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 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
As August turns into September, the average high-temperatures rest at a still tropical 88.2°F (31.2°C), showing a minor variation from the prior month. In September, San Antonio experiences a temperature dip to an average of 73.8°F (23.2°C) at night.Heat index
During September, the heat index is calculated to be an extremely hot 105.8°F (41°C). Incorporate special precautions, risk of heat exhaustion and heat cramps is substantial. Sustained activity could cause heatstroke.One should consider that heat index numbers are for shaded settings and light wind. In the presence of direct sunshine, the heat index could be augmented by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. This effect is personal, shaped by the individual's physical activity and heat sensitivity, influenced by factors including wind, clothing, and metabolic variances. Realize that direct exposure to sunlight can augment the felt heat, leading to a potential increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to children. Children frequently do not understand the need for recuperation and hydration. Thirst, being a late manifestation of dehydration, underlines the need to hydrate frequently, especially when engaging in prolonged physical exercises.
The evaporation of sweat is a natural cooling mechanism of the human body, facilitated by perspiration. 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. Overheating and potential dehydration arise when body heat gain eclipses its release capability.
Humidity
The months with the highest humidity are August and September, with an average relative humidity of 79%.Rainfall
In San Antonio, in September, during 24.4 rainfall days, 4.45" (113mm) of precipitation is typically accumulated. In San Antonio, during the entire year, the rain falls for 200.6 days and collects up to 40.39" (1026mm) of precipitation.Snowfall
In San Antonio, snow does not fall in February through December.Daylight
The average length of the day in September is 12h and 19min.On the first day of September, sunrise is at 7:07 am and sunset at 7:49 pm. On the last day of the month, sunrise is at 7:21 am and sunset at 7:15 pm EDT.
Sunshine
The average sunshine in September is 8.9h.UV index
The months with the highest UV index are May through July and September, with an average maximum UV index of 7. A UV Index estimate of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum daily UV index of 7 during September translates into the following directions:
Adopt measures and apply sun safety strategies. Shielding from skin and eye damage is necessary. Limit direct sun exposure and seek shade between 10 a.m. and 4 p.m., the time of the most intense UV radiation, noting that shade structures may not provide total sun protection. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September in San Antonio?
What is the most humid month?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
How many hours of daylight does San Antonio have in September?
What time are sunrise and sunset in September?
How many hours of sunshine does San Antonio have in September?
What is the month with the highest UV index?
How high is the UV index in September?
Average temperature in September
San Antonio, FL
- Average high temperature in September: 88.2°F
The warmest month (with the highest average high temperature) is August (90.1°F).
The month with the lowest average high temperature is January (67.6°F).
- Average low temperature in September: 73.8°F
The month with the highest average low temperature is August (76.3°F).
The coldest month (with the lowest average low temperature) is January (50.2°F).
Average pressure in September
San Antonio, FL
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is September (29.96"Hg).
Average wind speed in September
San Antonio, FL
- Average wind speed in September: 4.9mph
The windiest months (with the highest average wind speed) are March and April (6.5mph).
The calmest month (with the lowest average wind speed) is July (4.5mph).
Average humidity in September
San Antonio, FL
- Average humidity in September: 79%
The months with the highest relative humidity are August and September (79%).
The month with the lowest relative humidity is March (72%).
Average rainfall in September
San Antonio, FL
- Average rainfall in September: 4.45"
The wettest month (with the highest rainfall) is August (7.17").
The driest months (with the least rainfall) are February, March and November (1.42").
Average rainfall days in September
San Antonio, FL
- Average rainfall days in September: 24.4 days
The month with the highest number of rainy days is August (28.8 days).
The month with the least rainy days is December (9.5 days).
Average snowfall days in September
San Antonio, FL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (0.1 days).
The months with the least snowfall days are February, March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
San Antonio, FL
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 13h and 54min).
The month with the shortest days is December (Average daylight: 10h and 24min).
- Average sunshine in September: 8h and 5min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is December (Average sunshine: 6h and 18min).
Average sunshine days in September
San Antonio, FL
- Average sunshine days in September: 3.8 days
The month with the most sunshine days is January (18.9 days).
The month with the least sunshine days is August (0.8 days).
Average UV index in September
San Antonio, FL
- Average UV index in September: 7
The months with the highest UV index are May, June, July and September (UV index 7).
The month with the lowest UV index is January (UV index 4).
Average cloud cover in September
San Antonio, FL
- Average cloud cover in September: 31
The months with the most cloud cover are February and December (Cloud cover 35).
The month with the least cloud cover is May (Cloud cover 27).
Average visibility in September
San Antonio, FL
- 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).
San Antonio, Florida, USA
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