Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The months of September and October bring the highest temperatures, averaging a high of 30.9°C (87.6°F).Heat index
The heat index for September is computed to be a blisteringly hot 40°C (104°F). Take more preventive steps, risk of heat exhaustion and heat cramps is elevated. Long activity may culminate in heatstroke.The heat index's values are generally associated with conditions in shade and light breezes. Facing direct sunlight may hike up the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. The impression of weather on a person can be swayed by additional aspects, including metabolic variations, pregnancy, and activity levels. It is noteworthy that being in direct sunlight can enhance the weather's impact, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are of high significance for children. Children often overlook the necessity for resting and fluid replenishment. Thirst is a late sign of dehydration - thus, it is critical to stay hydrated, especially during extended periods of physical activities.
One way the human body deals with excessive warmth is by perspiring and allowing sweat to evaporate. With higher relative humidity, the rate of evaporation is reduced, resulting in increased heat retention in the body compared to drier air. Excessive heat that's not properly managed leads to increased body temperatures and resultant health issues.
Humidity
The months with the lowest humidity in Mont Valérien are September and October, with an average relative humidity of 77%.Rainfall
September is the month with the least rainfall. Rain falls for 14.3 days and accumulates 29mm (1.14") of precipitation.Daylight
The average length of the day in September in Mont Valérien is 12h and 8min.On the first day of the month, sunrise is at 06:25 and sunset at 18:38. On the last day of September, in Mont Valérien, sunrise is at 06:19 and sunset at 18:24 -03.
Sunshine
September has the most sunshine of the year, with an average of 9.3h of sunshine.UV index
July through November, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: The maximum daily UV index of 7 during September translates into the following directions:
Persist with precautions and heed sun safety advice. Prevention of sunburn is compulsory. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Frequently asked questions
What time of the year is the hottest in Mont Valérien?
How hot does it get in Mont Valérien in September?
What is the least humid month in Mont Valérien?
What is the average humidity in September in Mont Valérien?
What is the driest month in Mont Valérien?
How many days does it rain in September in Mont Valérien?
What is the average length of the day in September in Mont Valérien?
When are sunrise and sunset in September in Mont Valérien?
What month has the most sunshine in Mont Valérien?
How long on average sun shines in September in Mont Valérien?
When is the highest UV index in Mont Valérien?
How high is the UV index in September in Mont Valérien?
Average temperature in September
Mont Valérien, French Guiana
- Average high temperature in September: 30.9°C
The warmest months (with the highest average high temperature) are September and October (30.9°C).
The month with the lowest average high temperature is February (27.5°C).
- Average low temperature in September: 24.8°C
The month with the highest average low temperature is November (25.1°C).
The coldest month (with the lowest average low temperature) is January (24.2°C).
Average pressure in September
Mont Valérien, French Guiana
- Average pressure in September: 1012mbar
The months with the highest atmospheric pressure are June and July (1013.1mbar).
The month with the lowest atmospheric pressure is November (1009.7mbar).
Average wind speed in September
Mont Valérien, French Guiana
- Average wind speed in September: 12.7km/h
The windiest month (with the highest average wind speed) is February (15.3km/h).
The calmest month (with the lowest average wind speed) is July (9.7km/h).
Average humidity in September
Mont Valérien, French Guiana
- Average humidity in September: 77%
The months with the highest relative humidity are February and May (84%).
The months with the lowest relative humidity are September and October (77%).
Average rainfall in September
Mont Valérien, French Guiana
- Average rainfall in September: 29mm
The wettest month (with the highest rainfall) is May (279mm).
The driest month (with the least rainfall) is September (29mm).
Average rainfall days in September
Mont Valérien, French Guiana
- Average rainfall days in September: 14.3 days
The month with the highest number of rainy days is May (29.6 days).
The months with the least rainy days are September and October (14.3 days).
Average daylight in September /
Average sunshine in September
Mont Valérien, French Guiana
- Average daylight in September: 12h and 1min
The month with the longest days is June (Average daylight: 12h and 24min).
The month with the shortest days is December (Average daylight: 11h and 48min).
- Average sunshine in September: 9h and 2min
The month with the most sunshine is September (Average sunshine: 9h and 18min).
The month with the least sunshine is February (Average sunshine: 5h and 48min).
Average sunshine days in September
Mont Valérien, French Guiana
- Average sunshine days in September: 11.6 days
The month with the most sunshine days is October (13.2 days).
The month with the least sunshine days is May (0.6 days).
Average UV index in September
Mont Valérien, French Guiana
- Average UV index in September: 7
The months with the highest UV index are July, August, September, October and November (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June and December (UV index 6).
Average cloud cover in September
Mont Valérien, French Guiana
- Average cloud cover in September: 25
The month with the most cloud cover is February (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 25).
Average visibility in September
Mont Valérien, French Guiana
- Average visibility in September: 10km
The months with the highest visibility are January, February, March, April, August, September, October, November and December (10km).
The months with the lowest visibility are May, June and July (9km).
Mont Valérien, French Guiana
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