September weather forecastGressier, Haiti
September
Weather in September
September's weather in Gressier offers a respite as temperatures begin to dip while retaining the tropical charm. This subtle drop in temperature, a transition from the hot August to the cooler October, provides a relief to residents and tourists. September ranks high on the rainfall scale with an average precipitation of 135mm (5.31"), maintaining the humidity in the region. Despite the high rainfall, the sea temperature indicates a warm aquatic environment ideal for various water activities. The steady daylight hours and ample sunshine, even though slightly reduced, support a wide range of outdoor activities.Temperature
The start of September in Gressier sees the average high-temperature at a warm 29.8°C (85.6°F), showing little difference from August's 30.9°C (87.6°F). The average low-temperature of 21.3°C (70.3°F) is witnessed in Gressier during September.Heat index
September's average heat index is evaluated at a fiery hot 36°C (96.8°F). Incorporate additional safety actions, heat cramps and heat exhaustion are possible. Long-term activity may induce heatstroke.Bear in mind that the heat index values are determined for shaded areas and light breezes. When exposed to the direct sun, the heat index may augment by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is an index that combines air temperature and relative humidity to determine the human-perceived temperature equivalent. This impact is subjective, influenced by the person's physical activity and individual heat perception, affected by factors including wind, attire, and metabolic differences. Being aware that direct sunlight can impact the felt heat might mean an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are largely significant for babies and toddlers. Youngsters are usually more at risk than adults, considering they sweat less. Additionally, their high skin surface area compared to their little bodies and their high heat production due to activity increases their risk.
Perspiration is the body's default response to elevated temperatures, as it promotes the evaporation of sweat to achieve cooling. When the air contains significant moisture, the efficiency of the evaporation process decreases, preventing the body from cooling down effectively and creating a feeling of overheating. If the body retains more heat than it can expel, the increasing temperature can lead to heat-related conditions.
Humidity
In Gressier, the average relative humidity in September is 77%.Rainfall
In Gressier, in September, during 22.4 rainfall days, 135mm (5.31") of precipitation is typically accumulated. In Gressier, Haiti, during the entire year, the rain falls for 227.4 days and collects up to 904mm (35.59") of precipitation.Sea temperature
The month with the warmest seawater is September, with an average sea temperature of 29.9°C (85.8°F).Note: Between 25°C (77°F) and 29°C (84.2°F), water temperature is typically considered very warm and pleasurable by everyone. Water activities at these temperatures are enjoyable for extended periods without discomfort.
Daylight
In Gressier, the average length of the day in September is 12h and 14min.On the first day of September in Gressier, sunrise is at 06:35 and sunset at 19:04. On the last day of the month, sunrise is at 06:40 and sunset at 18:39 EDT.
Sunshine
The average sunshine in September in Gressier is 9.6h.UV index
The months with the lowest UV index in Gressier are January through May, July through December, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high health hazard from exposure to the Sun's UV radiation for average individuals.Note: The UV index of 6 during September translates into the following guidance:
Avoid overexposure. Fair-skinned individuals can burn in under 20 minutes. Remember that UV radiation from the Sun is strongest between 10 a.m. and 4 p.m. Make an effort to limit direct sun exposure during this time. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Be mindful! Sand and water reflections can up the Sun's UV exposure.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Gressier, Haiti
- Average high temperature in September: 29.8°C
The warmest month (with the highest average high temperature) is August (30.9°C).
The month with the lowest average high temperature is January (27.6°C).
- Average low temperature in September: 21.3°C
The months with the highest average low temperature are August and September (21.3°C).
The coldest month (with the lowest average low temperature) is January (18.2°C).
Average pressure in September
Gressier, Haiti
- Average pressure in September: 1013.2mbar
The month with the highest atmospheric pressure is January (1016.3mbar).
The month with the lowest atmospheric pressure is October (1012.5mbar).
Average wind speed in September
Gressier, Haiti
- Average wind speed in September: 6.5km/h
The windiest month (with the highest average wind speed) is June (9.2km/h).
The calmest month (with the lowest average wind speed) is September (6.5km/h).
Average humidity in September
Gressier, Haiti
- Average humidity in September: 77%
The month with the highest relative humidity is November (80%).
The month with the lowest relative humidity is February (72%).
Average rainfall in September
Gressier, Haiti
- Average rainfall in September: 135mm
The wettest month (with the highest rainfall) is May (141mm).
The driest month (with the least rainfall) is January (12mm).
Average rainfall days in September
Gressier, Haiti
- Average rainfall days in September: 22.4 days
The months with the highest number of rainy days are April and October (24.4 days).
The month with the least rainy days is January (9.9 days).
Average sea temperature in September
Gressier, Haiti
- Average sea temperature in September: 29.9°C
The best month for swimming (with the highest average sea temperature) is September (29.9°C).
The coldest month (with the lowest average sea temperature) is February (26.9°C).
Average daylight in September /
Average sunshine in September
Gressier, Haiti
- Average daylight in September: 12h and 12min
The month with the longest days is June (Average daylight: 13h and 12min).
The month with the shortest days is December (Average daylight: 11h and 0min).
- Average sunshine in September: 9h and 36min
The month with the most sunshine is July (Average sunshine: 11h and 18min).
The month with the least sunshine is February (Average sunshine: 7h and 12min).
Average sunshine days in September
Gressier, Haiti
- Average sunshine days in September: 4.7 days
The month with the most sunshine days is December (19 days).
The month with the least sunshine days is April (3.3 days).
Average UV index in September
Gressier, Haiti
- Average UV index in September: 6
The month with the highest UV index is June (UV index 7).
The months with the lowest UV index are January, February, March, April, May, July, August, September, October, November and December (UV index 6).
Average cloud cover in September
Gressier, Haiti
- Average cloud cover in September: 27
The month with the most cloud cover is April (Cloud cover 35).
The month with the least cloud cover is December (Cloud cover 21).
Average visibility in September
Gressier, Haiti
- Average visibility in September: 9km
The months with the highest visibility are February, March and June (10km).
The months with the lowest visibility are January, April, May, July, August, September, October, November and December (9km).





