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
September's average high-temperature stands at a moderately hot 82.6°F (28.1°C), showing little deviation from August's 87.8°F (31°C). Nighttime temperatures in September average to a comfortable 65.1°F (18.4°C).Heat index
The heat index for September is estimated at a hot 87.8°F (31°C). With extended exposure and activity, one might feel exhausted and experience heat cramps.The standards for the heat index are set for locations in shade and under light breezes. The heat index may experience an enhancement of 15 Fahrenheit (8 Celsius) degrees under direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'real feel', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. A person's impression of weather can be shaped by several aspects, among them metabolic variations, pregnancy, and levels of physical activity. It is essential to be conscious of the fact that direct sunlight can intensify the felt heat, leading to an elevation in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly meaningful for babies and toddlers. Children frequently underestimate the necessity to rest and hydrate. Thirst is a late sign of dehydration - thus, it is vital to stay hydrated, particularly during lengthy physical exercises.
Humidity
In September, the average relative humidity is 74%.Rainfall
In Jefferson, during September, the rain falls for 13.4 days and regularly aggregates up to 2.68" (68mm) of precipitation. In Jefferson, during the entire year, the rain falls for 166.4 days and collects up to 33.7" (856mm) of precipitation.Snowfall
April through October are months without snowfall in Jefferson.Daylight
In Jefferson, the average length of the day in September is 12h and 23min.On the first day of the month, sunrise is at 6:55 am and sunset at 7:47 pm. On the last day of September, in Jefferson, sunrise is at 7:15 am and sunset at 7:06 pm EDT.
Sunshine
In Jefferson, the average sunshine in September is 9.1h.UV index
In September, the average daily maximum UV index is 6. A UV Index reading of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: A maximum daily UV index of 6 during September morphs into the following directions:
Prevent overexposure. Protection from the sun's harmful effects is needed. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. 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 is September in Jefferson?
What is the average humidity in September in Jefferson?
How many days does it rain in September in Jefferson?
When it does not snow in Jefferson?
How many hours of daylight does Jefferson have in September?
When are sunrise and sunset in September in Jefferson?
How many hours of sunshine does Jefferson have in September?
How high is the UV index in September in Jefferson?
Average temperature in September
Jefferson, SC
- Average high temperature in September: 82.6°F
The warmest month (with the highest average high temperature) is July (90.1°F).
The month with the lowest average high temperature is January (50.2°F).
- Average low temperature in September: 65.1°F
The month with the highest average low temperature is July (72°F).
The coldest month (with the lowest average low temperature) is January (35.2°F).
Average pressure in September
Jefferson, SC
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is November (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.97"Hg).
Average wind speed in September
Jefferson, SC
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is April (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
Jefferson, SC
- Average humidity in September: 74%
The months with the highest relative humidity are May and December (75%).
The months with the lowest relative humidity are January, March, July and November (71%).
Average rainfall in September
Jefferson, SC
- Average rainfall in September: 2.68"
The wettest month (with the highest rainfall) is August (3.54").
The driest month (with the least rainfall) is October (2.17").
Average rainfall days in September
Jefferson, SC
- Average rainfall days in September: 13.4 days
The month with the highest number of rainy days is July (19 days).
The month with the least rainy days is October (9.5 days).
Average snowfall in September
Jefferson, SC
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.34").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Jefferson, SC
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (1.4 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
Jefferson, SC
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 9h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 30min).
Average sunshine days in September
Jefferson, SC
- Average sunshine days in September: 15 days
The month with the most sunshine days is October (20.4 days).
The month with the least sunshine days is July (9.7 days).
Average UV index in September
Jefferson, SC
- Average UV index in September: 6
The months with the highest UV index are June and July (UV index 7).
The month with the lowest UV index is January (UV index 2).
Average cloud cover in September
Jefferson, SC
- Average cloud cover in September: 31
The months with the most cloud cover are February, March and December (Cloud cover 41).
The month with the least cloud cover is June (Cloud cover 28).
Average visibility in September
Jefferson, 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).
Jefferson, South Carolina, USA
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