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 ushers in a slight temperature change, with average high-temperatures reducing from August's warm 76.8°F (24.9°C) to an enjoyable 65.5°F (18.6°C). Happy Haven's average low-temperature of 39.2°F (4°C) in September reflects a significant disparity from the daytime highs.Humidity
In September, the average relative humidity is 64%.Rainfall
In September, in Happy Haven, the rain falls for 8.5 days. Throughout September, 0.71" (18mm) of precipitation is accumulated. Throughout the year, there are 126.4 rainfall days, and 11.22" (285mm) of precipitation is accumulated.Snowfall
Months with snowfall in Happy Haven are January through May, September through December. September is the first month it typically snows in Happy Haven. Throughout September, in the average 0.3 snowfall days, it receives 0.04" (1mm) of snow. Throughout the year, there are 97 snowfall days, and 33.86" (860mm) of snow is accumulated.Daylight
In September, the average length of the day in Happy Haven is 12h and 34min.On the first day of September, sunrise is at 6:55 am and sunset at 8:18 pm. On the last day of the month, sunrise is at 7:36 am and sunset at 7:17 pm MDT.
Sunshine
The average sunshine in September is 9.4h.UV index
The average daily maximum UV index in September in Happy Haven, Montana, is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the ordinary person.Note: A maximum daily UV index of 3 during September morphs into the following directions:
Heed the precautions - Suggestions to avoid sunburn are made. The Sun is most powerful around mid-day, so it's a good practice to reduce direct exposure. Boost your sun resistance with garments that are densely woven yet spacious. Be cautious! The UV radiation from the Sun can be magnified almost twofold by snow reflection.
Frequently asked questions
What is the average September temperature in Happy Haven?
What is the average humidity in September in Happy Haven?
How much does it rain in Happy Haven in September?
When does it start to snow in Happy Haven?
What is the average length of the day in September in Happy Haven?
What time are sunrise and sunset in September in Happy Haven?
How long on average sun shines in September in Happy Haven?
How high is the UV index in September in Happy Haven?
Average temperature in September
Happy Haven, MT
- Average high temperature in September: 65.5°F
The warmest month (with the highest average high temperature) is July (77.9°F).
The month with the lowest average high temperature is December (25.7°F).
- Average low temperature in September: 39.2°F
The month with the highest average low temperature is August (45.5°F).
The coldest month (with the lowest average low temperature) is February (13.5°F).
Average pressure in September
Happy Haven, 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
Happy Haven, MT
- Average wind speed in September: 3.8mph
The windiest month (with the highest average wind speed) is April (4.6mph).
The calmest months (with the lowest average wind speed) are August and December (3.7mph).
Average humidity in September
Happy Haven, MT
- Average humidity in September: 64%
The month with the highest relative humidity is January (93%).
The month with the lowest relative humidity is August (55%).
Average rainfall in September
Happy Haven, MT
- Average rainfall in September: 0.71"
The wettest month (with the highest rainfall) is June (1.42").
The driest month (with the least rainfall) is August (0.43").
Average rainfall days in September
Happy Haven, MT
- Average rainfall days in September: 8.5 days
The month with the highest number of rainy days is April (15.8 days).
The month with the least rainy days is August (6.3 days).
Average snowfall in September
Happy Haven, MT
- Average snowfall in September: 0.04"
The month with the highest snowfall is January (7.72").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Happy Haven, MT
- Average snowfall days in September: 0.3 days
The month with the highest number of snowfall days is December (19.1 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Happy Haven, MT
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 9h and 2min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in September
Happy Haven, MT
- Average sunshine days in September: 19 days
The month with the most sunshine days is July (21.5 days).
The month with the least sunshine days is March (7.7 days).
Average UV index in September
Happy Haven, 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
Happy Haven, MT
- Average cloud cover in September: 24
The month with the most cloud cover is January (Cloud cover 65).
The months with the least cloud cover are July and August (Cloud cover 15).
Average visibility in September
Happy Haven, MT
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The month with the lowest visibility is January (3mi).
Happy Haven, Montana, USA
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