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 brings a decrease in the average high-temperature, shifting from a warm 78.3°F (25.7°C) in August to an agreeable 68.5°F (20.3°C). Harlowton's average low-temperature in September is measured at a chilly 47.1°F (8.4°C).Humidity
In Harlowton, Montana, the average relative humidity in September is 50%.Rainfall
In Harlowton, in September, it is raining for 8.3 days, with typically 0.94" (24mm) of accumulated precipitation. Throughout the year, in Harlowton, there are 128.6 rainfall days, and 12.8" (325mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.6 snowfall days, it receives 1.06" (27mm) of snow. In Harlowton, during the entire year, snow falls for 72.8 days and aggregates up to 33.5" (851mm) of snow.Daylight
The average length of the day in September in Harlowton is 12h and 32min.On the first day of the month, sunrise is at 6:40 am and sunset at 7:57 pm. On the last day of September, in Harlowton, sunrise is at 7:17 am and sunset at 7:00 pm MDT.
Sunshine
In Harlowton, the average sunshine in September is 10.3h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: A daily maximum UV index of 4 in September translates into the following instructions:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. The Sun's harshest UV rays are around midday; it's wise to seek shade and limit time outdoors. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature in Harlowton?
What is the average humidity in September in Harlowton?
How many days does it rain in September in Harlowton?
When does it start snowing in Harlowton?
What is the average length of the day in September in Harlowton?
What time are sunrise and sunset in September in Harlowton?
How long on average sun shines in September in Harlowton?
What is the UV index intensity in September in Harlowton?
Average temperature in September
Harlowton, MT
- Average high temperature in September: 68.5°F
The warmest month (with the highest average high temperature) is July (80.1°F).
The month with the lowest average high temperature is December (29.3°F).
- Average low temperature in September: 47.1°F
The months with the highest average low temperature are July and August (54.3°F).
The coldest month (with the lowest average low temperature) is February (16.3°F).
Average pressure in September
Harlowton, MT
- Average pressure in September: 29.95"Hg
The months with the highest atmospheric pressure are January and December (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in September
Harlowton, MT
- Average wind speed in September: 7.7mph
The windiest month (with the highest average wind speed) is January (10.9mph).
The calmest months (with the lowest average wind speed) are July and August (6.8mph).
Average humidity in September
Harlowton, MT
- Average humidity in September: 50%
The month with the highest relative humidity is January (78%).
The month with the lowest relative humidity is August (45%).
Average rainfall in September
Harlowton, MT
- Average rainfall in September: 0.94"
The wettest month (with the highest rainfall) is May (2.4").
The driest month (with the least rainfall) is December (0.47").
Average rainfall days in September
Harlowton, MT
- Average rainfall days in September: 8.3 days
The month with the highest number of rainy days is May (18.7 days).
The months with the least rainy days are January and December (7.2 days).
Average snowfall in September
Harlowton, MT
- Average snowfall in September: 1.06"
The month with the highest snowfall is April (6.61").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Harlowton, MT
- Average snowfall days in September: 0.6 days
The month with the highest number of snowfall days is February (14.2 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Harlowton, MT
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in September: 10h and 2min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 6h and 24min).
Average sunshine days in September
Harlowton, MT
- Average sunshine days in September: 19.2 days
The month with the most sunshine days is September (19.2 days).
The month with the least sunshine days is April (9 days).
Average UV index in September
Harlowton, MT
- 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, November and December (UV index 2).
Average cloud cover in September
Harlowton, MT
- Average cloud cover in September: 20
The month with the most cloud cover is February (Cloud cover 38).
The month with the least cloud cover is August (Cloud cover 15).
Average visibility in September
Harlowton, MT
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Harlowton, Montana, USA
Weather forecast for your location
2. Allow the app to use your location