September weather forecastWestlawn, IN
September
Weather in September
September in Westlawn, Indiana, marks the transition from summer to autumn. The month stands out with a noticeable decrease in temperature and a decreasing humidity level of 79%. Although remnants of hot summer days still linger, the arrival of cooler nights signals the encroaching change of seasons. With less daylight available, it’s time to pack away the summer gear as the weather starts gravitating towards fall. The noticeable shift in weather patterns during September serves as a preparation for the colder conditions expected in October.Temperature
The onset of September is marked by a minor decrease in temperature, transitioning from a warm 79.3°F (26.3°C) in August to a still moderately hot 73.9°F (23.3°C). Westlawn's temperature lowers to a mean of 55.8°F (13.2°C) during the nights in September.Humidity
In Westlawn, Indiana, the average relative humidity in September is 79%.Rainfall
In Westlawn, in September, during 11.2 rainfall days, 1.1" (28mm) of precipitation is typically accumulated. In Westlawn, during the entire year, the rain falls for 128.5 days and collects up to 15" (381mm) of precipitation.Snowfall
In Westlawn, snow does not fall in May through September.Daylight
In September, the average length of the day is 12h and 28min.On the first day of the month, sunrise is at 7:08 am and sunset at 8:13 pm. On the last day of September, sunrise is at 7:37 am and sunset at 7:24 pm EDT.
Sunshine
In September, the average sunshine is 7.9h.UV index
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In September, a daily UV index of 4 turns into the following recommendations:
Be vigilant - Preventing sunburn is recommended. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Westlawn, IN
- Average high temperature in September: 73.9°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (30.9°F).
- Average low temperature in September: 55.8°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (19.4°F).
Average pressure in September
Westlawn, IN
- Average pressure in September: 30.04"Hg
The months with the highest atmospheric pressure are January and November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Westlawn, IN
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is January (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.1mph).
Average humidity in September
Westlawn, IN
- Average humidity in September: 79%
The months with the highest relative humidity are January, February and December (83%).
The month with the lowest relative humidity is October (74%).
Average rainfall in September
Westlawn, IN
- Average rainfall in September: 1.1"
The wettest month (with the highest rainfall) is May (1.89").
The driest month (with the least rainfall) is February (0.79").
Average rainfall days in September
Westlawn, IN
- Average rainfall days in September: 11.2 days
The month with the highest number of rainy days is May (15.5 days).
The month with the least rainy days is January (5.4 days).
Average snowfall in September
Westlawn, IN
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.05").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Westlawn, IN
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.5 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Westlawn, IN
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 7h and 54min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 18min).
Average sunshine days in September
Westlawn, IN
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is November (19.3 days).
The month with the least sunshine days is June (12.5 days).
Average UV index in September
Westlawn, IN
- Average UV index in September: 4
The month with the highest UV index is June (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Westlawn, IN
- Average cloud cover in September: 37
The month with the most cloud cover is January (Cloud cover 66).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in September
Westlawn, IN
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
