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
With the onset of September, the average high-temperature registers at a moderately hot 85.1°F (29.5°C), subtly different from August's 89.6°F (32°C). Manassas's temperature tends to fall to an average low of 68.5°F (20.3°C) during the nights of September.Heat index
September's mean heat index is appraised at a very hot 95°F (35°C). Heightened safety actions are necessary, heat cramps and heat exhaustion are probable. Persistent activity may lead to heatstroke.Bear in mind that the heat index values are determined for shaded areas and light breezes. The heat index can potentially augment by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is an indicator that blends the effects of temperature and humidity to depict perceived warmth. Elements such as metabolic variations, pregnancy, and physical exertion can shape one's weather perception. It is noteworthy to mention that direct sunlight exposure can augment the felt temperature, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. In general, younger individuals are at greater risk than adults because they tend to sweat less. Also, having a larger skin surface to body size ratio and greater heat production due to their active behavior contribute to this danger.
The natural cooling mechanism in humans involves perspiration, where the evaporation of sweat balances out excessive warmth. In high relative humidity, the body's ability to evaporate heat is diminished, resulting in a heightened feeling of warmth. When body temperature rises due to an imbalance in heat gain, there's a potential for dehydration and overheating.
Humidity
August, September and December, with an average relative humidity of 77%, are the most humid months.Rainfall
In Manassas, in September, during 13.8 rainfall days, 1.38" (35mm) of precipitation is typically accumulated. Throughout the year, in Manassas, there are 149.6 rainfall days, and 22.52" (572mm) of precipitation is accumulated.Snowfall
In Manassas, snow does not fall in February through November.Daylight
In September, the average length of the day is 12h and 21min.On the first day of September in Manassas, Georgia, sunrise is at 7:03 am and sunset at 7:51 pm. On the last day of the month, sunrise is at 7:21 am and sunset at 7:13 pm EDT.
Sunshine
The average sunshine in September in Manassas is 8.5h.UV index
In Manassas, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for ordinary individuals.Note: The UV index of 6 during September leads to these advisories:
Sustain precautions and conform to sun safety norms. Preventing sunburn is necessary. The Sun's UV radiation is most potent between 10 a.m. and 4 p.m. Try to limit direct exposure to the Sun during this period. To cut down UV radiation exposure by about half, sport a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in Manassas in September?
What are the most humid months in Manassas?
What is the average humidity in September in Manassas?
How many days does it rain in September in Manassas?
When it does not snow in Manassas?
What is the average length of the day in September in Manassas?
When is the sunrise / sunset in September in Manassas?
How many hours of sunshine does Manassas have in September?
What is the UV index reading in September in Manassas?
Average temperature in September
Manassas, GA
- Average high temperature in September: 85.1°F
The warmest month (with the highest average high temperature) is July (90.5°F).
The month with the lowest average high temperature is January (57.2°F).
- Average low temperature in September: 68.5°F
The months with the highest average low temperature are July and August (73.2°F).
The coldest month (with the lowest average low temperature) is January (40.6°F).
Average pressure in September
Manassas, GA
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.97"Hg).
Average wind speed in September
Manassas, GA
- Average wind speed in September: 5.9mph
The windiest month (with the highest average wind speed) is April (7.6mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in September
Manassas, GA
- Average humidity in September: 77%
The months with the highest relative humidity are August, September and December (77%).
The month with the lowest relative humidity is January (71%).
Average rainfall in September
Manassas, GA
- Average rainfall in September: 1.38"
The wettest month (with the highest rainfall) is August (2.8").
The driest month (with the least rainfall) is November (1.14").
Average rainfall days in September
Manassas, GA
- Average rainfall days in September: 13.8 days
The month with the highest number of rainy days is August (18.3 days).
The month with the least rainy days is November (7.1 days).
Average snowfall in September
Manassas, GA
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.08").
The months with the least snowfall are February, March, April, May, June, July, August, September, October and November (0").
Average snowfall days in September
Manassas, GA
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are February and March (0.2 days).
The months with the least snowfall days are April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Manassas, GA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 12min).
The month with the shortest days is December (Average daylight: 10h and 6min).
- Average sunshine in September: 8h and 3min
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 18min).
Average sunshine days in September
Manassas, GA
- Average sunshine days in September: 14 days
The month with the most sunshine days is October (21.2 days).
The month with the least sunshine days is July (9.7 days).
Average UV index in September
Manassas, GA
- Average UV index in September: 6
The months with the highest UV index are May, June, July and August (UV index 7).
The month with the lowest UV index is January (UV index 3).
Average cloud cover in September
Manassas, GA
- Average cloud cover in September: 33
The month with the most cloud cover is December (Cloud cover 42).
The months with the least cloud cover are July and October (Cloud cover 30).
Average visibility in September
Manassas, GA
- 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).
Manassas, Georgia, USA
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