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
During September, Callahan records an average high-temperature of a still hot 86.9°F (30.5°C), marking a slight divergence from August's 90.9°F (32.7°C). In Callahan, September nights witness a steady temperature drop to a warm 73.4°F (23°C).Heat index
September's average heat index is calculated to be a very hot 100.4°F (38°C). Emphasize additional safety, risk of heat cramps and heat exhaustion is high. Continuous activity might result in heatstroke.Be advised, the heat index considers values for conditions in shade and with a light breeze. Exposure to the sun directly might heighten the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is an index that combines air temperature and relative humidity to determine the human-perceived temperature equivalent. The effect is experienced differently by individuals, hinging on unique characteristics such as body mass, stature, and level of activity. Direct exposure to the sun's rays can enhance the felt temperature, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Young children are generally more endangered than adults, as they usually less sweat. And also, due to larger skin surface relative to their small bodies and higher heat production as a result of their activity.
Perspiration is the human body's physiological response to high temperatures and is an attempt to lower body temperature through evaporation of sweat. An increase in relative humidity hinders the body's normal cooling function by reducing evaporation, thereby decreasing the rate of body cooling and enhancing the sense of warmth. Excessive heat gain, when not shed effectively by the body, can result in increasing body temperatures and related hazards.
Humidity
In Callahan, the average relative humidity in September is 76%.Rainfall
In Callahan, in September, during 16.8 rainfall days, 2.48" (63mm) of precipitation is typically accumulated. In Callahan, during the entire year, the rain falls for 165.4 days and collects up to 28.39" (721mm) of precipitation.Snowfall
March through December are months without snowfall.Daylight
The average length of the day in September is 12h and 20min.On the first day of September, sunrise is at 7:04 am and sunset at 7:49 pm. On the last day of the month, sunrise is at 7:20 am and sunset at 7:13 pm EDT.
Sunshine
In Callahan, the average sunshine in September is 8.5h.UV index
The average daily maximum UV index in September is 6. A UV Index reading of 6 to 7 represents a high health risk from unsafe exposure to UV radiation for ordinary individuals.Note: In September, the maximum UV index of 6 translates into these guidelines:
Prevent overexposure. Protection from the sun's harmful effects is needed. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Is it hot in Callahan 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 are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Callahan, FL
- Average high temperature in September: 86.9°F
The warmest month (with the highest average high temperature) is July (91.2°F).
The month with the lowest average high temperature is January (63°F).
- Average low temperature in September: 73.4°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 (46.8°F).
Average pressure in September
Callahan, FL
- 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
Callahan, FL
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is April (6.8mph).
The calmest months (with the lowest average wind speed) are July and August (5.3mph).
Average humidity in September
Callahan, FL
- Average humidity in September: 76%
The month with the highest relative humidity is December (77%).
The month with the lowest relative humidity is March (70%).
Average rainfall in September
Callahan, FL
- Average rainfall in September: 2.48"
The wettest month (with the highest rainfall) is August (4.09").
The driest month (with the least rainfall) is January (1.3").
Average rainfall days in September
Callahan, FL
- Average rainfall days in September: 16.8 days
The month with the highest number of rainy days is August (22.6 days).
The month with the least rainy days is November (8.7 days).
Average snowfall days in September
Callahan, FL
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (0.1 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Callahan, FL
- 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 3min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in September
Callahan, FL
- Average sunshine days in September: 11.4 days
The month with the most sunshine days is January (19.9 days).
The month with the least sunshine days is August (6.8 days).
Average UV index in September
Callahan, FL
- 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
Callahan, FL
- Average cloud cover in September: 33
The month with the most cloud cover is December (Cloud cover 41).
The month with the least cloud cover is May (Cloud cover 28).
Average visibility in September
Callahan, 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).
Callahan, Florida, USA
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