San Antonio Weather in September: Temperature, Precipitation, Wind

Temperature
30.1°C
86.2°F
High temperature
36.7°C
98°F
Low temperature
24.4°C
75.9°F
Feels like
31.3°C
88.4°F
Rainy days
6 days
Rainfall level
0.52mm
0.02 inch
Cloud coverage
29.5%
Wind speed
23.6km/h
14.6mph
Daylight time
12:19:51
UV index
9
1
clear day
30.9°C
88.0°F
2
clear day
30.9°C
88.0°F
3
clear day
30.8°C
87.0°F
4
partly cloudy day
31.8°C
89.0°F
5
partly cloudy day
32.2°C
90.0°F
6
partly cloudy day
31.7°C
89.0°F
7
partly cloudy day
32.4°C
90.0°F
8
clear day
32.7°C
91.0°F
9
rain
31.4°C
89.0°F
10
rain
30.4°C
87.0°F
11
partly cloudy day
30.4°C
87.0°F
12
partly cloudy day
29.4°C
85.0°F
13
partly cloudy day
28.8°C
84.0°F
14
rain
29.6°C
85.0°F
15
rain
28.1°C
83.0°F
16
partly cloudy day
28.4°C
83.0°F
17
clear day
28.2°C
83.0°F
18
partly cloudy day
29.3°C
85.0°F
19
clear day
29.1°C
84.0°F
20
clear day
29.4°C
85.0°F
21
partly cloudy day
30.0°C
86.0°F
22
partly cloudy day
30.2°C
86.0°F
23
partly cloudy day
31.1°C
88.0°F
24
partly cloudy day
31.4°C
89.0°F
25
rain
30.4°C
87.0°F
26
rain
29.1°C
84.0°F
27
partly cloudy day
28.9°C
84.0°F
28
partly cloudy day
29.1°C
84.0°F
29
clear day
28.7°C
84.0°F
30
partly cloudy day
28.9°C
84.0°F

San Antonio, Texas experiences warm and dry conditions in September, marking the transition from summer to fall. The average temperature hovers around 30.1°C (86.2°F), with daytime highs reaching a sweltering 36.7°C (98.0°F) and nighttime lows dipping to 24.4°C (75.9°F). Heat indices push the perceived temperature even higher, with the average maximum feeling like 37.6°C (99.7°F).

Humidity levels in San Antonio during September average 56.7%, contributing to the muggy feel despite the relatively low precipitation. The city receives an average of 13.2 mm (0.52 inches) of rain throughout the month, with only 6 rainy days expected. Precipitation probability stands at 20%, and rain is the predominant form of precipitation.

Cloud cover is moderate, averaging 29.5%, allowing for ample sunshine. The UV index remains high at 9, necessitating sun protection for outdoor activities. Visitors to popular attractions like the River Walk or the Alamo should be prepared for intense sunlight.

Wind speeds average 23.6 km/h (14.7 mph), with gusts reaching up to 40.6 km/h (25.2 mph). These breezes provide some relief from the heat but can contribute to fire danger, as evidenced by the elevated severe risk of 39.7%.

Atmospheric pressure averages 1012.3 hPa, typical for the region. Visibility is excellent at 16.0 km (9.9 miles), offering clear views of the city skyline and surrounding Hill Country.

Daylight hours begin to shorten in September, with sunrise occurring around 7:18 AM and sunset at approximately 7:38 PM. The long days provide ample time for outdoor activities in San Antonio’s numerous parks and historical sites.

What is the temperature in San Antonio in September?

Average air temperature in San Antonio is 30.1°C (86.2°F) in September. The outside temperature in San Antonio feels like 31.3°C (88.4°F) on a typical September day. The highest average temperature during sunny days is 36.7°C (98°F) and feels like 37.6°C (99.7°F). The lowest average temperature after dark is 24.4°C (75.9°F) which feels like 24.5°C (76°F).

Daily Temperature in San Antonio in September 0°C / 32.0°F 10°C / 50.0°F 20°C / 68.0°F 30°C / 86.0°F 40°C / 104.0°F 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

How hot is San Antonio in September?

The hot temperature in September in San Antonio rises to 40°C (104°F) on sunny days with low cloud coverage and 56.7% humidity. During hottest days of September it feels like 41.7 °C (107.1°F). The average maximum temp in San Antonio is 36.7°C (107.1°F) during day time in September.

How cold is San Antonio in September?

The coldest temp in San Antonio in September drops to 21.5°C (70.7°F) during the cold nights. With 23.6km/h (14.6mph) winds and 56.7% humidity it feels like 21.5°C (70.7°F) on the coldest nights. The average minimum temperature is 24.4°C (75.9°F) during night time in September.

Does it rain in San Antonio in September?

Yes, it rains for 6 days in San Antonio, United States in September averaging 0.52 mm of precipitation. San Antonio has a 20% chance for rain throughout the entire month of September.

How much does it rain in San Antonio throughout September?

San Antonio has 0.52 mm (0.02 inch) of rain per day on average in September. It rains for an average of 6 days out of the entire month.

Is San Antonio windy in September?

The average speed of wind in San Antonio, United States during September is 23.6km/h (14.6mph) and average windgust is 40.6km/h (25.2mph). On some days in September wind can reach up to 32.4km/h (20.1mph).

Daily wind speed in San Antonio in September 0km/h (0mph) 9km/h (6mph) 18km/h (11mph) 27km/h (17mph) 36km/h (22mph) 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

What is the direction of the wind in San Antonio in September?

Most days of September the wind is blowing from East-Southeast direction in San Antonio.

What are the humidity levels in San Antonio in September?

The average humidity levels in San Antonio in September are 56.7%. Daily humidity levels in San Antonio range from 44.5% to 66.6% during September.

Daily humidity levels in San Antonio in September 0% 17% 34% 51% 68% 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

How many hours of daylight are in San Antonio in September?

San Antonio has 12 hours 19 minutes of daylight in September on average. Sunset and sunrise times gradually change throughout the month. Sunrise in San Antonio in September is at 7:18:54 and the sunset is at 19:38:45.

What is the cloud coverage in San Antonio in September?

Clouds cover 29.5% of the sky on average throughout September in San Antonio. The cloud coverage ranges from 2.6% to 60.9% depending on the day of the month.

What is the UV level in September in San Antonio?

The average UV index in San Antonio is 9 in September. UV levels change throughout the month and range from 7 to 10.

What is the solar radiation in San Antonio in September?

The average solar radiation is 237.4 W/m2 (Watts per square meter) in San Antonio during September. However solar radiation levels change throughout the month and range from 141.8 W/m2 to 287.9 W/m2.

What is the solar energy during September in San Antonio?

The average solar energy during September in San Antonio is 20.5 MJ/m2 (megajoules per square metre). Solar energy ranges from 12.3 MJ/m2, to 24.8 MJ/m2 during September.

Are there severe weather risks in San Antonio in September?

Yes, there is a 39.7% risk for severe weather in San Antonio, United States in September.

What is the air pressure in San Antonio in September?

On average the air pressure in San Antonio in September is 1012.3 mb (millibars). Throughout the month the sea level pressure ranges from 1008.9 mb to 1015.5 mb.

What is the visibility in San Antonio in September?

The average daylight visibility in San Antonio in September is 16 km (9.9 miles). Depending on the precipitation the visibility ranges from 15.6 km (9.7 miles) to 16 km (9.9 miles) throughout September.

What is the dew point in San Antonio in September?

The average dew point in San Antonio during September is 19.5°C (67°F).

Where is the data for San Antonio climate in September coming from?

The climate data for San Antonio, Texas, United States in September is collected from the following weather stations.

  • SAN ANTONIO STINSON MUNICIPAL AIRPORT, TX US
  • SAN ANTONIO INTERNATIONAL AIRPORT, TX US
  • SAN ANTONIO KELLY FIELD AFB, TX US
  • FW6098 San Antonio TX US
  • FW8761 San Antonio TX US
  • KSAT
  • KSKF
  • KSSF