September weather forecastKing William, VA
September
Weather in September
The first month of the autumn, September, is still a warm month in King William, Virginia, with an average temperature varying between 80.6°F (27°C) and 62.8°F (17.1°C).Temperature
King William's weather in September involves a mild decrease in the average high-temperature, moving down slightly from August's hot 87.4°F (30.8°C) to a moderately hot 80.6°F (27°C). King William experiences an average nighttime temperature of 62.8°F (17.1°C) in the month of September.Heat index
The heat index in September is appraised at 84.2°F (29°C). If one sustains activity during exposure, it could lead to a sense of fatigue, with a chance of heat cramps.Research indicates the heat index considers values in shaded locales and with light winds. Heat index values may be hiked up by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is found by incorporating humidity levels into the air temperature measurement. One's weather perception can be influenced by a range of factors including metabolic differences, being pregnant, and their level of physical activity. Should you be directly under the sun, anticipate a possible increase in the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Children typically face more danger than adults as their sweat production is usually lower. Additionally, the bigger skin surface compared to their small size and the increased heat due to their activeness exacerbate the risk.
Humidity
In September, the average relative humidity is 76%.Rainfall
September is the month with the least rainfall. Rain falls for 11.9 days and accumulates 1.77" (45mm) of precipitation.Snowfall
In King William, snow does not fall in May through October.Daylight
In King William, the average length of the day in September is 12h and 25min.On the first day of the month, sunrise is at 6:38 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
In King William, the average sunshine in September is 8.8h.UV index
In King William, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: The UV index of 5 in September translates into these instructions:
Undertake protective steps - Obligation to safeguard skin and eyes from harm is in place. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. To cut down UV radiation exposure by about half, sport a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
King William, VA
- Average high temperature in September: 80.6°F
The warmest month (with the highest average high temperature) is July (89.6°F).
The month with the lowest average high temperature is January (44.2°F).
- Average low temperature in September: 62.8°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 (29.3°F).
Average pressure in September
King William, 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
King William, VA
- Average wind speed in September: 5.6mph
The windiest month (with the highest average wind speed) is April (7.4mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
King William, VA
- Average humidity in September: 76%
The month with the highest relative humidity is December (79%).
The month with the lowest relative humidity is July (71%).
Average rainfall in September
King William, VA
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is August (2.99").
The driest month (with the least rainfall) is September (1.77").
Average rainfall days in September
King William, VA
- Average rainfall days in September: 11.9 days
The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is January (9.8 days).
Average snowfall in September
King William, VA
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.93").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
King William, VA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (3.9 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
King William, 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 36min).
The months with the least sunshine are February and December (Average sunshine: 5h and 18min).
Average sunshine days in September
King William, VA
- Average sunshine days in September: 16.7 days
The month with the most sunshine days is November (19.1 days).
The month with the least sunshine days is May (11.8 days).
Average UV index in September
King William, 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
King William, VA
- Average cloud cover in September: 38
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in September
King William, VA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October and November (6mi).
The months with the lowest visibility are May and December (5mi).
