Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
September marks a gentle change in average high-temperature, declining from August's moderately hot 80.2°F (26.8°C) to a still warm 73.9°F (23.3°C). During September, the average low-temperature in Rock Rapids is a fresh 53.6°F (12°C).Humidity
In Rock Rapids, the average relative humidity in September is 71%.Rainfall
In Rock Rapids, in September, during 11.3 rainfall days, 2.09" (53mm) of precipitation is typically accumulated. Throughout the year, there are 119.2 rainfall days, and 22.13" (562mm) of precipitation is accumulated.Snowfall
In Rock Rapids, snow does not fall in June through September.Daylight
The average length of the day in September is 12h and 29min.On the first day of September, sunrise is at 6:49 am and sunset at 7:59 pm. On the last day of the month, sunrise is at 7:21 am and sunset at 7:06 pm CDT.
Sunshine
In Rock Rapids, the average sunshine in September is 8.9h.UV index
In September, the average daily maximum UV index in Rock Rapids is 4. A UV Index reading of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for ordinary individuals.Note: The daily high UV index of 4 during September translates into the following recommendations:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures in Rock Rapids?
What is the average humidity in September in Rock Rapids?
How many days does it rain in September in Rock Rapids?
When it does not snow in Rock Rapids?
Does it snow in Rock Rapids in September?
How many hours of daylight does Rock Rapids have in September?
When are sunrise and sunset in September in Rock Rapids?
How long on average sun shines in September in Rock Rapids?
What is the UV index reading in September in Rock Rapids?
Average temperature in September
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, IA
- Average daylight in September: 12h and 3min
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 5min
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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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
Rock Rapids, 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).
Rock Rapids, Iowa, USA
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