September weather forecastWesterville, OH
September
Weather in September
September unfolds the arrival of autumn in Westerville. The change from summer to autumn is subtly reflected through a noticeable dip in temperature and a decrease in rainfall, now averaging 1.1" (28mm). Days begin to shorten and the wind strengthens from its summer lull. The humidity remains steady while the atmospheric pressure gradually climbs, indicating a transition towards a cooler season. By the end of the month, richer autumn hues begin to dominate the city’s panorama.Temperature
The onset of September in Westerville aligns with a soft reduction in the average high-temperature, gently falling from 81°F (27.2°C) in August to a still warm 75°F (23.9°C). In September, the recorded average low-temperature is a refreshing 56.8°F (13.8°C).Humidity
In September, the average relative humidity in Westerville is 76%.Rainfall
In Westerville, in September, during 12.2 rainfall days, 1.1" (28mm) of precipitation is typically accumulated. Throughout the year, in Westerville, there are 149 rainfall days, and 18.5" (470mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall in Westerville.Daylight
In September, the average length of the day in Westerville is 12h and 26min.On the first day of September, sunrise is at 7:00 am and sunset at 8:02 pm. On the last day of the month, sunrise is at 7:27 am and sunset at 7:15 pm EDT.
Sunshine
In Westerville, the average sunshine in September is 8.3h.UV index
The average daily maximum UV index in September in Westerville is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the average person.Note: The maximum daily UV index of 4 during September translates into the following directions:
Take precautions - Protection against skin and eye damage is obliged. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Enhance your sun protection with tightly woven, yet airy clothing.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Westerville, OH
- Average high temperature in September: 75°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (32.5°F).
- Average low temperature in September: 56.8°F
The month with the highest average low temperature is July (64.4°F).
The coldest month (with the lowest average low temperature) is January (20.7°F).
Average pressure in September
Westerville, OH
- 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 (29.94"Hg).
Average wind speed in September
Westerville, OH
- Average wind speed in September: 6.2mph
The windiest month (with the highest average wind speed) is January (9.7mph).
The calmest months (with the lowest average wind speed) are July and August (5.6mph).
Average humidity in September
Westerville, OH
- Average humidity in September: 76%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is October (74%).
Average rainfall in September
Westerville, OH
- Average rainfall in September: 1.1"
The wettest month (with the highest rainfall) is June (2.36").
The driest month (with the least rainfall) is February (0.98").
Average rainfall days in September
Westerville, OH
- Average rainfall days in September: 12.2 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is November (7.8 days).
Average snowfall in September
Westerville, OH
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.65").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Westerville, OH
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Westerville, OH
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in September: 8h and 18min
The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in September
Westerville, OH
- Average sunshine days in September: 15.2 days
The month with the most sunshine days is November (18.8 days).
The month with the least sunshine days is June (10.4 days).
Average UV index in September
Westerville, OH
- Average UV index in September: 4
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, February, November and December (UV index 2).
Average cloud cover in September
Westerville, OH
- Average cloud cover in September: 33
The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in September
Westerville, OH
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
