September weather forecast
Ennis, MT

Share

Weather in September

September is a picturesque period in Ennis. The shift from the heat of August towards cooler autumn temperatures is a respite. There is a marginal decline in temperature and a slight increase in rainfall, signaling the onset of the fall season. The changing foliage and the falling leaves craft a beautiful autumnal landscape. The weather still allows for impressive outdoor excursions, making September an inviting period for a fall getaway.

Temperature

The beginning of September marks a decrease in the average high-temperature, transitioning from an agreeable 73°F (22.8°C) in August to an enjoyable 63.5°F (17.5°C). A noticeable temperature swing characterizes Ennis's September nights, dipping to an average of 39.9°F (4.4°C).

Humidity

The average relative humidity in September is 56%.

Rainfall

In Ennis, Montana, in September, during 10.3 rainfall days, 1.61" (41mm) of precipitation is typically accumulated. Throughout the year, in Ennis, there are 105.7 rainfall days, and 17.99" (457mm) of precipitation is accumulated.

Snowfall

Months with snowfall in Ennis are January through December. In Ennis, Montana, in September, during 3.9 snowfall days, 4.37" (111mm) of snow is typically accumulated. Throughout the year, there are 136.1 snowfall days, and 86.93" (2208mm) of snow is accumulated.

Daylight

In Ennis, the average length of the day in September is 12h and 31min.
On the first day of the month, sunrise is at 6:49 am and sunset at 8:03 pm. On the last day of September, sunrise is at 7:24 am and sunset at 7:08 pm MDT.

Sunshine

In September, the average sunshine is 9.7h.

UV index

The average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.
Note: The maximum UV index of 3 during September translates into these guidelines:
Undertake precautions - Obligation exists to protect against skin and eye damage. The Sun's radiation is especially intense around midday; try to stay in shade during this period. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Updated: Feb 13, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the average September temperature in Ennis?

The high-temperature, in September, in Ennis, is 63.5°F (17.5°C), while the low-temperature averages to 39.9°F (4.4°C).

What is the average humidity in September in Ennis?

In September, the average relative humidity is 56%.

How much does it rain in Ennis in September?

In Ennis, Montana, in September, during 10.3 rainfall days, 1.61" (41mm) of precipitation is typically accumulated.

How much does it snow in Ennis in September?

In Ennis, Montana, during September, snow falls for 3.9 days and regularly aggregates up to 4.37" (111mm) of snow.

What is the average length of the day in September in Ennis?

The average day length in September in Ennis, Montana, is 12h and 31min.

What time are sunrise and sunset in September in Ennis?

In September, on the first day of the month, sunrise is at 6:49 am and sunset at 8:03 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 7:08 pm MDT.

How many hours of sunshine does Ennis have in September?

In Ennis, the average sunshine duration in September is 9.7h.

How high is the UV index in September in Ennis?

The average daily maximum UV index in September in Ennis is 3. A UV Index value of 3 to 5 symbolizes a medium hazard to health from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Ennis, MT

Average temperature in September - Ennis, MT
  • Average high temperature in September: 63.5°F

The warmest month (with the highest average high temperature) is July (74.5°F).
The month with the lowest average high temperature is December (22.3°F).

  • Average low temperature in September: 39.9°F

The month with the highest average low temperature is August (46°F).
The coldest month (with the lowest average low temperature) is December (7.7°F).

Average pressure in September
Ennis, MT

Average pressure in September - Ennis, MT
  • Average pressure in September: 29.99"Hg

The month with the highest atmospheric pressure is January (30.22"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).

Average wind speed in September
Ennis, MT

Average wind speed in September - Ennis, MT
  • Average wind speed in September: 5.3mph

The windiest month (with the highest average wind speed) is January (7.1mph).
The calmest month (with the lowest average wind speed) is August (5mph).

Average humidity in September
Ennis, MT

Average humidity in September - Ennis, MT
  • Average humidity in September: 56%

The month with the highest relative humidity is February (90%).
The month with the lowest relative humidity is August (50%).

Average rainfall in September
Ennis, MT

Average rainfall in September - Ennis, MT
  • Average rainfall in September: 1.61"

The wettest month (with the highest rainfall) is May (2.36").
The driest month (with the least rainfall) is December (0.75").

Average rainfall days in September
Ennis, MT

Average rainfall days in September - Ennis, MT
  • Average rainfall days in September: 10.3 days

The month with the highest number of rainy days is June (16.5 days).
The month with the least rainy days is November (2.9 days).

Average snowfall in September
Ennis, MT

Average snowfall in September - Ennis, MT
  • Average snowfall in September: 4.37"

The month with the highest snowfall is April (14.76").
The month with the least snowfall is August (0.08").

Average snowfall days in September
Ennis, MT

Average snowfall days in September - Ennis, MT
  • Average snowfall days in September: 3.9 days

The month with the highest number of snowfall days is April (19.9 days).
The month with the least snowfall days is August (0.3 days).

Average daylight in September /
Average sunshine in September
Ennis, MT

Average daylight in September / Average sunshine in September - Ennis, MT
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).

  • Average sunshine in September: 9h and 4min

The month with the most sunshine is July (Average sunshine: 11h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).

Average sunshine days in September
Ennis, MT

Average sunshine days in September - Ennis, MT
  • Average sunshine days in September: 14.5 days

The month with the most sunshine days is January (16.3 days).
The month with the least sunshine days is April (6.9 days).

Average UV index in September
Ennis, MT

Average UV index in September - Ennis, MT
  • Average UV index in September: 3

The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January and February (UV index 1).

Average cloud cover in September
Ennis, MT

Average cloud cover in September - Ennis, MT
  • Average cloud cover in September: 23

The month with the most cloud cover is February (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 17).

Average visibility in September
Ennis, MT

Average visibility in September - Ennis, MT
  • Average visibility in September: 6mi

The months with the highest visibility are June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (4mi).

Ennis, Montana, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location