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is a value derived by merging air temperature with the humidity to convey how the climate feels. The impact of weather on an individual can be subjective, affected by the person's activity and heat perception, which can vary due to elements including wind, clothing, and metabolic differences. One's exposure to direct sunlight has the potential to intensify the heat sensation, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Young children are generally more endangered than adults, as they usually less sweat. And also, due to larger skin surface relative to their small bodies and higher heat production as a result of their activity.
By perspiring, the human body can shed its excessive warmth since evaporated sweat cools it off. When the level of relative humidity is elevated, evaporation diminishes, causing more warmth to be retained in the body than in dry air. Heat absorption that surpasses the body's shedding capability can lead to overheating and varying levels of dehydration.

Humidity

In Sámara, the average relative humidity in September is 84%.

Rainfall

In Sámara, Costa Rica, in September, it is raining for 24.4 days, with typically 130mm (5.12") of accumulated precipitation. Throughout the year, there are 205 rainfall days, and 1087mm (42.8") of precipitation is accumulated.

Sea temperature

In September, the average sea temperature is 28.8°C (83.8°F).
Note: Surface water temperatures ranging from 25°C (77°F) to 29°C (84.2°F) are considered superb and highly pleasant for water activities over extended periods.

Daylight

The average length of the day in September is 12h and 11min.
On the first day of the month, sunrise is at 05:32 and sunset at 17:50. On the last day of September, sunrise is at 05:30 and sunset at 17:33 CST.

Sunshine

In Sámara, the average sunshine in September is 7.9h.

UV index

The months with the highest UV index are January through December, with an average maximum UV index of 7. The months with the lowest UV index are January through December, with an average maximum UV index of 7. A UV Index of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for average individuals.
Note: In September, the UV index of 7 transforms into the following advice:
Persist with precautions and heed sun safety advice. Prevention of sunburn is compulsory. The hours from 10 a.m. to 4 p.m. have the most intense UV radiation. As much as possible, limit direct sun exposure during this period. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear. Warning! Sand and water reflections boost the intensity of UV exposure.