September weather forecastRunnells, IA
September
Weather in September
September, the first month of the autumn in Runnells, is still a warm month, with an average temperature varying between 76.1°F (24.5°C) and 55.9°F (13.3°C).Temperature
Runnells's transition into September involves a gentle shift in temperature, receding from 81.5°F (27.5°C) in August to a still warm 76.1°F (24.5°C). During the month of September, the temperature falls to an average of 55.9°F (13.3°C).Humidity
In Runnells, the average relative humidity in September is 76%.Rainfall
In September, the rain falls for 11.5 days. Throughout September, 2.6" (66mm) of precipitation is accumulated. In Runnells, during the entire year, the rain falls for 124.7 days and collects up to 26.34" (669mm) of precipitation.Snowfall
In Runnells, snow does not fall in June through September.Daylight
The average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:40 am and sunset at 7:46 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 6:56 pm CDT.
Sunshine
In September, the average sunshine is 9.1h.UV index
In Runnells, Iowa, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, a regular UV index of 4 translates into these guidelines:
Heed the precautions - Suggestions to avoid sunburn are made. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Runnells, IA
- Average high temperature in September: 76.1°F
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (28.4°F).
- Average low temperature in September: 55.9°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is January (14.9°F).
Average pressure in September
Runnells, IA
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in September
Runnells, IA
- Average wind speed in September: 7.9mph
The windiest months (with the highest average wind speed) are March and April (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.9mph).
Average humidity in September
Runnells, IA
- Average humidity in September: 76%
The months with the highest relative humidity are January, February and June (82%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Runnells, IA
- Average rainfall in September: 2.6"
The wettest month (with the highest rainfall) is May (4.45").
The driest month (with the least rainfall) is January (0.91").
Average rainfall days in September
Runnells, IA
- Average rainfall days in September: 11.5 days
The month with the highest number of rainy days is June (16.8 days).
The month with the least rainy days is February (4 days).
Average snowfall in September
Runnells, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.37").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Runnells, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Runnells, IA
- 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 12min).
- Average sunshine in September: 9h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in September
Runnells, IA
- Average sunshine days in September: 17.1 days
The month with the most sunshine days is November (18.7 days).
The month with the least sunshine days is June (11.7 days).
Average UV index in September
Runnells, IA
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Runnells, IA
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are July, August and September (Cloud cover 31).
Average visibility in September
Runnells, IA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).
