Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
In September, the average high-temperature in Richardson marginally drops from a very hot 95.7°F (35.4°C) in August to a hot 87.6°F (30.9°C). An average temperature of 70.2°F (21.2°C) marks the nights in September.Heat index
The heat index for September is calculated to be a fiery hot 95°F (35°C). Incorporate additional preventive steps, heat exhaustion and heat cramps are possible. Long-lasting activity may cause heatstroke.Heat index guidelines indicate values are for light wind scenarios and shaded regions. Exposure to the sun directly might heighten the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', shows a temperature sensation when both heat and moisture conditions are combined. Elements such as metabolic variations, being pregnant, and physical activity can impact one's weather perception. In the direct sunlight, the weather's impact can be amplified, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. Children often fail to understand the importance of rest and rehydration. Thirst is a late manifestation of dehydration - hence, it is crucial to stay hydrated, especially during ongoing physical activities.
Perspiring is how the human body naturally cools down, as sweat's evaporation takes away excess heat. Increased relative humidity interferes with body cooling by slowing the rate of evaporation, resulting in a slower body cooling rate and a heightened feeling of heat. When body temperature rises due to an imbalance in heat gain, there's a potential for dehydration and overheating.
Humidity
The average relative humidity in September in Richardson is 63%.Rainfall
In Richardson, in September, during 13.1 rainfall days, 1.06" (27mm) of precipitation is typically accumulated. In Richardson, during the entire year, the rain falls for 118.4 days and collects up to 15.51" (394mm) of precipitation.Snowfall
March through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 22min.On the first day of the month, sunrise is at 7:01 am and sunset at 7:51 pm. On the last day of September, sunrise is at 7:20 am and sunset at 7:12 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 of 6 to 7 symbolizes a high health risk from unsafe exposure to UV radiation for the average person.Note: The maximum UV index of 6 during September leads to these instructions:
Enforce precautions and stick to sun safety measures. Preservation from skin and eye damage is essential. Between 10 a.m. and 4 p.m., UV radiation is strongest. Make an effort to avoid direct sunlight during this time, remembering that shade structures may not provide full sun protection. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Is it hot during September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Richardson, TX
- Average high temperature in September: 87.6°F
The warmest month (with the highest average high temperature) is August (95.7°F).
The month with the lowest average high temperature is January (54°F).
- Average low temperature in September: 70.2°F
The month with the highest average low temperature is August (76.5°F).
The coldest month (with the lowest average low temperature) is January (38.7°F).
Average pressure in September
Richardson, TX
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Richardson, TX
- Average wind speed in September: 6.7mph
The windiest months (with the highest average wind speed) are March and April (9.9mph).
The calmest month (with the lowest average wind speed) is September (6.7mph).
Average humidity in September
Richardson, TX
- Average humidity in September: 63%
The month with the highest relative humidity is May (73%).
The month with the lowest relative humidity is August (56%).
Average rainfall in September
Richardson, TX
- Average rainfall in September: 1.06"
The wettest month (with the highest rainfall) is May (1.97").
The driest month (with the least rainfall) is February (0.75").
Average rainfall days in September
Richardson, TX
- Average rainfall days in September: 13.1 days
The month with the highest number of rainy days is September (13.1 days).
The month with the least rainy days is January (5.4 days).
Average snowfall in September
Richardson, TX
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.31").
The months with the least snowfall are March, April, May, June, July, August, September and October (0").
Average snowfall days in September
Richardson, TX
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (1.3 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Richardson, TX
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is August (Average sunshine: 11h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 36min).
Average sunshine days in September
Richardson, TX
- Average sunshine days in September: 14.5 days
The month with the most sunshine days is January (23.7 days).
The month with the least sunshine days is September (14.5 days).
Average UV index in September
Richardson, TX
- Average UV index in September: 6
The months with the highest UV index are May, June, July and August (UV index 7).
The months with the lowest UV index are January and December (UV index 3).
Average cloud cover in September
Richardson, TX
- Average cloud cover in September: 28
The months with the most cloud cover are February and March (Cloud cover 41).
The month with the least cloud cover is August (Cloud cover 20).
Average visibility in September
Richardson, 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).
Richardson, Texas, USA
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