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 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
September registers an average high-temperature of a warm 82.9°F (28.3°C), slightly varied from August's 87.6°F (30.9°C). The average temperature during September nights dips to a comfortable 62.6°F (17°C).Heat index
For September, the heat index is estimated at a hot 89.6°F (32°C). With sustained exposure and activity, exhaustion becomes probable, resulting in heat cramps.Evaluating the heat index requires understanding its values in the shade and with gentle winds. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is a metric representing the sensation of warmth when air temperature and moisture come together. The effect is experienced differently by individuals, hinging on unique characteristics such as body mass, stature, and level of activity. Being under direct sunshine can magnify the heat experience, possibly pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Kids are generally in more danger than adults because they perspire less. Their large skin surface area compared to their small bodies and the excessive heat due to their actions raises their risk.
Humidity
In September, the average relative humidity in Key, Alabama, is 75%.Rainfall
In September, the rain falls for 14.2 days. Throughout September, 2.72" (69mm) of precipitation is accumulated. In Key, during the entire year, the rain falls for 181.2 days and collects up to 41.06" (1043mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 22min.On the first day of the month, sunrise is at 6:16 am and sunset at 7:07 pm. On the last day of September, sunrise is at 6:36 am and sunset at 6:27 pm CDT.
Sunshine
The average sunshine in September is 8.5h.UV index
In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for the average person.Note: In September, the maximum UV index of 5 transforms into these recommendations:
Act with care - The need to guard against sun damage is communicated. The Sun is at its harshest during midday; protect yourself by staying in shaded areas and minimizing exposure. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What is the average humidity in September?
How many days 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 in Key?
How many hours of sunshine does Key have in September?
How high is the UV index in September?
Average temperature in September
Key, AL
- Average high temperature in September: 82.9°F
The warmest month (with the highest average high temperature) is July (88.7°F).
The month with the lowest average high temperature is January (48.9°F).
- Average low temperature in September: 62.6°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (33.4°F).
Average pressure in September
Key, AL
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in September
Key, AL
- Average wind speed in September: 4.5mph
The windiest month (with the highest average wind speed) is February (7.3mph).
The calmest month (with the lowest average wind speed) is August (4.1mph).
Average humidity in September
Key, AL
- Average humidity in September: 75%
The month with the highest relative humidity is December (80%).
The month with the lowest relative humidity is October (74%).
Average rainfall in September
Key, AL
- Average rainfall in September: 2.72"
The wettest months (with the highest rainfall) are February and December (4.06").
The driest month (with the least rainfall) is October (2.56").
Average rainfall days in September
Key, AL
- Average rainfall days in September: 14.2 days
The month with the highest number of rainy days is July (21.1 days).
The month with the least rainy days is November (9.8 days).
Average snowfall in September
Key, AL
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.79").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Key, AL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (1.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Key, AL
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 8h and 3min
The months with the most sunshine are June and July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Key, AL
- Average sunshine days in September: 13.4 days
The month with the most sunshine days is October (19.1 days).
The month with the least sunshine days is July (8 days).
Average UV index in September
Key, AL
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in September
Key, AL
- Average cloud cover in September: 31
The month with the most cloud cover is February (Cloud cover 48).
The month with the least cloud cover is June (Cloud cover 30).
Average visibility in September
Key, AL
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (5mi).
Key, Alabama, USA
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