September weather forecastGrace, Saint Lucia
September
Weather in September
September continues to sustain high temperatures in Grace, Saint Lucia, but with a reduced wind speed. The reduced wind speed and shorter daylight hours often result in the days feeling hotter. Rainfall in September is quite substantial but slightly less when compared to the previous month. The climatological data reveals an average rainfall of 64mm (2.52") in September in Grace, Saint Lucia. As September gives way to October, there's a slight increase in rainfall and a decrease in temperatures.Temperature
Grace's warmest season falls during September and October, averaging a high-temperature of 29.5°C (85.1°F).Heat index
The heat index for September is computed to be a torrid 35°C (95°F). Adopt special protective actions against heat exhaustion and heat cramps. Long-duration activity risks heatstroke.Remember that heat index calculations are made for conditions in the shade with light wind. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', combines air temperature and relative humidity to represent a 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. Direct sunlight can potentially raise the heat index by 15 Fahrenheit (8 Celsius) degrees, so it's crucial to consider. Heat index values are particularly meaningful for babies and toddlers. Children frequently do not comprehend the need for rest and hydration. Thirst is an advanced stage of dehydration - staying hydrated, especially during extended physical exercises, is essential.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. In situations of high air temperature combined with high humidity (significant heat index), the body's ability to perspire is reduced, heightening the sense of warmth. Inadequate heat shedding in the face of rising body temperatures hints at potential dehydration risks.
Humidity
In September, the average relative humidity is 75%.Rainfall
In September, in Grace, Saint Lucia, the rain falls for 19.5 days. Throughout September, 64mm (2.52") of precipitation is accumulated. In Grace, during the entire year, the rain falls for 232.4 days and collects up to 542mm (21.34") of precipitation.Daylight
In September, the average length of the day in Grace is 12h and 12min.On the first day of the month, sunrise is at 05:52 and sunset at 18:15. On the last day of September, sunrise is at 05:53 and sunset at 17:54 AST.
Sunshine
In September, the average sunshine is 10.1h.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 estimate of 6 to 7 represents a high health risk from unsafe exposure to UV radiation for the ordinary person.Note: The UV index of 7 during September leads to these advisories:
Avert overexposure. Light-skinned people might experience burning in less than 20 minutes. Stay in the shade and limit direct Sun exposure from 10 a.m. to 4 p.m., a time when UV radiation is particularly strong. Remember, however, that shade structures may not provide complete protection. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Grace, Saint Lucia
- Average high temperature in September: 29.5°C
The warmest months (with the highest average high temperature) are September and October (29.5°C).
The month with the lowest average high temperature is February (26.8°C).
- Average low temperature in September: 27.6°C
The month with the highest average low temperature is September (27.6°C).
The coldest month (with the lowest average low temperature) is February (25.3°C).
Average pressure in September
Grace, Saint Lucia
- Average pressure in September: 1012.5mbar
The month with the highest atmospheric pressure is June (1014.9mbar).
The month with the lowest atmospheric pressure is November (1011.3mbar).
Average wind speed in September
Grace, Saint Lucia
- Average wind speed in September: 18.3km/h
The windiest month (with the highest average wind speed) is February (26.9km/h).
The calmest month (with the lowest average wind speed) is September (18.3km/h).
Average humidity in September
Grace, Saint Lucia
- Average humidity in September: 75%
The month with the highest relative humidity is July (77%).
The months with the lowest relative humidity are January and February (74%).
Average rainfall in September
Grace, Saint Lucia
- Average rainfall in September: 64mm
The wettest month (with the highest rainfall) is October (73mm).
The driest month (with the least rainfall) is February (18mm).
Average rainfall days in September
Grace, Saint Lucia
- Average rainfall days in September: 19.5 days
The month with the highest number of rainy days is July (23.3 days).
The month with the least rainy days is February (15 days).
Average daylight in September /
Average sunshine in September
Grace, Saint Lucia
- Average daylight in September: 12h and 12min
The month with the longest days is June (Average daylight: 12h and 54min).
The month with the shortest days is December (Average daylight: 11h and 18min).
- Average sunshine in September: 10h and 6min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is December (Average sunshine: 6h and 36min).
Average sunshine days in September
Grace, Saint Lucia
- Average sunshine days in September: 7.1 days
The month with the most sunshine days is March (9.1 days).
The month with the least sunshine days is July (3.6 days).
Average UV index in September
Grace, Saint Lucia
- Average UV index in September: 7
The months with the highest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 7).
Average cloud cover in September
Grace, Saint Lucia
- Average cloud cover in September: 37
The month with the most cloud cover is June (Cloud cover 46).
The month with the least cloud cover is February (Cloud cover 35).
Average visibility in September
Grace, Saint Lucia
- Average visibility in September: 10km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).





