September weather forecastFriendswood, TX
September
Weather in September
The first month of the autumn, September, is also a hot month in Friendswood, Texas, with temperature in the range of an average high of 86.2°F (30.1°C) and an average low of 75.7°F (24.3°C).Temperature
With September's advent, Friendswood sees an average high-temperature of a still tropical 86.2°F (30.1°C), subtly shifted from August's 90.5°F (32.5°C). An average temperature of 75.7°F (24.3°C) marks the nights in September.Heat index
September's average heat index is appraised at a very hot 98.6°F (37°C). Incorporate special precautions, risk of heat exhaustion and heat cramps is substantial. Sustained activity could cause heatstroke.It is crucial to understand that heat index figures are for shade and gentle wind conditions. The heat index values could be amplified by up to 15 Fahrenheit (8 Celsius) degrees in direct sunlight.
Note: The heat index, also known as 'real feel' or 'felt air temperature', stands as a testimony to how temperature and humidity combine to impact our sense of warmth. A person's impression of weather can be shaped by many aspects, among them metabolic variations, pregnancy, and levels of physical activity. Recognize that direct exposure to the sun can escalate the heat effect, potentially adding 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are quite important for children. Children often overlook the necessity for resting and fluid replenishment. Thirst is a late sign of dehydration - thus, it is critical to stay hydrated, especially during extended periods of physical activities.
In the face of high temperatures, the human body's reflex is to perspire, leveraging sweat evaporation for cooling. With a lot of moisture in the air, the evaporation process is not as effective, and the body does not cool down as efficiently, creating a perception of overheating. Exceeding the body's heat disposal threshold results in a rise in body temperature and potential thermal disorders.
Humidity
In September, the average relative humidity is 75%.Rainfall
September is the month with the most rainfall. Rain falls for 15.9 days and accumulates 1.5" (38mm) of precipitation.Snowfall
Months with snowfall are January, September and December. The months with the most snowfall days are January, September and December, with an average of 0.1 snowfall days.Daylight
In September, the average length of the day in Friendswood is 12h and 20min.On the first day of the month, sunrise is at 6:58 am and sunset at 7:42 pm. On the last day of September, sunrise is at 7:13 am and sunset at 7:07 pm CDT.
Sunshine
In September, the average sunshine is 8.6h.UV index
In Friendswood, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: The daily maximum UV index of 6 in September interprets into the following advice:
Ward off overexposure. Defence against solar harm is crucial. 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. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation. Attention! Nearly twice the Sun's UV radiation can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Friendswood, TX
- Average high temperature in September: 86.2°F
The warmest month (with the highest average high temperature) is August (90.5°F).
The month with the lowest average high temperature is January (60.4°F).
- Average low temperature in September: 75.7°F
The month with the highest average low temperature is August (79.7°F).
The coldest month (with the lowest average low temperature) is January (48.6°F).
Average pressure in September
Friendswood, TX
- Average pressure in September: 29.96"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
Friendswood, TX
- Average wind speed in September: 7.7mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest month (with the lowest average wind speed) is August (7.6mph).
Average humidity in September
Friendswood, TX
- Average humidity in September: 75%
The month with the highest relative humidity is February (80%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Friendswood, TX
- Average rainfall in September: 1.5"
The wettest month (with the highest rainfall) is September (1.5").
The driest months (with the least rainfall) are February and March (0.31").
Average rainfall days in September
Friendswood, TX
- Average rainfall days in September: 15.9 days
The month with the highest number of rainy days is September (15.9 days).
The month with the least rainy days is February (6.3 days).
Average snowfall days in September
Friendswood, TX
- Average snowfall days in September: 0.1 days
The months with the highest number of snowfall days are January, September and December (0.1 days).
The months with the least snowfall days are February, March, April, May, June, July, August, October and November (0 days).
Average daylight in September /
Average sunshine in September
Friendswood, TX
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 14h and 0min).
The month with the shortest days is December (Average daylight: 10h and 18min).
- Average sunshine in September: 8h and 36min
The months with the most sunshine are July and August (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 4h and 42min).
Average sunshine days in September
Friendswood, TX
- Average sunshine days in September: 10.3 days
The month with the most sunshine days is January (21.9 days).
The month with the least sunshine days is September (10.3 days).
Average UV index in September
Friendswood, TX
- 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 December (UV index 3).
Average cloud cover in September
Friendswood, TX
- Average cloud cover in September: 31
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 26).
Average visibility in September
Friendswood, 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).





