September weather forecast
Yap, Micronesia

September is another month associated with significant rainfall in Yap, with an average rainfall of 343mm (13.5") recorded. Nevertheless, compared to August, the declining rainfall signals a transition towards drier eras. Temperatures remain steady, and the sea temperatures continue to be warm, making marine activities pleasurable. The decrease in rainfall from its August peak also leads to an increase in sunshine duration, enhancing the potential for outdoor exploits. The transition phase from the wetter months to the less rainy ones brings an exceptional charm to September's weather.

Temperature

The arrival of September records an average high-temperature of a still tropical 30.9°C (87.6°F), closely related to the 30.8°C (87.4°F) observed in August. Yap's average low-temperature during September nights is observed to be a warm 23.5°C (74.3°F).

Heat index

September's heat index is appraised at a scorching 42°C (107.6°F). Ensure additional precautions, heat exhaustion and heat cramps may be expected. Heatstroke could occur from sustained activity.
Thinking about the heat index, one should account for its values in shaded areas with gentle breezes. The heat index has the possibility to be enhanced by 15 Fahrenheit (8 Celsius) degrees when there is direct sun exposure.
Note: The heat index, also known as 'real feel' or 'apparent temperature', combines air temperature and relative humidity to represent a human perceived temperature equivalent. 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. One should be aware that direct sunshine can amplify the perceived temperature, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Children frequently underestimate the importance of resting and drinking fluids. Thirst is a symptom of advanced dehydration - hence the need to hydrate regularly, especially during protracted physical exercises.
To prevent overheating and help regulate its internal temperature, the human body sweat and rely on the evaporation to cool down. When there is abundant moisture in the air, the body's cooling through the evaporation process becomes less effective, leading to the sensation of overheating. Overheating and potential dehydration arise when body heat gain eclipses its release capability.

Humidity

The months with the highest humidity are July through October, with an average relative humidity of 84%.

Rainfall

In Yap, Micronesia, during September, the rain falls for 19.3 days and regularly aggregates up to 343mm (13.5") of precipitation. Throughout the year, there are 211.6 rainfall days, and 3050mm (120.08") of precipitation is accumulated.

Sea temperature

The months with the warmest seawater are May through December, with an average sea temperature of 29°C (84.2°F).
Note: Swimming, diving, and similar water activities in temperatures ranging from 25°C (77°F) to 29°C (84.2°F) are seen as very agreeable and pleasurable for lengthy periods without discomfort.

Daylight

In Yap, the average length of the day in September is 12h and 11min.
On the first day of the month, sunrise is at 06:38 and sunset at 18:56. On the last day of September, in Yap, sunrise is at 06:35 and sunset at 18:38 +10.

Sunshine

In September, the average sunshine is 6h.

UV index

The months with the highest UV index are February through October, with an average maximum UV index of 12. A UV Index of 11, and more, symbolizes an excessive health risk from exposure to the Sun's UV rays for average individuals.
Note: In September, a daily UV index of 12 turns into the following recommendations:
Enforce all necessary safety measures, unprotected skin may suffer burns swiftly. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses. Even when it's cloudy, ensure the generous application and frequent reapplication of a sunscreen with at least 30 SPF, particularly post swim or outdoor activity. Heads up! The reflection of sand and water notably intensifies UV rays from the Sun.