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
As Fairfax transitions into September, the average high-temperature stands at a moderately hot 84.9°F (29.4°C), offering little variation from the preceding month. Fairfax's nighttime temperature in September falls to an average of 68.2°F (20.1°C).Heat index
September's heat index is computed to be a fiery hot 95°F (35°C). Extra safeguards are necessary to prevent heat exhaustion and heat cramps. Prolonged activity might cause heatstroke.It is important to note that the heat index values are for shaded areas and light wind scenarios. Heat index values have the potential to be boosted by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is found by incorporating humidity levels into the air temperature measurement. The impact of weather is personal, differing among a variety of people based on differences in body mass, height, and the level of physical exertion. 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 extremely significant 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.
Perspiring is a crucial mechanism for the human body, allowing it to release excessive warmth through evaporating sweat. A surge in relative humidity can disrupt the body's normal cooling function by slowing evaporation, hence reducing the rate at which the body cools and intensifying the perception of heat. 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 Fairfax, in September, during 13.9 rainfall days, 1.97" (50mm) of precipitation is typically accumulated. Throughout the year, there are 152.9 rainfall days, and 31.18" (792mm) of precipitation is accumulated.Snowfall
In Fairfax, snow does not fall in March through December.Daylight
In Fairfax, South Carolina, the average length of the day in September is 12h and 22min.On the first day of the month, sunrise is at 6:59 am and sunset at 7:49 pm. On the last day of September, in Fairfax, sunrise is at 7:18 am and sunset at 7:10 pm EDT.
Sunshine
In September, the average sunshine is 8.4h.UV index
In September, the average daily maximum UV index is 6. A UV Index value of 6 to 7 symbolizes a high health risk from unsafe exposure to UV radiation for the average person.Note: During September, 6 as the daily maximum UV index converts into the following advice:
Follow precautions and abide by sun safety rules. Deterrence of sunburn is imperative. 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. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
Frequently asked questions
How hot is it in Fairfax in September?
What is the average humidity in September in Fairfax?
How much does it rain in Fairfax in September?
When it does not snow in Fairfax?
How many hours of daylight does Fairfax have in September?
What time are sunrise and sunset in September in Fairfax?
How long on average sun shines in September in Fairfax?
What is the UV index intensity in September in Fairfax?
Average temperature in September
Fairfax, SC
- Average high temperature in September: 84.9°F
The warmest month (with the highest average high temperature) is July (91°F).
The month with the lowest average high temperature is January (55.4°F).
- Average low temperature in September: 68.2°F
The month with the highest average low temperature is July (73.2°F).
The coldest month (with the lowest average low temperature) is January (39.9°F).
Average pressure in September
Fairfax, SC
- Average pressure in September: 30"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.97"Hg).
Average wind speed in September
Fairfax, SC
- 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
Fairfax, SC
- Average humidity in September: 75%
The months with the highest relative humidity are August and December (76%).
The month with the lowest relative humidity is January (70%).
Average rainfall in September
Fairfax, SC
- Average rainfall in September: 1.97"
The wettest month (with the highest rainfall) is August (3.7").
The driest month (with the least rainfall) is November (1.38").
Average rainfall days in September
Fairfax, SC
- Average rainfall days in September: 13.9 days
The month with the highest number of rainy days is August (20.8 days).
The month with the least rainy days is November (6.6 days).
Average snowfall in September
Fairfax, SC
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.12").
The months with the least snowfall are March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Fairfax, SC
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (0.3 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Fairfax, SC
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in September: 8h and 2min
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
Fairfax, SC
- Average sunshine days in September: 14.3 days
The month with the most sunshine days is November (22.3 days).
The month with the least sunshine days is August (7.3 days).
Average UV index in September
Fairfax, SC
- Average UV index in September: 6
The months with the highest UV index are June, July and August (UV index 7).
The months with the lowest UV index are January and December (UV index 3).
Average cloud cover in September
Fairfax, SC
- Average cloud cover in September: 33
The months with the most cloud cover are February and December (Cloud cover 43).
The month with the least cloud cover is October (Cloud cover 29).
Average visibility in September
Fairfax, SC
- 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).
Fairfax, South Carolina, USA
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