September weather forecastWashington, UT
September
Weather in September
September in Washington manifests a shift from summer to fall and is marked by gradually declining temperatures. The city witnesses shorter daylight hours as the sun sets earlier, and the nights grow longer. Winds shift subtly as the fall season progresses, facilitating relief from prior unbearable temperatures. Upon observation, this month registers a relief from summer's peak UV levels. Uninterrupted clear skies make for vibrant, crimson sunsets, a great visual treat for outdoorsy people.Temperature
With the onset of September, Washington experiences a modest temperature adjustment, with the average high-temperature gently receding from a tropical 92.3°F (33.5°C) in August to a moderately hot 85.1°F (29.5°C). The low-temperature averages to a refreshing 64.6°F (18.1°C) during the nights of September.Humidity
In September, the average relative humidity in Washington is 29%.Rainfall
In Washington, Utah, in September, during 4.9 rainfall days, 0.35" (9mm) of precipitation is typically accumulated. Throughout the year, there are 66.6 rainfall days, and 6.97" (177mm) of precipitation is accumulated.Snowfall
In Washington, Utah, snow does not fall in March through October.Daylight
In Washington, the average length of the day in September is 12h and 24min.On the first day of September in Washington, Utah, sunrise is at 7:05 am and sunset at 8:02 pm. On the last day of the month, sunrise is at 7:29 am and sunset at 7:18 pm MDT.
Sunshine
In Washington, Utah, the average sunshine in September is 9.9h.UV index
In Washington, the average daily maximum UV index in September is 6. A UV Index reading of 6 to 7 represents a high threat to health from exposure to the Sun's UV radiation for the average person.Note: The maximum daily UV index of 6 during September translates into the following directions:
Undertake precautions and comply with sun safety standards. Protection from skin and eye injury is vital. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Washington, UT
- Average high temperature in September: 85.1°F
The warmest month (with the highest average high temperature) is July (93.9°F).
The month with the lowest average high temperature is December (47.7°F).
- Average low temperature in September: 64.6°F
The month with the highest average low temperature is July (72.3°F).
The coldest month (with the lowest average low temperature) is December (31.6°F).
Average pressure in September
Washington, UT
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in September
Washington, UT
- Average wind speed in September: 5.6mph
The windiest month (with the highest average wind speed) is April (7.3mph).
The calmest months (with the lowest average wind speed) are August and December (5.3mph).
Average humidity in September
Washington, UT
- Average humidity in September: 29%
The month with the highest relative humidity is January (59%).
The month with the lowest relative humidity is June (18%).
Average rainfall in September
Washington, UT
- Average rainfall in September: 0.35"
The wettest month (with the highest rainfall) is March (0.98").
The driest month (with the least rainfall) is June (0.12").
Average rainfall days in September
Washington, UT
- Average rainfall days in September: 4.9 days
The month with the highest number of rainy days is March (8.3 days).
The month with the least rainy days is June (1.8 days).
Average snowfall in September
Washington, UT
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.2").
The months with the least snowfall are March, April, May, June, July, August, September and October (0").
Average snowfall days in September
Washington, UT
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (0.8 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Washington, UT
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in September: 9h and 54min
The months with the most sunshine are June and July (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 7h and 0min).
Average sunshine days in September
Washington, UT
- Average sunshine days in September: 21.5 days
The month with the most sunshine days is June (26.3 days).
The month with the least sunshine days is July (17.9 days).
Average UV index in September
Washington, UT
- Average UV index in September: 6
The months with the highest UV index are June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 2).
Average cloud cover in September
Washington, UT
- Average cloud cover in September: 8
The month with the most cloud cover is December (Cloud cover 21).
The month with the least cloud cover is June (Cloud cover 6).
Average visibility in September
Washington, UT
- 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).
