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
With September's arrival, Olney sees a decrease in average high-temperatures, moving from a warm 77.5°F (25.3°C) in August to a comfortable 65.3°F (18.5°C). Olney's average low-temperature for the month of September denotes a significant decline from the daily high, recording at a wintry 38.5°F (3.6°C).Humidity
The average relative humidity in September in Olney, Montana, is 64%.Rainfall
In September, the rain falls for 9 days. Throughout September, 0.87" (22mm) of precipitation is accumulated. Throughout the year, there are 136.9 rainfall days, and 16.46" (418mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall in Olney. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.04" (1mm) of snow. In Olney, during the entire year, snow falls for 107.6 days and aggregates up to 51.42" (1306mm) of snow.Daylight
In Olney, the average length of the day in September is 12h and 34min.On the first day of September, sunrise is at 6:56 am and sunset at 8:19 pm. On the last day of the month, sunrise is at 7:37 am and sunset at 7:18 pm MDT.
Sunshine
The average sunshine in September in Olney is 9.3h.UV index
In September, the average daily maximum UV index in Olney is 3. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for the average person.Note: The UV index of 3 during September translates into the following guidance:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Stay sun-safe with clothing that is both closely woven and worn loosely. Remember to consider! The UV radiation from the Sun can be intensified nearly twice by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Olney in September?
What is the average humidity in September in Olney?
How many days does it rain in September in Olney?
When does it start snowing in Olney?
What is the average length of the day in September in Olney?
What time are sunrise and sunset in September in Olney?
How long on average sun shines in September in Olney?
What is the UV index intensity in September in Olney?
Average temperature in September
Olney, MT
- Average high temperature in September: 65.3°F
The warmest month (with the highest average high temperature) is July (78.1°F).
The month with the lowest average high temperature is December (25.5°F).
- Average low temperature in September: 38.5°F
The month with the highest average low temperature is August (45°F).
The coldest month (with the lowest average low temperature) is February (12.7°F).
Average pressure in September
Olney, MT
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Olney, MT
- Average wind speed in September: 3.7mph
The windiest month (with the highest average wind speed) is April (4.5mph).
The calmest month (with the lowest average wind speed) is December (3.5mph).
Average humidity in September
Olney, MT
- Average humidity in September: 64%
The month with the highest relative humidity is January (94%).
The months with the lowest relative humidity are July and August (56%).
Average rainfall in September
Olney, MT
- Average rainfall in September: 0.87"
The wettest month (with the highest rainfall) is March (1.93").
The driest month (with the least rainfall) is August (0.51").
Average rainfall days in September
Olney, MT
- Average rainfall days in September: 9 days
The month with the highest number of rainy days is April (16.6 days).
The month with the least rainy days is August (6.4 days).
Average snowfall in September
Olney, MT
- Average snowfall in September: 0.04"
The month with the highest snowfall is January (11.02").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Olney, MT
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is December (21.4 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Olney, MT
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 9h and 2min
The months with the most sunshine are July and August (Average sunshine: 11h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 24min).
Average sunshine days in September
Olney, MT
- Average sunshine days in September: 18.7 days
The month with the most sunshine days is August (22.3 days).
The month with the least sunshine days is March (6.3 days).
Average UV index in September
Olney, MT
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in September
Olney, MT
- Average cloud cover in September: 25
The month with the most cloud cover is January (Cloud cover 66).
The month with the least cloud cover is August (Cloud cover 15).
Average visibility in September
Olney, MT
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The months with the lowest visibility are January and February (3mi).
Olney, Montana, USA
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