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 snowfall in September
- Average snowfall 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 shift from August to September coincides with a small decrease in the average high-temperature, down to a moderately hot 81.9°F (27.7°C) from a hot 87.4°F (30.8°C). Throughout September, Apex's nights cool down to an average of 63.9°F (17.7°C).Heat index
The heat index in September is evaluated at a tropical 87.8°F (31°C). With prolonged exposure and constant activity, one might feel exhausted and experience heat cramps.In terms of the heat index, values are set with light wind and shade conditions in mind. Heat index values may be hiked up by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is a composite of temperature and humidity figures to convey how warm it feels. The individual's impression of temperature can be shaped by additional aspects such as metabolic variations, physical activity, and clothing. Direct sunlight can potentially raise the heat index by 15 Fahrenheit (8 Celsius) degrees, so it's crucial to consider. Heat index values hold great significance to 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.
Humidity
In September, the average relative humidity is 75%.Rainfall
In Apex, in September, it is raining for 12.5 days, with typically 2.36" (60mm) of accumulated precipitation. Throughout the year, there are 161.9 rainfall days, and 31.18" (792mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
The average length of the day in September is 12h and 23min.On the first day of September, sunrise is at 6:47 am and sunset at 7:42 pm. On the last day of the month, sunrise is at 7:10 am and sunset at 7:00 pm EDT.
Sunshine
In September, the average sunshine is 9.2h.UV index
In September, the average daily maximum UV index is 5. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the ordinary person.Note: A maximum high daily UV index of 5 during September translates into the following directions:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. Given the potency of the midday Sun's UV radiation, one should avoid prolonged exposure. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Apex in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
How many hours of daylight does Apex have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Apex have in September?
How high is the UV index in September?
Average temperature in September
Apex, NC
- Average high temperature in September: 81.9°F
The warmest month (with the highest average high temperature) is July (89.8°F).
The month with the lowest average high temperature is January (48°F).
- Average low temperature in September: 63.9°F
The month with the highest average low temperature is July (70.9°F).
The coldest month (with the lowest average low temperature) is January (32.5°F).
Average pressure in September
Apex, NC
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is November (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.96"Hg).
Average wind speed in September
Apex, NC
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is April (7.8mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in September
Apex, NC
- Average humidity in September: 75%
The month with the highest relative humidity is December (76%).
The month with the lowest relative humidity is July (71%).
Average rainfall in September
Apex, NC
- Average rainfall in September: 2.36"
The wettest month (with the highest rainfall) is May (3.15").
The driest month (with the least rainfall) is October (2.17").
Average rainfall days in September
Apex, NC
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is July (17.9 days).
The month with the least rainy days is November (9.1 days).
Average snowfall in September
Apex, NC
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.61").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Apex, NC
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.3 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Apex, NC
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in September: 9h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is December (Average sunshine: 5h and 30min).
Average sunshine days in September
Apex, NC
- Average sunshine days in September: 15.5 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is July (11.3 days).
Average UV index in September
Apex, NC
- Average UV index in September: 5
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is January (UV index 2).
Average cloud cover in September
Apex, NC
- Average cloud cover in September: 35
The month with the most cloud cover is February (Cloud cover 42).
The month with the least cloud cover is June (Cloud cover 30).
Average visibility in September
Apex, NC
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Apex, North Carolina, USA
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