September weather forecast
Roy, UT

Share

Weather in September

September in Roy delineates a noticeable reduction in the summer heat, with a significant cooling effect—as temperatures decrease to a modest 72.5°F (22.5°C)—from the preceding summer months. The beginning of fall characterizes this month, with days gradually becoming shorter. Although summer activities gradually wind down, residents and tourists still exploit the warm weather to its fullest extent. This transition denotes a shift from the summer holiday spirit to the more routine, hustling environment of autumn.

Temperature

Roy in September undergoes a mild reduction in the average high-temperature, shifting from August's warm 81.9°F (27.7°C) to an agreeable 72.5°F (22.5°C). During the month of September, an average temperature of 52.7°F (11.5°C) is noted during the nights in Roy.

Humidity

In September, the average relative humidity is 44%.

Rainfall

In September, the rain falls for 7.5 days. Throughout September, 0.98" (25mm) of precipitation is accumulated. Throughout the year, there are 91.6 rainfall days, and 11.06" (281mm) of precipitation is accumulated.

Snowfall

January through May, September through December are months with snowfall. September is the first month it typically snows in Roy. Throughout September, in the average 0.2 snowfall days, it receives 0.39" (10mm) of snow. Throughout the year, there are 37.8 snowfall days, and 24.76" (629mm) of snow is accumulated.

Daylight

In Roy, the average length of the day in September is 12h and 27min.
On the first day of the month, sunrise is at 6:55 am and sunset at 8:00 pm. On the last day of September, sunrise is at 7:24 am and sunset at 7:11 pm MDT.

Sunshine

In September, the average sunshine is 9.9h.

UV index

In Roy, Utah, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for the ordinary person.
Note: The maximum UV index, 5 during September, leads to the following recommendations:
Undertake protective steps - Preventing sun damage is advised. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Updated: Aug 29, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the temperature in September?

An average high-temperature, in September, in Roy, is 72.5°F (22.5°C) and the average low-temperature is 52.7°F (11.5°C).

What is the average humidity in September?

In September, the average relative humidity is 44%.

How much does it rain in September?

In Roy, during September, the rain falls for 7.5 days and regularly aggregates up to 0.98" (25mm) of precipitation.

When does it start snowing?

September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.39" (10mm) of snow.

What is the average length of the day in September?

In September, the average day length is 12h and 27min.

What time are sunrise and sunset in September?

On the first day of September, sunrise is at 6:55 am and sunset at 8:00 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 7:11 pm MDT.

How many hours of sunshine does Roy have in September?

The average sunshine duration in September is 9.9h.

What is the UV index intensity in September?

In September, the average daily maximum UV index is 5. 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
Roy, UT

Average temperature in September - Roy, UT
  • Average high temperature in September: 72.5°F

The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (33.4°F).

  • Average low temperature in September: 52.7°F

The month with the highest average low temperature is July (60.4°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).

Average pressure in September
Roy, UT

Average pressure in September - Roy, UT
  • Average pressure in September: 29.95"Hg

The month with the highest atmospheric pressure is January (30.29"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).

Average wind speed in September
Roy, UT

Average wind speed in September - Roy, UT
  • Average wind speed in September: 5.8mph

The windiest month (with the highest average wind speed) is April (6.5mph).
The calmest month (with the lowest average wind speed) is January (4.8mph).

Average humidity in September
Roy, UT

Average humidity in September - Roy, UT
  • Average humidity in September: 44%

The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is July (37%).

Average rainfall in September
Roy, UT

Average rainfall in September - Roy, UT
  • Average rainfall in September: 0.98"

The wettest month (with the highest rainfall) is April (1.26").
The driest month (with the least rainfall) is July (0.43").

Average rainfall days in September
Roy, UT

Average rainfall days in September - Roy, UT
  • Average rainfall days in September: 7.5 days

The month with the highest number of rainy days is May (12.5 days).
The month with the least rainy days is January (4.6 days).

Average snowfall in September
Roy, UT

Average snowfall in September - Roy, UT
  • Average snowfall in September: 0.39"

The month with the highest snowfall is January (6.89").
The months with the least snowfall are June, July and August (0").

Average snowfall days in September
Roy, UT

Average snowfall days in September - Roy, UT
  • Average snowfall days in September: 0.2 days

The month with the highest number of snowfall days is January (8.8 days).
The months with the least snowfall days are June, July and August (0 days).

Average daylight in September /
Average sunshine in September
Roy, UT

Average daylight in September / Average sunshine in September - Roy, UT
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).

  • Average sunshine in September: 9h and 5min

The months with the most sunshine are June, July and August (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 5h and 36min).

Average sunshine days in September
Roy, UT

Average sunshine days in September - Roy, UT
  • Average sunshine days in September: 18.8 days

The months with the most sunshine days are October and November (21.6 days).
The month with the least sunshine days is April (14.7 days).

Average UV index in September
Roy, UT

Average UV index in September - Roy, UT
  • Average UV index in September: 5

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
Roy, UT

Average cloud cover in September - Roy, UT
  • Average cloud cover in September: 13

The months with the most cloud cover are January and February (Cloud cover 40).
The month with the least cloud cover is August (Cloud cover 10).

Average visibility in September
Roy, UT

Average visibility in September - Roy, UT
  • Average visibility in September: 6mi

The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).

Roy, Utah, USA

Weather forecast for your location

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