September weather forecast
Adna, WA

Share

Weather in September

September, the first month of the autumn in Adna, is still a pleasant month, with an average temperature varying between 70.3°F (21.3°C) and 46.9°F (8.3°C).

Temperature

With September's onset, the weather reveals a slight temperature decrease, transitioning from a warm 77.5°F (25.3°C) in August to an agreeable 70.3°F (21.3°C). A dramatic downturn marks the September nights, with lows averaging at a frosty 46.9°F (8.3°C).

Humidity

In September, the average relative humidity is 79%.

Rainfall

In Adna, in September, it is raining for 11.3 days, with typically 1.65" (42mm) of accumulated precipitation. In Adna, during the entire year, the rain falls for 185.5 days and collects up to 36.1" (917mm) of precipitation.

Snowfall

In Adna, snow does not fall in April through October.

Daylight

In Adna, the average length of the day in September is 12h and 32min.
On the first day of September, sunrise is at 6:33 am and sunset at 7:50 pm. On the last day of the month, sunrise is at 7:10 am and sunset at 6:53 pm PDT.

Sunshine

In Adna, the average sunshine in September is 8.3h.

UV index

In September, the average daily maximum UV index is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the average person.
Note: The UV index of 3 during September leads to these advisories:
Prioritize safety - Suggestions to prevent sun damage are offered. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Updated: Aug 18, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are September temperatures?

September temperatures vary between a high-temperature of 70.3°F (21.3°C) and a low-temperature of 46.9°F (8.3°C).

What is the average humidity in September?

The average relative humidity in September is 79%.

How much does it rain in September?

In Adna, in September, it is raining for 11.3 days, with typically 1.65" (42mm) of accumulated precipitation.

When it does not snow?

In Adna, snow does not fall in April through October.

What is the average length of the day in September?

The average day length in September is 12h and 32min.

When are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 6:33 am and sunset at 7:50 pm. On the last day of the month, sunrise is at 7:10 am and sunset at 6:53 pm PDT.

How many hours of sunshine does Adna have in September?

The average sunshine duration in September is 8.3h.

How high is the UV index in September?

In Adna, the average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate health threat from 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
Adna, WA

Average temperature in September - Adna, WA
  • Average high temperature in September: 70.3°F

The warmest month (with the highest average high temperature) is August (77.5°F).
The month with the lowest average high temperature is December (42.6°F).

  • Average low temperature in September: 46.9°F

The month with the highest average low temperature is August (50°F).
The coldest month (with the lowest average low temperature) is December (33.1°F).

Average pressure in September
Adna, WA

Average pressure in September - Adna, WA
  • Average pressure in September: 30.02"Hg

The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.02"Hg).

Average wind speed in September
Adna, WA

Average wind speed in September - Adna, WA
  • Average wind speed in September: 3.6mph

The windiest months (with the highest average wind speed) are January, March and November (4.5mph).
The calmest month (with the lowest average wind speed) is September (3.6mph).

Average humidity in September
Adna, WA

Average humidity in September - Adna, WA
  • Average humidity in September: 79%

The months with the highest relative humidity are January, February, November and December (89%).
The month with the lowest relative humidity is July (73%).

Average rainfall in September
Adna, WA

Average rainfall in September - Adna, WA
  • Average rainfall in September: 1.65"

The wettest month (with the highest rainfall) is January (5.51").
The driest month (with the least rainfall) is July (0.47").

Average rainfall days in September
Adna, WA

Average rainfall days in September - Adna, WA
  • Average rainfall days in September: 11.3 days

The month with the highest number of rainy days is March (21.5 days).
The month with the least rainy days is August (6.4 days).

Average snowfall in September
Adna, WA

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

The month with the highest snowfall is February (1.93").
The months with the least snowfall are April, May, June, July, August, September and October (0").

Average snowfall days in September
Adna, WA

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

The month with the highest number of snowfall days is February (3.5 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

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

Average daylight in September / Average sunshine in September - Adna, WA
  • Average daylight in September: 12h and 3min

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

  • Average sunshine in September: 8h and 2min

The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is December (Average sunshine: 3h and 30min).

Average sunshine days in September
Adna, WA

Average sunshine days in September - Adna, WA
  • Average sunshine days in September: 16.9 days

The months with the most sunshine days are July and August (20.8 days).
The month with the least sunshine days is February (7.6 days).

Average UV index in September
Adna, WA

Average UV index in September - Adna, WA
  • 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, February, November and December (UV index 2).

Average cloud cover in September
Adna, WA

Average cloud cover in September - Adna, WA
  • Average cloud cover in September: 47

The months with the most cloud cover are January, February and December (Cloud cover 65).
The month with the least cloud cover is August (Cloud cover 38).

Average visibility in September
Adna, WA

Average visibility in September - Adna, WA
  • Average visibility in September: 4mi

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

Adna, Washington, USA

Weather forecast for your location

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