September weather forecast
Tyler, TX

September in Tyler, Texas unravels a subtle transition from hot summer days to cooler autumn evenings. While Sunshine hours decrease, marching towards fall, September retains traces of warmth from the outgoing summer. The lift in precipitation levels brings along more humid days, hence resulting in a somewhat dank atmosphere. The weather phenomenon in September serves as a precursor to the cooler days of October.

Temperature

In September, the average high-temperature marginally drops from a very hot 95°F (35°C) in August to a tropical 88.2°F (31.2°C). The nighttime temperature dips to a refreshing 67.6°F (19.8°C) on average during September.

Heat index

September's mean heat index is appraised at a torrid 100.4°F (38°C). Heightened safety actions are necessary, heat cramps and heat exhaustion are probable. Persistent activity may lead to heatstroke.
It is important to note that the heat index values are for shaded areas and light wind scenarios. 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 'feels like' or 'apparent temperature', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. Additional elements encompassing metabolic differences, the degree of physical activity, and attire can impact the individual's perception of temperature. Direct sunlight exposure should be noted as it has the potential to increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Young ones are generally at greater risk than adults due to their limited sweating ability. In addition, their large skin surface relative to their small bodies and higher heat production from their activities add to their vulnerability.
The human body cools itself through perspiration, as excessive warmth is removed from the body through sweat evaporation. An elevated level of relative humidity hinders evaporation, leading to decreased heat elimination from the body, inducing a sensation of excess heat. If heat absorption isn't effectively countered by the body's cooling methods, body temperature surges, hinting at potential problems.

Humidity

In Tyler, the average relative humidity in September is 69%.

Rainfall

In Tyler, in September, it is raining for 14.1 days, with typically 1.61" (41mm) of accumulated precipitation. Throughout the year, there are 143.4 rainfall days, and 25.75" (654mm) of precipitation is accumulated.

Snowfall

April through October and December are months without snowfall.

Daylight

In Tyler, the average length of the day in September is 12h and 21min.
On the first day of September, sunrise is at 6:56 am and sunset at 7:45 pm. On the last day of the month, sunrise is at 7:15 am and sunset at 7:06 pm CDT.

Sunshine

In September, the average sunshine in Tyler is 8.8h.

UV index

In Tyler, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high threat to health from unprotected exposure to Sun's UV rays for the average person.
Note: The UV index of 6 during September translates into the following guidance:
Follow precautions and abide by sun safety rules. Deterrence of sunburn is imperative. The Sun's UV radiation is at its strongest between the hours of 10 a.m. and 4 p.m. Minimize direct exposure to the sun during this period. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays. Take heed! The reflection of snow can intensify the Sun's UV radiation nearly double.