September weather forecastMountcastle, VA
September
Weather in September
The first month of the autumn, September, is still a warm month in Mountcastle, Virginia, with an average temperature fluctuating between 80.8°F (27.1°C) and 63°F (17.2°C).Temperature
The average high-temperature slightly decreases in September, shifting from a tropical 87.1°F (30.6°C) in August to a warm 80.8°F (27.1°C). During September, Mountcastle experiences a consistent low-temperature average of 63°F (17.2°C).Heat index
During September, the heat index is computed to be a tropical 86°F (30°C). If one stays active during extended exposure, it might induce fatigue and result in heat cramps.It is crucial to understand that heat index figures are for shade and gentle wind conditions. The heat index can potentially augment by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', embodies the combination of air temperature and moisture content to illustrate perceived heat. The influence of weather is personal, with a diverse population experiencing it differently due to differences in body mass, stature, and degree of activity. Given the impact of direct sunlight, it's noteworthy that the felt temperature can rise by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Young individuals usually face more risks than adults due to their lower sweat production. Their large skin surface area relative to their tiny bodies and high heat production from their activities adds to their risk.
Humidity
The average relative humidity in September is 77%.Rainfall
The month with the least rainfall is September, when the rain falls for 13 days and typically collects 2.01" (51mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 25min.On the first day of the month, sunrise is at 6:39 am and sunset at 7:36 pm. On the last day of September, sunrise is at 7:03 am and sunset at 6:52 pm EDT.
Sunshine
The average sunshine in September is 8.8h.UV index
In Mountcastle, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum high UV index of 5 in September translates into the following recommendations:
Guard yourself - An obligation to protect skin and eyes from harm exists. Minimize direct exposure to the Sun during midday when its radiation is at its peak. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Mountcastle, VA
- Average high temperature in September: 80.8°F
The warmest month (with the highest average high temperature) is July (89.2°F).
The month with the lowest average high temperature is January (45.1°F).
- Average low temperature in September: 63°F
The month with the highest average low temperature is July (69.4°F).
The coldest month (with the lowest average low temperature) is January (30.2°F).
Average pressure in September
Mountcastle, VA
- Average pressure in September: 30.04"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in September
Mountcastle, VA
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is April (7.6mph).
The calmest month (with the lowest average wind speed) is August (5.3mph).
Average humidity in September
Mountcastle, VA
- Average humidity in September: 77%
The month with the highest relative humidity is December (79%).
The month with the lowest relative humidity is July (73%).
Average rainfall in September
Mountcastle, VA
- Average rainfall in September: 2.01"
The wettest month (with the highest rainfall) is August (3.7").
The driest month (with the least rainfall) is September (2.01").
Average rainfall days in September
Mountcastle, VA
- Average rainfall days in September: 13 days
The month with the highest number of rainy days is May (18.4 days).
The months with the least rainy days are January and November (10.2 days).
Average snowfall in September
Mountcastle, VA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.57").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Mountcastle, VA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.3 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
Mountcastle, VA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 5h and 12min).
Average sunshine days in September
Mountcastle, VA
- Average sunshine days in September: 14.9 days
The month with the most sunshine days is November (18.6 days).
The month with the least sunshine days is May (10.9 days).
Average UV index in September
Mountcastle, VA
- 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
Mountcastle, VA
- Average cloud cover in September: 39
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in September
Mountcastle, VA
- 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).
