September weather forecast
Jay Em, WY

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Weather in September

September, the first month of the autumn in Jay Em, is also a moderately hot month, with an average temperature fluctuating between 75.4°F (24.1°C) and 55.2°F (12.9°C).

Temperature

The shift from August to September includes a small decrease in the average high-temperature, from a moderately hot 83.8°F (28.8°C) to a still warm 75.4°F (24.1°C). During September, Jay Em observes a consistent average nighttime temperature of 55.2°F (12.9°C).

Humidity

The months with the lowest humidity are August and September, with an average relative humidity of 44%.

Rainfall

In September, the rain falls for 7.2 days. Throughout September, 0.67" (17mm) of precipitation is accumulated. Throughout the year, there are 94.7 rainfall days, and 10.39" (264mm) of precipitation is accumulated.

Snowfall

January through May, September through December are months with snowfall. September is the first month it typically snows in Jay Em. Throughout September, in the average 0.3 snowfall days, it receives 0.08" (2mm) of snow. In Jay Em, Wyoming, during the entire year, snow falls for 43.6 days and aggregates up to 15.63" (397mm) of snow.

Daylight

In Jay Em, the average length of the day in September is 12h and 28min.
On the first day of the month, sunrise is at 6:23 am and sunset at 7:31 pm. On the last day of September, sunrise is at 6:54 am and sunset at 6:40 pm MDT.

Sunshine

In September, the average sunshine is 10.6h.

UV index

In Jay Em, Wyoming, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for average individuals.
Note: A typical high UV index of 4 in September suggests the following recommendations:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades. Bear in mind! The Sun's UV radiation can nearly double in intensity due to the reflective quality of snow.
Updated: Jul 18, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the usual temperature for Jay Em in September?

In September, the average high-temperature and low-temperature are 75.4°F (24.1°C) and 55.2°F (12.9°C) respectively. In August, the average heat index (a.k.a. 'feels like', 'apparent temperature'), which represents the influence of relative humidity on air temperature, is computed to be 84.2°F (29°C).

What is the least humid month?

The months with the lowest humidity are August and September, with an average relative humidity of 44%.

What is the average humidity in September?

In September, the average relative humidity is 44%.

How many days does it rain in September?

In Jay Em, in September, it is raining for 7.2 days, with typically 0.67" (17mm) of accumulated precipitation.

When does it start snowing?

September is the first month it typically snows. Throughout September, in the average 0.3 snowfall days, it receives 0.08" (2mm) of snow.

How many hours of daylight does Jay Em have in September?

The average day length in September is 12h and 28min.

When is the sunrise / sunset in September?

On the first day of September, sunrise is at 6:23 am and sunset at 7:31 pm. On the last day of the month, sunrise is at 6:54 am and sunset at 6:40 pm MDT.

How many hours of sunshine does Jay Em have in September?

The average sunshine duration in September is 10.6h.

How high is the UV index in September?

The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium hazard to health from 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
Jay Em, WY

Average temperature in September - Jay Em, WY
  • Average high temperature in September: 75.4°F

The warmest month (with the highest average high temperature) is July (85.8°F).
The month with the lowest average high temperature is December (32°F).

  • Average low temperature in September: 55.2°F

The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is December (18.9°F).

Average pressure in September
Jay Em, WY

Average pressure in September - Jay Em, WY
  • Average pressure in September: 29.94"Hg

The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.84"Hg).

Average wind speed in September
Jay Em, WY

Average wind speed in September - Jay Em, WY
  • Average wind speed in September: 10.6mph

The windiest month (with the highest average wind speed) is April (11.9mph).
The calmest month (with the lowest average wind speed) is August (9.3mph).

Average humidity in September
Jay Em, WY

Average humidity in September - Jay Em, WY
  • Average humidity in September: 44%

The month with the highest relative humidity is January (74%).
The months with the lowest relative humidity are August and September (44%).

Average rainfall in September
Jay Em, WY

Average rainfall in September - Jay Em, WY
  • Average rainfall in September: 0.67"

The wettest months (with the highest rainfall) are May and June (1.57").
The driest month (with the least rainfall) is January (0.28").

Average rainfall days in September
Jay Em, WY

Average rainfall days in September - Jay Em, WY
  • Average rainfall days in September: 7.2 days

The month with the highest number of rainy days is May (13.4 days).
The month with the least rainy days is December (2.7 days).

Average snowfall in September
Jay Em, WY

Average snowfall in September - Jay Em, WY
  • Average snowfall in September: 0.08"

The month with the highest snowfall is March (2.56").
The months with the least snowfall are June, July and August (0").

Average snowfall days in September
Jay Em, WY

Average snowfall days in September - Jay Em, WY
  • Average snowfall days in September: 0.3 days

The month with the highest number of snowfall days is February (8 days).
The months with the least snowfall days are June, July and August (0 days).

Average daylight in September /
Average sunshine in September
Jay Em, WY

Average daylight in September / Average sunshine in September - Jay Em, WY
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).

  • Average sunshine in September: 10h and 4min

The months with the most sunshine are July and August (Average sunshine: 11h and 48min).
The months with the least sunshine are February and December (Average sunshine: 6h and 12min).

Average sunshine days in September
Jay Em, WY

Average sunshine days in September - Jay Em, WY
  • Average sunshine days in September: 20 days

The month with the most sunshine days is December (22.9 days).
The month with the least sunshine days is June (12.3 days).

Average UV index in September
Jay Em, WY

Average UV index in September - Jay Em, WY
  • Average UV index in September: 4

The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).

Average cloud cover in September
Jay Em, WY

Average cloud cover in September - Jay Em, WY
  • Average cloud cover in September: 17

The month with the most cloud cover is February (Cloud cover 36).
The month with the least cloud cover is August (Cloud cover 16).

Average visibility in September
Jay Em, WY

Average visibility in September - Jay Em, WY
  • 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).

Jay Em, Wyoming, USA

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