September weather forecastBellaire, TX
September
Weather in September
September, the first month of the autumn in Bellaire, is still a hot month, with an average temperature varying between 72.7°F (22.6°C) and 88.3°F (31.3°C).Temperature
The arrival of September correlates with a minor temperature reduction, down from August's hot 94.3°F (34.6°C) to a still tropical 88.3°F (31.3°C). An average nighttime temperature of 72.7°F (22.6°C) is witnessed throughout September.Heat index
For September, the heat index is estimated at a scorching 104°F (40°C). Incorporate additional preventive steps, heat exhaustion and heat cramps are possible. Long-lasting activity may cause heatstroke.Observations indicate that the heat index values are for shady locations with light wind. If exposed to direct sunlight, the heat index could climb by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'feels like', is an amalgamation of air temperature and humidity to express the equivalent perceived temperature. One's perception of temperature can vary depending on physical activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. 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 highly important for children. Young children typically face greater hazards than adults because they do not sweat as much. Their larger skin surface in comparison to their little bodies and the high heat production from their active nature compounds their vulnerability.
Perspiration and the resultant sweat evaporation are the body's natural thermostat, helping regulate temperature. When relative humidity is heightened, it slows the rate of evaporation, thereby decreasing the body's ability to shed heat and creating a sensation of overheating. Temperature imbalances caused by excessive heat retention can trigger heat-related maladies.
Humidity
In Bellaire, the average relative humidity in September is 74%.Rainfall
September is the month with the most rainfall. Rain falls for 19.5 days and accumulates 4.49" (114mm) of precipitation.Snowfall
February through November are months without snowfall.Daylight
In September, the average length of the day is 12h and 20min.On the first day of the month, sunrise is at 6:59 am and sunset at 7:43 pm. On the last day of September, sunrise is at 7:14 am and sunset at 7:08 pm CDT.
Sunshine
In September, the average sunshine is 8.6h.UV index
In September, the average daily maximum UV index is 6. A UV Index estimate of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for average individuals.Note: In September, a daily UV index of 6 turns into the following recommendations:
Deflect overexposure. Sun protection is a necessity. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Bellaire, TX
- Average high temperature in September: 88.3°F
The warmest month (with the highest average high temperature) is August (94.3°F).
The month with the lowest average high temperature is January (61.3°F).
- Average low temperature in September: 72.7°F
The month with the highest average low temperature is August (77.5°F).
The coldest month (with the lowest average low temperature) is January (46°F).
Average pressure in September
Bellaire, 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
Bellaire, TX
- Average wind speed in September: 5.9mph
The windiest month (with the highest average wind speed) is April (8.6mph).
The calmest month (with the lowest average wind speed) is September (5.9mph).
Average humidity in September
Bellaire, TX
- Average humidity in September: 74%
The month with the highest relative humidity is February (78%).
The months with the lowest relative humidity are August and October (70%).
Average rainfall in September
Bellaire, TX
- Average rainfall in September: 4.49"
The wettest month (with the highest rainfall) is September (4.49").
The driest month (with the least rainfall) is February (1.77").
Average rainfall days in September
Bellaire, TX
- Average rainfall days in September: 19.5 days
The month with the highest number of rainy days is September (19.5 days).
The month with the least rainy days is January (11.8 days).
Average snowfall in September
Bellaire, TX
- Average snowfall in September: 0"
The month with the highest snowfall is December (0.08").
The months with the least snowfall are February, March, April, May, June, July, August, September, October and November (0").
Average snowfall days in September
Bellaire, TX
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and December (0.1 days).
The months with the least snowfall days are February, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Bellaire, 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 month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is December (Average sunshine: 4h and 48min).
Average sunshine days in September
Bellaire, TX
- Average sunshine days in September: 7.9 days
The month with the most sunshine days is January (16.3 days).
The month with the least sunshine days is September (7.9 days).
Average UV index in September
Bellaire, 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
Bellaire, TX
- Average cloud cover in September: 32
The month with the most cloud cover is February (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Bellaire, 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).





