September weather forecast
Bula, Guinea-Bissau

September brings the rain-soaked phase to a close, with rainfall figures dropping down to 132mm (5.2") from August's peak. Temperature begins its upward journey again, reaching a comfortable 30.5°C (86.9°F) high. The number of sunshine days also takes an upward swing, signaling the start of the drier months. Wind speeds drop, creating calm conditions and making September a pleasant transition between the wet and the dry periods. The cloud cover sees a downtick, paving the way for clearer skies and enhanced visibility.

Temperature

The arrival of September brings an average high-temperature of a tropical 30.5°C (86.9°F), closely following the temperature pattern of August. In Bula, the September nights cool down to an average low of 25°C (77°F).

Heat index

During September, the heat index is estimated at an extremely hot 40°C (104°F). Incorporate additional preventive steps, heat exhaustion and heat cramps are possible. Long-lasting activity may cause heatstroke.
Be aware that heat index ratings are designed for shaded locations and minor breezes. The heat index could see an increase by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is a metric representing the sensation of warmth when air temperature and moisture come together. One's weather perception can be influenced by a range of factors including metabolic differences, being pregnant, and their level of physical activity. Should you be directly under the sun, anticipate a possible increase in the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are of high significance for children. Young ones often underestimate the need for rest and rehydration. Thirst appears late in dehydration - hence, it is important to keep hydrated, particularly during prolonged physical activities.
The body's inherent cooling system operates through perspiration, wherein evaporating sweat offsets excessive heat. Under conditions of increased relative humidity, the evaporation rate lessens, causing the body to retain more heat than under less humid conditions. Inadequate heat shedding in the face of rising body temperatures hints at potential dehydration risks.

Humidity

In September, the average relative humidity is 81%.

Rainfall

In Bula, in September, during 20.7 rainfall days, 132mm (5.2") of precipitation is typically accumulated. In Bula, Guinea-Bissau, during the entire year, the rain falls for 107.5 days and collects up to 726mm (28.58") of precipitation.

Daylight

The average length of the day in September is 12h and 11min.
On the first day of September, sunrise is at 06:52 and sunset at 19:13. On the last day of the month, sunrise is at 06:51 and sunset at 18:53 GMT.

Sunshine

In Bula, the average sunshine in September is 7.5h.

UV index

January through December, with an average maximum UV index of 7, are months with the highest UV index in Bula. January through December, with an average maximum UV index of 7, are months with the lowest UV index. A UV Index reading of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for the ordinary person.
Note: In September, a daily maximum UV index of 7 leads to the following instructions:
Beware of overexposure. Fair-skinned individuals risk burning in less than 20 minutes. UV radiation from the sun is at its strongest between 10 a.m. and 4 p.m. Try to limit direct exposure during these hours. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage.