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
During the shift to September, a minor reduction in average high-temperature is observed, shifting from 94.6°F (34.8°C) in August to a still tropical 88.3°F (31.3°C). During September, Jefferson sees a mean low-temperature of 67.1°F (19.5°C).Heat index
September's mean heat index is evaluated at a fiery hot 100.4°F (38°C). Use additional protective measures, heat cramps and heat exhaustion are possible outcomes. Continuous activity might lead to heatstroke.It is emphasized that the heat index's values are meant for shaded zones with mild winds. The heat index may experience an enhancement of 15 Fahrenheit (8 Celsius) degrees under direct sunlight.
Note: The heat index, also known as 'feels like' or 'real feel', is a composite of temperature and humidity figures to convey how warm it feels. Depending on the activity and the individual's heat perception, which may vary due to factors including wind, clothing, and metabolic variations, this effect remains subjective. 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 important for children. Children usually face more risks than adults as their ability to sweat is less. Additionally, their larger skin surface in relation to their petite bodies and higher heat output due to their activities increases their vulnerability.
To offset high temperatures, the human body releases sweat which, upon evaporation, cools it down. When the level of relative humidity is elevated, evaporation diminishes, causing more warmth to be retained in the body than in dry air. Heat disorders may be on the horizon when body temperatures rise from inadequate heat management.
Humidity
The average relative humidity in September is 69%.Rainfall
September is the month with the least rainfall. Rain falls for 13.6 days and accumulates 2.05" (52mm) of precipitation.Snowfall
In Jefferson, Texas, snow does not fall in April through December.Daylight
The average length of the day in September is 12h and 22min.On the first day of the month, sunrise is at 6:52 am and sunset at 7:41 pm. On the last day of September, sunrise is at 7:11 am and sunset at 7:02 pm CDT.
Sunshine
The average sunshine in September is 9.3h.UV index
The average daily maximum UV index in September is 6. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for average individuals.Note: The UV index of 6 in September translates into these instructions:
Persist in precautions and follow sun safety policies. Keeping sunburn at bay is imperative. Limit your direct sun exposure, especially between 10 a.m. and 4 p.m., when UV radiation is strongest. Shade structures might not provide complete sun protection. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What is the average humidity in September?
What is the driest month?
How much does it rain in September?
When it does not snow in Jefferson?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Jefferson, TX
- Average high temperature in September: 88.3°F
The warmest month (with the highest average high temperature) is July (94.8°F).
The month with the lowest average high temperature is January (54°F).
- Average low temperature in September: 67.1°F
The months with the highest average low temperature are July and August (73°F).
The coldest month (with the lowest average low temperature) is January (37.9°F).
Average pressure in September
Jefferson, TX
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Jefferson, TX
- Average wind speed in September: 5.2mph
The windiest month (with the highest average wind speed) is April (7.3mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
Jefferson, TX
- Average humidity in September: 69%
The month with the highest relative humidity is February (80%).
The month with the lowest relative humidity is August (67%).
Average rainfall in September
Jefferson, TX
- Average rainfall in September: 2.05"
The wettest month (with the highest rainfall) is April (4.41").
The driest month (with the least rainfall) is September (2.05").
Average rainfall days in September
Jefferson, TX
- Average rainfall days in September: 13.6 days
The month with the highest number of rainy days is August (14.8 days).
The month with the least rainy days is January (10.3 days).
Average snowfall in September
Jefferson, TX
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.63").
The months with the least snowfall are April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Jefferson, TX
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (1.1 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, TX
- 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: 9h and 2min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 5h and 6min).
Average sunshine days in September
Jefferson, TX
- Average sunshine days in September: 14.6 days
The month with the most sunshine days is October (18.9 days).
The month with the least sunshine days is February (12.8 days).
Average UV index in September
Jefferson, TX
- 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
Jefferson, TX
- Average cloud cover in September: 29
The month with the most cloud cover is February (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Jefferson, TX
- Average visibility in September: 6mi
The months with the highest visibility are January, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is February (5mi).
Jefferson, Texas, USA
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