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
Bethesda experiences a minor change to a moderately hot 81.3°F (27.4°C) in average high-temperature during September, closely reflecting August. In Bethesda, September nights witness a steady temperature drop to a refreshing 61.9°F (16.6°C).Heat index
Throughout September, the heat index is evaluated at a hot 86°F (30°C). Extended exposure and activity might lead to tiredness, potentially resulting in heat cramps.When assessing, remember that heat index measurements are for light winds and shaded spots. If directly exposed to the sun, the heat index could rise by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', combines both the air temperature and the humidity level to give a perceived human temperature. This effect is subjective, differing among individuals based on their physical activity and perception of heat, which can be influenced by factors like wind, clothing, and metabolic variances. Awareness is key; direct sunlight can enhance the weather's impact, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. Children often miss understanding the importance of rest and rehydration. Thirst usually appears late during dehydration - therefore, maintaining hydration, particularly during long physical activities, is essential.
Humidity
In September, the average relative humidity is 76%.Rainfall
In September, the rain falls for 11.3 days. Throughout September, 0.98" (25mm) of precipitation is accumulated. In Bethesda, during the entire year, the rain falls for 141.9 days and collects up to 17.32" (440mm) of precipitation.Snowfall
In Bethesda, snow does not fall in April through October.Daylight
In September, the average length of the day is 12h and 23min.On the first day of the month, sunrise is at 6:19 am and sunset at 7:14 pm. On the last day of September, sunrise is at 6:41 am and sunset at 6:31 pm CDT.
Sunshine
In September, the average sunshine is 8.6h.UV index
The average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for the ordinary person.Note: The average daily UV index of 5 in September transforms into the following instructions:
Guard yourself - Avoiding sunburn is suggested. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Always opt for UVA and UVB-resistant sunglasses on radiant days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
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?
How many hours of sunshine does Bethesda have in September?
What is the UV index reading in September in Bethesda?
Average temperature in September
Bethesda, TN
- Average high temperature in September: 81.3°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (45.3°F).
- Average low temperature in September: 61.9°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 (30.9°F).
Average pressure in September
Bethesda, TN
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.97"Hg).
Average wind speed in September
Bethesda, TN
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is February (8.4mph).
The calmest months (with the lowest average wind speed) are July and August (4.6mph).
Average humidity in September
Bethesda, TN
- Average humidity in September: 76%
The month with the highest relative humidity is December (80%).
The month with the lowest relative humidity is October (74%).
Average rainfall in September
Bethesda, TN
- Average rainfall in September: 0.98"
The wettest month (with the highest rainfall) is July (2.17").
The driest month (with the least rainfall) is November (0.94").
Average rainfall days in September
Bethesda, TN
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is July (17.9 days).
The month with the least rainy days is November (7.2 days).
Average snowfall in September
Bethesda, TN
- Average snowfall in September: 0"
The months with the highest snowfall are February and December (0.2").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Bethesda, TN
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.1 days).
The months with the least snowfall days are April, May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Bethesda, TN
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in September
Bethesda, TN
- Average sunshine days in September: 16.9 days
The month with the most sunshine days is November (21.3 days).
The month with the least sunshine days is July (11.3 days).
Average UV index in September
Bethesda, TN
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 2).
Average cloud cover in September
Bethesda, TN
- Average cloud cover in September: 31
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is June (Cloud cover 29).
Average visibility in September
Bethesda, TN
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).
Bethesda, Tennessee, USA
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