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
The transition into September is accompanied by a temperature decrease, with the average high-temperature shifting from a moderately hot 78.3°F (25.7°C) in August to a refreshing 67.8°F (19.9°C). The average low-temperature reading in September for Heron reflects a significant fall from the daytime highs, stabilizing at a cold 41.7°F (5.4°C).Humidity
In Heron, the average relative humidity in September is 63%.Rainfall
In Heron, Montana, in September, it is raining for 10.7 days, with typically 1.14" (29mm) of accumulated precipitation. In Heron, during the entire year, the rain falls for 161.9 days and collects up to 27.48" (698mm) of precipitation.Snowfall
Months with snowfall are January through May, September through December. September is the first month it typically snows in Heron. Throughout September, in the average 0.3 snowfall days, it receives 0.28" (7mm) of snow. In Heron, during the entire year, snow falls for 80.8 days and aggregates up to 60" (1524mm) of snow.Daylight
In September, the average length of the day in Heron is 12h and 33min.On the first day of September, sunrise is at 7:03 am and sunset at 8:24 pm. On the last day of the month, sunrise is at 7:42 am and sunset at 7:24 pm MDT.
Sunshine
In September, the average sunshine in Heron is 9.5h.UV index
The average daily maximum UV index in September in Heron, Montana, is 3. A UV Index reading of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: In September, an average UV index of 3 transforms into the following instructions:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. The Sun's harshest UV rays are around midday; it's wise to seek shade and limit time outdoors. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Guard yourself! Snow reflection can almost double the UV radiation from the Sun.
Frequently asked questions
What are September temperatures in Heron?
What is the average humidity in September in Heron?
How many days does it rain in September in Heron?
When does it start to snow in Heron?
How many hours of daylight does Heron have in September?
When is the sunrise / sunset in September in Heron?
How long on average sun shines in September in Heron?
What is the UV index intensity in September in Heron?
Average temperature in September
Heron, MT
- Average high temperature in September: 67.8°F
The warmest month (with the highest average high temperature) is August (78.3°F).
The month with the lowest average high temperature is December (29.3°F).
- Average low temperature in September: 41.7°F
The month with the highest average low temperature is August (49.1°F).
The coldest month (with the lowest average low temperature) is December (18.7°F).
Average pressure in September
Heron, MT
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The months with the lowest atmospheric pressure are June and August (29.92"Hg).
Average wind speed in September
Heron, MT
- Average wind speed in September: 3.9mph
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
Heron, MT
- Average humidity in September: 63%
The month with the highest relative humidity is January (94%).
The month with the lowest relative humidity is August (52%).
Average rainfall in September
Heron, MT
- Average rainfall in September: 1.14"
The wettest month (with the highest rainfall) is December (3.66").
The driest month (with the least rainfall) is August (0.55").
Average rainfall days in September
Heron, MT
- Average rainfall days in September: 10.7 days
The month with the highest number of rainy days is April (19.3 days).
The month with the least rainy days is August (6.9 days).
Average snowfall in September
Heron, MT
- Average snowfall in September: 0.28"
The month with the highest snowfall is January (15.87").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Heron, MT
- Average snowfall days in September: 0.3 days
The month with the highest number of snowfall days is December (19.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Heron, 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 3min
The month with the most sunshine is August (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 12min).
Average sunshine days in September
Heron, MT
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is July (20.9 days).
The month with the least sunshine days is March (7.1 days).
Average UV index in September
Heron, 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
Heron, MT
- Average cloud cover in September: 25
The month with the most cloud cover is January (Cloud cover 67).
The month with the least cloud cover is August (Cloud cover 14).
Average visibility in September
Heron, MT
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February and December (3mi).
Heron, Montana, USA
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