September weather forecastWillis, TX
September
Weather in September
The first month of the autumn, September, is also a hot month in Willis, Texas, with temperature in the range of an average high of 89.1°F (31.7°C) and an average low of 70.7°F (21.5°C).Temperature
September sees a slight reduction in average high-temperature, with a shift from a sweltering 95.5°F (35.3°C) in August to a hot 89.1°F (31.7°C). Throughout the September nights, Willis encounters a low-temperature of 70.7°F (21.5°C).Heat index
September's average heat index is evaluated at a blisteringly hot 105.8°F (41°C). Preventive measures are required to mitigate the risk of heat cramps and heat exhaustion. Continuous activity may precipitate heatstroke.Understanding the heat index involves considering values for shaded locales with light wind. Direct sunlight exposure may result in a rise of the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', quantifies the warmth felt when relative humidity is considered. The impact of weather on an individual can be subjective, affected by the person's activity and heat perception, which can vary due to elements including wind, clothing, and metabolic differences. It is essential to realize that direct sunlight can escalate the perceived temperature, increasing the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are largely significant for babies and toddlers. Young ones often ignore the need to take a break and drink fluids. Thirst is a late-stage symptom of dehydration - hence, maintaining hydration, particularly during extended physical activities, is crucial.
Evaporating sweat is a key way the human body dispels excessive warmth, all thanks to the process of perspiration. In the presence of elevated relative humidity, the evaporation rate decreases. This reduction leads to increased body heat retention compared to conditions of dry air. Inadequate heat shedding in the face of rising body temperatures hints at potential dehydration risks.
Humidity
In Willis, the average relative humidity in September is 74%.Rainfall
In Willis, during September, the rain falls for 18.2 days and regularly aggregates up to 3.5" (89mm) of precipitation. Throughout the year, in Willis, there are 176.1 rainfall days, and 34.33" (872mm) of precipitation is accumulated.Snowfall
In Willis, snow does not fall in February through November.Daylight
The average length of the day in September in Willis is 12h and 20min.On the first day of September, sunrise is at 6:59 am and sunset at 7:44 pm. On the last day of the month, sunrise is at 7:15 am and sunset at 7:08 pm CDT.
Sunshine
In Willis, the average sunshine in September is 8.6h.UV index
In September, the average daily maximum UV index in Willis is 6. A UV Index reading of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: The daily high UV index of 6 in September translates into this advice:
Skirt overexposure. People with light complexions might get scorched in under 20 minutes. Avoid exposure to the Sun and try to stay in the shade between 10 a.m. and 4 p.m., when UV radiation is most potent, but be aware that parasols or canopies may not offer full protection. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Willis, TX
- Average high temperature in September: 89.1°F
The warmest month (with the highest average high temperature) is August (95.5°F).
The month with the lowest average high temperature is January (59.2°F).
- Average low temperature in September: 70.7°F
The months with the highest average low temperature are July and August (74.8°F).
The coldest month (with the lowest average low temperature) is January (42.8°F).
Average pressure in September
Willis, 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
Willis, TX
- Average wind speed in September: 5.1mph
The windiest month (with the highest average wind speed) is April (7.3mph).
The calmest month (with the lowest average wind speed) is September (5.1mph).
Average humidity in September
Willis, TX
- Average humidity in September: 74%
The month with the highest relative humidity is February (80%).
The month with the lowest relative humidity is August (69%).
Average rainfall in September
Willis, TX
- Average rainfall in September: 3.5"
The wettest month (with the highest rainfall) is May (4.02").
The driest month (with the least rainfall) is November (1.97").
Average rainfall days in September
Willis, TX
- Average rainfall days in September: 18.2 days
The month with the highest number of rainy days is September (18.2 days).
The months with the least rainy days are January and October (12.1 days).
Average snowfall in September
Willis, TX
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.16").
The months with the least snowfall are February, March, April, May, June, July, August, September, October and November (0").
Average snowfall days in September
Willis, TX
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (0.3 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Willis, 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 36min
The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is December (Average sunshine: 4h and 54min).
Average sunshine days in September
Willis, TX
- Average sunshine days in September: 9.9 days
The months with the most sunshine days are January and October (16.6 days).
The month with the least sunshine days is September (9.9 days).
Average UV index in September
Willis, 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
Willis, TX
- Average cloud cover in September: 35
The month with the most cloud cover is February (Cloud cover 53).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in September
Willis, TX
- Average visibility in September: 5mi
The months with the highest visibility are January, August and October (6mi).
The months with the lowest visibility are February, March, April, May, June, July, September, November and December (5mi).





