September weather forecast
Helotes, TX

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Weather in September

The first month of the autumn, September, is still a tropical month in Helotes, Texas, with an average temperature ranging between max 88.2°F (31.2°C) and min 70.5°F (21.4°C).

Temperature

September brings a slight decrease in the average high-temperature, shifting from a torrid 95°F (35°C) in August to a tropical 88.2°F (31.2°C). Throughout the September nights, Helotes encounters a low-temperature of 70.5°F (21.4°C).

Heat index

The heat index value during September is estimated at a fiery hot 98.6°F (37°C). Adopt extra preventive measures, the occurrence of heat cramps and heat exhaustion is likely. Heatstroke may follow extended activity.
Understand that the heat index values take into account shaded locations and mild winds. 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 'real feel' or 'felt air temperature', is the result of factoring in humidity to the air temperature, indicating perceived warmth. The individual's impression of temperature can be affected by numerous factors such as metabolic variations, physical exertion, and attire. Do note, being directly under sun rays can amplify the heat you feel, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular importance for children. Kids generally face higher risks than adults as they sweat less. Along with their large skin surface compared to their small bodies and higher heat production due to their activities, their vulnerability is increased.
As a reaction to high temperatures, the human body begins to perspire, using the evaporation of sweat to lower its temperature. When the relative humidity is high, the evaporation rate is reduced. The warmth is removed from the body at a lower rate, causing the body to retain more heat than it would in dry air. Potential thermal conditions emerge as the body's heat gain outpaces its cooling mechanisms.

Humidity

The average relative humidity in September is 67%.

Rainfall

In Helotes, during September, the rain falls for 16.4 days and regularly aggregates up to 3.46" (88mm) of precipitation. Throughout the year, there are 140.3 rainfall days, and 23.15" (588mm) of precipitation is accumulated.

Snowfall

March through December 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 7:12 am and sunset at 7:56 pm. On the last day of September, sunrise is at 7:27 am and sunset at 7:21 pm CDT.

Sunshine

In September, the average sunshine is 8.5h.

UV index

In Helotes, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV rays for the ordinary person.
Note: An average maximum UV index of 6 in September leads to these recommendations:
Sustain precautions and conform to sun safety norms. Preventing sunburn is necessary. Stay out of direct sunlight between 10 a.m. and 4 p.m., when UV radiation is most intense, and remember that not all shade structures provide complete protection. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Updated: Aug 24, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

How hot is it in September?

The average high-temperature, in September, in Helotes, is 88.2°F (31.2°C), while the average low-temperature is 70.5°F (21.4°C). The average heat index (a.k.a. 'felt air temperature', 'feels like'), which takes the relative humidity and factors it into the air temperature reading, in September is estimated at 98.6°F (37°C).

What is the average humidity in September?

In Helotes, Texas, the average relative humidity in September is 67%.

How much does it rain in September?

In September, the rain falls for 16.4 days. Throughout September, 3.46" (88mm) of precipitation is accumulated.

When it does not snow?

In Helotes, Texas, snow does not fall in March through December.

How many hours of daylight does Helotes have in September?

In Helotes, Texas, the average day length in September is 12h and 20min.

What time are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 7:12 am and sunset at 7:56 pm. On the last day of the month, in Helotes, sunrise is at 7:27 am and sunset at 7:21 pm CDT.

How long on average sun shines in September in Helotes?

In Helotes, the average sunshine duration in September is 8.5h.

What is the UV index reading in September in Helotes?

In September, the average daily maximum UV index is 6. A UV Index of 6 to 7 symbolizes a high health threat from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Helotes, TX

Average temperature in September - Helotes, TX
  • Average high temperature in September: 88.2°F

The warmest month (with the highest average high temperature) is August (95°F).
The month with the lowest average high temperature is January (60.4°F).

  • Average low temperature in September: 70.5°F

The month with the highest average low temperature is August (74.5°F).
The coldest month (with the lowest average low temperature) is January (43.2°F).

Average pressure in September
Helotes, TX

Average pressure in September - Helotes, TX
  • Average pressure in September: 29.94"Hg

The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).

Average wind speed in September
Helotes, TX

Average wind speed in September - Helotes, TX
  • Average wind speed in September: 6.5mph

The windiest month (with the highest average wind speed) is April (9.1mph).
The calmest month (with the lowest average wind speed) is September (6.5mph).

Average humidity in September
Helotes, TX

Average humidity in September - Helotes, TX
  • Average humidity in September: 67%

The month with the highest relative humidity is May (74%).
The month with the lowest relative humidity is August (60%).

Average rainfall in September
Helotes, TX

Average rainfall in September - Helotes, TX
  • Average rainfall in September: 3.46"

The wettest month (with the highest rainfall) is May (3.74").
The driest month (with the least rainfall) is February (0.94").

Average rainfall days in September
Helotes, TX

Average rainfall days in September - Helotes, TX
  • Average rainfall days in September: 16.4 days

The month with the highest number of rainy days is May (16.6 days).
The month with the least rainy days is January (7.8 days).

Average snowfall in September
Helotes, TX

Average snowfall in September - Helotes, TX
  • Average snowfall in September: 0"

The months with the highest snowfall are January and February (0.08").
The months with the least snowfall are March, April, May, June, July, August, September, October, November and December (0").

Average snowfall days in September
Helotes, TX

Average snowfall days in September - Helotes, TX
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (0.5 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October and November (0 days).

Average daylight in September /
Average sunshine in September
Helotes, TX

Average daylight in September / Average sunshine in September - Helotes, TX
  • Average daylight in September: 12h and 2min

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 3min

The month with the most sunshine is July (Average sunshine: 10h and 12min).
The months with the least sunshine are November and December (Average sunshine: 5h and 30min).

Average sunshine days in September
Helotes, TX

Average sunshine days in September - Helotes, TX
  • Average sunshine days in September: 11.2 days

The month with the most sunshine days is January (21.8 days).
The month with the least sunshine days is September (11.2 days).

Average UV index in September
Helotes, TX

Average UV index in September - Helotes, TX
  • Average UV index in September: 6

The months with the highest UV index are June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).

Average cloud cover in September
Helotes, TX

Average cloud cover in September - Helotes, TX
  • Average cloud cover in September: 34

The months with the most cloud cover are March and May (Cloud cover 46).
The month with the least cloud cover is August (Cloud cover 23).

Average visibility in September
Helotes, TX

Average visibility in September - Helotes, 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).

Helotes, Texas, USA

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