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
A change in temperatures is noted as August gives way to September, with average highs reducing from a moderately hot 84.4°F (29.1°C) to a still warm 73.6°F (23.1°C). A sharp contrast between day and night is prevalent in September with an average nighttime temperature of 49.5°F (9.7°C).Humidity
In Iona, Idaho, the average relative humidity in September is 41%.Rainfall
The wettest months in Iona are May and September, with an average 0.83" (21mm) of rainfall.Snowfall
Months with snowfall in Iona are January through May, September through December. September is the first month it typically snows in Iona. Throughout September, in the average 0.1 snowfall days, it receives 0.04" (1mm) of snow. Throughout the year, there are 54.4 snowfall days, and 16.89" (429mm) of snow is accumulated.Daylight
In September, the average length of the day is 12h and 29min.On the first day of the month, sunrise is at 6:52 am and sunset at 8:02 pm. On the last day of September, in Iona, Idaho, sunrise is at 7:25 am and sunset at 7:09 pm MDT.
Sunshine
In September, the average sunshine is 10h.UV index
In Iona, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Prioritize safety - Recommendations to avert sunburn are shared. Exposing oneself to the midday Sun can be harmful due to the strong UV radiation; limit your time outside. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Frequently asked questions
What are the temperatures in Iona in September?
What is the average humidity in September in Iona?
What is the wettest month in Iona?
How many days does it rain in September in Iona?
When does it start to snow in Iona?
What is the average length of the day in September in Iona?
What time are sunrise and sunset in September in Iona?
How many hours of sunshine does Iona have in September?
What is the UV index reading in September in Iona?
Average temperature in September
Iona, ID
- Average high temperature in September: 73.6°F
The warmest month (with the highest average high temperature) is July (86.2°F).
The month with the lowest average high temperature is December (27.9°F).
- Average low temperature in September: 49.5°F
The month with the highest average low temperature is August (54.3°F).
The coldest month (with the lowest average low temperature) is January (14.2°F).
Average pressure in September
Iona, ID
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.3"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Iona, ID
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is April (9mph).
The calmest month (with the lowest average wind speed) is January (5.8mph).
Average humidity in September
Iona, ID
- Average humidity in September: 41%
The month with the highest relative humidity is January (90%).
The month with the lowest relative humidity is August (35%).
Average rainfall in September
Iona, ID
- Average rainfall in September: 0.83"
The wettest months (with the highest rainfall) are May and September (0.83").
The driest month (with the least rainfall) is July (0.35").
Average rainfall days in September
Iona, ID
- Average rainfall days in September: 8.1 days
The month with the highest number of rainy days is May (10.7 days).
The month with the least rainy days is January (3.7 days).
Average snowfall in September
Iona, ID
- Average snowfall in September: 0.04"
The month with the highest snowfall is January (3.86").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Iona, ID
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is December (12.9 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Iona, ID
- 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: 10h and 0min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in September
Iona, ID
- Average sunshine days in September: 19.4 days
The month with the most sunshine days is October (22.1 days).
The month with the least sunshine days is February (16.2 days).
Average UV index in September
Iona, ID
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover in September
Iona, ID
- Average cloud cover in September: 16
The months with the most cloud cover are January and February (Cloud cover 51).
The months with the least cloud cover are July and August (Cloud cover 11).
Average visibility in September
Iona, ID
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and February (4mi).
Iona, Idaho, USA
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