September weather forecast
Saint Marys, GA

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Weather in September

September marks the shift into autumn. The weather starts to cool down, and rainfall reduces significantly from August, lending a drier climate. Cloud coverage begins to increase, yet the daylight and sunshine hours endure, granting sufficient warmth. The temperature ranges from 73.8°F (23.2°C) to 85.8°F (29.9°C), shedding some of summer's intense heat.

Temperature

The average high-temperature is a warm 85.8°F (29.9°C) in September, hardly different from the 90°F (32.2°C) recorded in August. During September, Saint Marys sees a mean low-temperature of 73.8°F (23.2°C).

Heat index

In September, the heat index is evaluated at a sweltering 96.8°F (36°C). Undertake additional safety actions, risk of heat cramps and heat exhaustion is significant. Persistent activity may induce heatstroke.
Understand that the heat index values take into account shaded locations and mild winds. Heat index values may rise by up to 15 Fahrenheit (8 Celsius) degrees when exposed to direct sunlight.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. The impact of weather on an individual can be subjective, affected by the person's activity and heat perception, which can vary due to elements including wind, clothing, and metabolic differences. One should be aware that direct sunshine can amplify the perceived temperature, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Younglings frequently fail to recognize the requirement to rest and rehydrate. Thirst emerges late in dehydration - it is imperative to keep hydration levels high, particularly during extended physical exertions.
Sweat evaporation, driven by perspiration, is the method the human body uses to rid itself of excessive warmth. With an abundance of moisture present in the air, the process of evaporation becomes less effective, and the body fails to cool down as it should, leading to the sensation of overheating. When heat gain surpasses the level the body can shed, body temperature begins to increase, and consequently, overheating and dehydration can occur, with varying severity.

Humidity

In Saint Marys, the average relative humidity in September is 76%.

Rainfall

In Saint Marys, in September, during 18.5 rainfall days, 2.68" (68mm) of precipitation is typically accumulated. Throughout the year, in Saint Marys, there are 165.4 rainfall days, and 23.15" (588mm) of precipitation is accumulated.

Snowfall

In Saint Marys, snow does not fall in January, March through December.

Daylight

The average length of the day in September is 12h and 20min.
On the first day of the month, sunrise is at 7:03 am and sunset at 7:49 pm. On the last day of September, sunrise is at 7:19 am and sunset at 7:12 pm EDT.

Sunshine

In Saint Marys, the average sunshine in September is 8.6h.

UV index

In September, the average daily maximum UV index in Saint Marys is 6. A UV Index reading of 6 to 7 represents a high threat to health from exposure to the Sun's UV radiation for the ordinary person.
Note: The average daily UV index of 6 in September transforms into the following instructions:
Act on precautions and pay attention to sun safety recommendations. Avoidance of sunburn is obligatory. Between 10 a.m. and 4 p.m., the Sun emits the most powerful UV radiation. Limit direct exposure to the Sun during these hours. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation.

Frequently asked questions

How hot is September?

The high-temperature during September is 85.8°F (29.9°C) and the low-temperature is 73.8°F (23.2°C). In September, the average heat index (a.k.a. 'feels like', 'apparent temperature'), which factors the actual air temperature with the relative humidity, is evaluated at 96.8°F (36°C).

What is the average humidity in September?

The average relative humidity in September is 76%.

How much does it rain in Saint Marys in September?

In Saint Marys, Georgia, during September, the rain falls for 18.5 days and regularly aggregates up to 2.68" (68mm) of precipitation.

When it does not snow?

January, March through December are months without snowfall.

How many hours of daylight does Saint Marys have in September?

The average day length in September is 12h and 20min.

When are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 7:03 am and sunset at 7:49 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 7:12 pm EDT.

How long on average sun shines in September?

In Saint Marys, the average sunshine duration in September is 8.6h.

What is the UV index intensity in September in Saint Marys?

In Saint Marys, the average daily maximum UV index in September is 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Saint Marys, GA

Average temperature in September - Saint Marys, GA
  • Average high temperature in September: 85.8°F

The warmest month (with the highest average high temperature) is July (90.1°F).
The month with the lowest average high temperature is January (61.5°F).

  • Average low temperature in September: 73.8°F

The month with the highest average low temperature is August (76.8°F).
The coldest month (with the lowest average low temperature) is January (47.7°F).

Average pressure in September
Saint Marys, GA

Average pressure in September - Saint Marys, GA
  • Average pressure in September: 29.98"Hg

The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.98"Hg).

Average wind speed in September
Saint Marys, GA

Average wind speed in September - Saint Marys, GA
  • Average wind speed in September: 6.6mph

The windiest month (with the highest average wind speed) is April (7.6mph).
The calmest months (with the lowest average wind speed) are July and August (6mph).

Average humidity in September
Saint Marys, GA

Average humidity in September - Saint Marys, GA
  • Average humidity in September: 76%

The months with the highest relative humidity are August and December (77%).
The month with the lowest relative humidity is March (71%).

Average rainfall in September
Saint Marys, GA

Average rainfall in September - Saint Marys, GA
  • Average rainfall in September: 2.68"

The wettest month (with the highest rainfall) is August (3.9").
The driest month (with the least rainfall) is January (0.67").

Average rainfall days in September
Saint Marys, GA

Average rainfall days in September - Saint Marys, GA
  • Average rainfall days in September: 18.5 days

The month with the highest number of rainy days is August (23.9 days).
The month with the least rainy days is February (8.3 days).

Average snowfall days in September
Saint Marys, GA

Average snowfall days in September - Saint Marys, GA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (0.1 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October, November and December (0 days).

Average daylight in September /
Average sunshine in September
Saint Marys, GA

Average daylight in September / Average sunshine in September - Saint Marys, GA
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 14h and 6min).
The month with the shortest days is December (Average daylight: 10h and 12min).

  • Average sunshine in September: 8h and 4min

The month with the most sunshine is July (Average sunshine: 10h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).

Average sunshine days in September
Saint Marys, GA

Average sunshine days in September - Saint Marys, GA
  • Average sunshine days in September: 8.7 days

The month with the most sunshine days is January (20.8 days).
The month with the least sunshine days is August (4.5 days).

Average UV index in September
Saint Marys, GA

Average UV index in September - Saint Marys, GA
  • 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 4).

Average cloud cover in September
Saint Marys, GA

Average cloud cover in September - Saint Marys, GA
  • Average cloud cover in September: 31

The month with the most cloud cover is December (Cloud cover 39).
The month with the least cloud cover is May (Cloud cover 27).

Average visibility in September
Saint Marys, GA

Average visibility in September - Saint Marys, GA
  • 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).

Saint Marys, Georgia, USA

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