September weather forecastJohnson City, TX
September
Weather in September
The first month of the autumn, September, is still a tropical month in Johnson City, Texas, with an average temperature fluctuating between 86.4°F (30.2°C) and 68.4°F (20.2°C).Temperature
The move into September indicates a slight reduction in the average high-temperature, down from August's tropical 93.9°F (34.4°C) to a still hot 86.4°F (30.2°C). In Johnson City, the September nights cool down to an average low of 68.4°F (20.2°C).Heat index
September's heat index is evaluated at a very hot 96.8°F (36°C). Ensure extra safety measures, heat exhaustion and heat cramps are likely. Continuous activity might result in heatstroke.Heat index readings emphasize conditions of light breezes and shaded spots. With direct sunlight, the heat index could increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', integrates the air's temperature and its humidity to showcase the felt temperature by people. An individual's temperature experience can be influenced by extra factors, including metabolic differences, activity levels, and clothing. When directly under the sun, the weather's impact can intensify, possibly boosting the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are largely significant for babies and toddlers. Young individuals usually face greater risks than adults as their sweat production is less. Also, their larger skin surface relative to their small bodies and the high heat generation due to their activity contributes to their vulnerability.
In the face of high temperatures, the human body's reflex is to perspire, leveraging sweat evaporation for cooling. Greater relative humidity lessens the rate of evaporation, thus decreasing the body's heat dispersal, which gives rise to a sensation of overheating. Overheating dangers loom when the body's heat release mechanisms are overshadowed by excessive gain.
Humidity
The average relative humidity in September is 70%.Rainfall
In Johnson City, during September, the rain falls for 16.4 days and regularly aggregates up to 3.31" (84mm) of precipitation. Throughout the year, there are 149 rainfall days, and 24.92" (633mm) of precipitation is accumulated.Snowfall
In Johnson City, snow does not fall in March through October and December.Daylight
The average length of the day in September is 12h and 20min.On the first day of the month, sunrise is at 7:10 am and sunset at 7:55 pm. On the last day of September, sunrise is at 7:26 am and sunset at 7:19 pm CDT.
Sunshine
The average sunshine in September is 8.3h.UV index
In Johnson City, Texas, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV rays for the average person.Note: In September, the UV index of 6 transforms into the following advice:
Refrain from overexposure. Fair-skinned individuals could burn in under 20 minutes. The Sun's UV radiation is most intense from 10 a.m. to 4 p.m. Try to avoid direct sun exposure during these hours. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Johnson City, TX
- Average high temperature in September: 86.4°F
The warmest month (with the highest average high temperature) is August (93.9°F).
The month with the lowest average high temperature is January (58.6°F).
- Average low temperature in September: 68.4°F
The month with the highest average low temperature is August (72.9°F).
The coldest month (with the lowest average low temperature) is January (41.4°F).
Average pressure in September
Johnson City, TX
- Average pressure in September: 29.95"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Johnson City, TX
- Average wind speed in September: 6.6mph
The windiest month (with the highest average wind speed) is March (10.1mph).
The calmest month (with the lowest average wind speed) is September (6.6mph).
Average humidity in September
Johnson City, TX
- Average humidity in September: 70%
The month with the highest relative humidity is May (76%).
The month with the lowest relative humidity is August (61%).
Average rainfall in September
Johnson City, TX
- Average rainfall in September: 3.31"
The wettest month (with the highest rainfall) is May (4.13").
The driest month (with the least rainfall) is February (1.18").
Average rainfall days in September
Johnson City, TX
- Average rainfall days in September: 16.4 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (8.9 days).
Average snowfall in September
Johnson City, TX
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.2").
The months with the least snowfall are March, April, May, June, July, August, September, October and December (0").
Average snowfall days in September
Johnson City, TX
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.7 days).
The months with the least snowfall days are March, April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Johnson City, TX
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 14h and 6min).
The month with the shortest days is December (Average daylight: 10h and 12min).
- Average sunshine in September: 8h and 18min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The months with the least sunshine are November and December (Average sunshine: 5h and 30min).
Average sunshine days in September
Johnson City, TX
- Average sunshine days in September: 11.1 days
The month with the most sunshine days is January (21.1 days).
The months with the least sunshine days are May and September (11.1 days).
Average UV index in September
Johnson City, TX
- Average UV index in September: 6
The months with the highest UV index are June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
Johnson City, TX
- Average cloud cover in September: 35
The month with the most cloud cover is May (Cloud cover 46).
The month with the least cloud cover is August (Cloud cover 24).
Average visibility in September
Johnson City, TX
- 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).
