September weather forecast
Monroe, WA

Share
The red Washington Water Powerhouse, next to a large bridge over the Spokane River and scenic waterfalls in Monroe, Washington
The red Washington Water Powerhouse, next to a large bridge over the Spokane River and scenic waterfalls in Monroe, Washington

Weather in September

September, the first month of the autumn in Monroe, is still a pleasant month, with an average temperature fluctuating between 68.7°F (20.4°C) and 47.3°F (8.5°C).

Temperature

Monroe's progression into September involves a minor drop in the average high-temperature, slightly receding from a moderately hot 75.6°F (24.2°C) in August to an agreeable 68.7°F (20.4°C). An average low-temperature of 47.3°F (8.5°C) is observed during the September nights.

Humidity

In Monroe, the average relative humidity in September is 76%.

Rainfall

In Monroe, Washington, in September, it is raining for 7.4 days, with typically 0.71" (18mm) of accumulated precipitation. Throughout the year, there are 115.8 rainfall days, and 11.81" (300mm) of precipitation is accumulated.

Snowfall

In Monroe, snow does not fall in May through October.

Daylight

The average length of the day in September in Monroe is 12h and 33min.
On the first day of September in Monroe, sunrise is at 6:27 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:06 am and sunset at 6:48 pm PDT.

Sunshine

In Monroe, the average sunshine in September is 9h.

UV index

In September, the average daily maximum UV index in Monroe is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for average individuals.
Note: The maximum daily UV index, 4 in September, converts into the following recommendations:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. To guard against the harmful effects of the Sun, minimize exposure during midday. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit.
[Resources]

Frequently asked questions

What is the temperature in September in Monroe?

The average high-temperature, in September, in Monroe, is 68.7°F (20.4°C), while the average low-temperature is 47.3°F (8.5°C).

What is the average humidity in September in Monroe?

The average relative humidity in September in Monroe is 76%.

How much does it rain in Monroe in September?

In Monroe, in September, it is raining for 7.4 days, with typically 0.71" (18mm) of accumulated precipitation.

When it does not snow in Monroe?

May through October are months without snowfall in Monroe.

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

In September, the average day length is 12h and 33min.

When are sunrise and sunset in September in Monroe?

In September, on the first day of the month, sunrise is at 6:27 am and sunset at 7:47 pm. On the last day of the month, in Monroe, Washington, sunrise is at 7:06 am and sunset at 6:48 pm PDT.

How many hours of sunshine does Monroe have in September?

The average sunshine duration in September in Monroe is 9h.

What is the UV index reading in September in Monroe?

The average daily maximum UV index in September in Monroe is 4. A UV Index value of 3 to 5 symbolizes a moderate vulnerability from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Monroe, WA

Average temperature in September - Monroe, WA
  • Average high temperature in September: 68.7°F

The warmest month (with the highest average high temperature) is August (75.6°F).
The month with the lowest average high temperature is December (41.2°F).

  • Average low temperature in September: 47.3°F

The month with the highest average low temperature is August (49.8°F).
The coldest month (with the lowest average low temperature) is December (31.8°F).

[Resources]

Average pressure in September
Monroe, WA

Average pressure in September - Monroe, WA
  • Average pressure in September: 30.01"Hg

The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).

[Resources]

Average wind speed in September
Monroe, WA

Average wind speed in September - Monroe, WA
  • Average wind speed in September: 3.5mph

The windiest month (with the highest average wind speed) is January (4.9mph).
The calmest month (with the lowest average wind speed) is August (3.3mph).

[Resources]

Average humidity in September
Monroe, WA

Average humidity in September - Monroe, WA
  • Average humidity in September: 76%

The months with the highest relative humidity are January, February and December (86%).
The month with the lowest relative humidity is July (71%).

[Resources]

Average rainfall in September
Monroe, WA

Average rainfall in September - Monroe, WA
  • Average rainfall in September: 0.71"

The wettest month (with the highest rainfall) is December (1.85").
The driest month (with the least rainfall) is August (0.2").

[Resources]

Average rainfall days in September
Monroe, WA

Average rainfall days in September - Monroe, WA
  • Average rainfall days in September: 7.4 days

The month with the highest number of rainy days is March (13.6 days).
The month with the least rainy days is August (4 days).

[Resources]

Average snowfall in September
Monroe, WA

Average snowfall in September - Monroe, WA
  • Average snowfall in September: 0"

The month with the highest snowfall is February (1.02").
The months with the least snowfall are May, June, July, August, September and October (0").

[Resources]

Average snowfall days in September
Monroe, WA

Average snowfall days in September - Monroe, WA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (2.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

[Resources]

Average daylight in September /
Average sunshine in September
Monroe, WA

Average daylight in September / Average sunshine in September - Monroe, WA
  • Average daylight in September: 12h and 4min

The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).

  • Average sunshine in September: 9h and 0min

The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 3h and 48min).

[Resources]

Average sunshine days in September
Monroe, WA

Average sunshine days in September - Monroe, WA
  • Average sunshine days in September: 21.1 days

The month with the most sunshine days is August (25.5 days).
The month with the least sunshine days is April (15 days).

[Resources]

Average UV index in September
Monroe, WA

Average UV index in September - Monroe, WA
  • Average UV index in September: 4

The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).

[Resources]

Average cloud cover in September
Monroe, WA

Average cloud cover in September - Monroe, WA
  • Average cloud cover in September: 38

The month with the most cloud cover is December (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 28).

[Resources]

Average visibility in September
Monroe, WA

Average visibility in September - Monroe, WA
  • Average visibility in September: 5mi

The month with the highest visibility is July (6mi).
The months with the lowest visibility are January, February, March, April, November and December (4mi).

[Resources]

Monroe, Washington, USA

Weather forecast for your location

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