September weather forecastRichmond, VA

September
Weather in September
September is characterized by a significant decrease in temperatures, ranging from 63.1°F (17.3°C) to 81.3°F (27.4°C). With autumn underway, Richmond swaps its warm, summery wardrobe for the subtle cooling associated with fall. This month witnesses a relative decrease in rainfall, paving the way for more open-air activities. The wind, although light, shows a slight increase in speed from the previous month. Despite the decreasing daylight hours, an abundance of sunshine prevents the onset of colder weather.Temperature
Richmond in September undergoes a slight reduction in the average high-temperature, shifting from August's hot 88.3°F (31.3°C) to a moderately hot 81.3°F (27.4°C). Richmond reports a consistent average low-temperature of 63.1°F (17.3°C) throughout September nights.Heat index
The average heat index in September is estimated at a hot 86°F (30°C). Uninterrupted exposure and activity might result in fatigue, potentially causing heat cramps.Data suggests that the heat index is set for environments in shade and with a light wind. The presence of direct sunlight can raise the heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'apparent temperature', binds temperature metrics with humidity values to give a sense of the actual warmth. 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. It is noteworthy to mention that direct sunlight exposure can augment the felt temperature, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to children. Children often fail to recognize the requirement to rest and rehydrate. Thirst, being a late symptom of dehydration, underlines the importance of maintaining hydration, especially during ongoing physical activities.
Humidity
The average relative humidity in September in Richmond is 73%.Rainfall
September is the month with the least rainfall in Richmond. Rain falls for 11.2 days and accumulates 1.73" (44mm) of precipitation.Snowfall
In Richmond, snow does not fall in May through October.Daylight
In September, the average length of the day in Richmond, Virginia, is 12h and 25min.On the first day of September in Richmond, sunrise is at 6:40 am and sunset at 7:38 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 6:53 pm EDT.
Sunshine
In September, the average sunshine is 8.6h.UV index
In Richmond, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: A maximum UV index of 5 in September translates into the following recommendations:
Preventative actions are necessary - Recommendations to ward off sunburn are given. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Richmond, VA
- Average high temperature in September: 81.3°F
The warmest month (with the highest average high temperature) is July (90.9°F).
The month with the lowest average high temperature is January (44.6°F).
- Average low temperature in September: 63.1°F
The month with the highest average low temperature is July (70.2°F).
The coldest month (with the lowest average low temperature) is January (29.7°F).
Average pressure in September
Richmond, 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
Richmond, VA
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is April (7.5mph).
The calmest month (with the lowest average wind speed) is August (5.3mph).
Average humidity in September
Richmond, VA
- Average humidity in September: 73%
The month with the highest relative humidity is December (78%).
The month with the lowest relative humidity is July (68%).
Average rainfall in September
Richmond, VA
- Average rainfall in September: 1.73"
The wettest month (with the highest rainfall) is August (2.87").
The driest month (with the least rainfall) is September (1.73").
Average rainfall days in September
Richmond, VA
- Average rainfall days in September: 11.2 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is November (9.7 days).
Average snowfall in September
Richmond, VA
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.05").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Richmond, VA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (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
Richmond, 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 36min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is December (Average sunshine: 5h and 6min).
Average sunshine days in September
Richmond, VA
- Average sunshine days in September: 17.8 days
The month with the most sunshine days is October (19.5 days).
The month with the least sunshine days is May (12.1 days).
Average UV index in September
Richmond, VA
- Average UV index in September: 5
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in September
Richmond, VA
- Average cloud cover in September: 39
The month with the most cloud cover is March (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in September
Richmond, 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).





