September weather forecastLester, IA
September
Weather in September
September, the first month of the autumn in Lester, is still a warm month, with an average temperature ranging between max 73.9°F (23.3°C) and min 53.6°F (12°C).Temperature
September's onset introduces a mild reduction in the average high-temperature, from 80.2°F (26.8°C) in August to a still moderately hot 73.9°F (23.3°C). In September, the temperature drops to an average of 53.6°F (12°C) at night.Humidity
In September, the average relative humidity is 71%.Rainfall
In Lester, in September, it is raining for 11.3 days, with typically 2.09" (53mm) of accumulated precipitation. In Lester, during the entire year, the rain falls for 119.2 days and collects up to 22.13" (562mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 29min.On the first day of September, sunrise is at 6:50 am and sunset at 8:00 pm. On the last day of the month, sunrise is at 7:22 am and sunset at 7:07 pm CDT.
Sunshine
In September, the average sunshine is 8.9h.UV index
The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the average person.Note: The maximum daily UV index of 4 during September translates into the following directions:
Take precautions. Light skin individuals may get burned in less than 30 minutes. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Lester, IA
- Average high temperature in September: 73.9°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (23°F).
- Average low temperature in September: 53.6°F
The month with the highest average low temperature is July (62.8°F).
The coldest month (with the lowest average low temperature) is January (9.5°F).
Average pressure in September
Lester, IA
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in September
Lester, IA
- Average wind speed in September: 9.3mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is July (7.8mph).
Average humidity in September
Lester, IA
- Average humidity in September: 71%
The month with the highest relative humidity is January (88%).
The month with the lowest relative humidity is October (67%).
Average rainfall in September
Lester, IA
- Average rainfall in September: 2.09"
The wettest month (with the highest rainfall) is June (3.43").
The driest month (with the least rainfall) is January (0.71").
Average rainfall days in September
Lester, IA
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is June (17.3 days).
The month with the least rainy days is February (2.7 days).
Average snowfall in September
Lester, IA
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.61").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Lester, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (11.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Lester, IA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 8h and 54min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in September
Lester, IA
- Average sunshine days in September: 17 days
The month with the most sunshine days is November (20.1 days).
The month with the least sunshine days is June (10.1 days).
Average UV index in September
Lester, IA
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Lester, IA
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 56).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in September
Lester, IA
- 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).





