September weather forecast
Cave Junction, OR

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Weather in September

The arrival of September signals the beginning of a transition from hot summer days towards milder autumn weather in Cave Junction. Although the average temperature still holds a high scale, standing at 77.4°F (25.2°C), it exhibits the start of a gradual cooling phase. Noticeably, September marks the end of no snowfall period lasting from May to September. The length of daylight begins to shorten, averaging at 12.5 hours, as nights gradually creep in earlier. Thus, September is a blend of lingering summer warmth and the onset of fall.

Temperature

September is characterized by a mild reduction in the average high-temperature, from 84.7°F (29.3°C) in August to a still warm 77.4°F (25.2°C). Cave Junction experiences a significant reduction from daytime highs with an average low-temperature of 45°F (7.2°C) in September.

Humidity

The average relative humidity in September is 67%.

Rainfall

In Cave Junction, during September, the rain falls for 5.3 days and regularly aggregates up to 0.59" (15mm) of precipitation. In Cave Junction, during the entire year, the rain falls for 135.3 days and collects up to 23.54" (598mm) of precipitation.

Snowfall

In Cave Junction, Oregon, snow does not fall in May through October.

Daylight

In Cave Junction, the average length of the day in September is 12h and 28min.
On the first day of the month, sunrise is at 6:40 am and sunset at 7:47 pm. On the last day of September, sunrise is at 7:11 am and sunset at 6:57 pm PDT.

Sunshine

The average sunshine in September is 10.4h.

UV index

The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the average person.
Note: In September, the maximum UV index of 4 translates into these guidelines:
Be vigilant - A duty to shield skin and eyes from injury exists. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation.

Frequently asked questions

What is the usual temperature for Cave Junction in September?

In Cave Junction, in September, the average high-temperature is 77.4°F (25.2°C), and the average low-temperature is 45°F (7.2°C). In August, the average heat index (a.k.a. 'apparent temperature', 'felt air temperature'), which calculates the temperature value influenced by the moisture in the air, is appraised at 89.6°F (32°C).

What is the average humidity in September?

In September, the average relative humidity is 67%.

How much does it rain in Cave Junction in September?

In September, the rain falls for 5.3 days. Throughout September, 0.59" (15mm) of precipitation is accumulated.

When it does not snow?

In Cave Junction, snow does not fall in May through October.

What is the average length of the day in September?

In September, the average day length is 12h and 28min.

What time are sunrise and sunset in September?

On the first day of September, sunrise is at 6:40 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:11 am and sunset at 6:57 pm PDT.

How long on average sun shines in September?

The average sunshine duration in September is 10.4h.

How high is the UV index in September?

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium hazard to health from unprotected exposure to UV radiation.
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
Cave Junction, OR

Average temperature in September - Cave Junction, OR
  • Average high temperature in September: 77.4°F

The warmest month (with the highest average high temperature) is August (84.7°F).
The month with the lowest average high temperature is December (46°F).

  • Average low temperature in September: 45°F

The month with the highest average low temperature is August (49.1°F).
The coldest month (with the lowest average low temperature) is December (31.5°F).

Average pressure in September
Cave Junction, OR

Average pressure in September - Cave Junction, OR
  • Average pressure in September: 30"Hg

The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is August (29.99"Hg).

Average wind speed in September
Cave Junction, OR

Average wind speed in September - Cave Junction, OR
  • Average wind speed in September: 3.3mph

The windiest month (with the highest average wind speed) is March (4mph).
The calmest month (with the lowest average wind speed) is August (3.2mph).

Average humidity in September
Cave Junction, OR

Average humidity in September - Cave Junction, OR
  • Average humidity in September: 67%

The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is August (63%).

Average rainfall in September
Cave Junction, OR

Average rainfall in September - Cave Junction, OR
  • Average rainfall in September: 0.59"

The wettest month (with the highest rainfall) is December (4.02").
The driest month (with the least rainfall) is July (0.12").

Average rainfall days in September
Cave Junction, OR

Average rainfall days in September - Cave Junction, OR
  • Average rainfall days in September: 5.3 days

The month with the highest number of rainy days is March (18.7 days).
The month with the least rainy days is August (2.5 days).

Average snowfall in September
Cave Junction, OR

Average snowfall in September - Cave Junction, OR
  • Average snowfall in September: 0"

The month with the highest snowfall is February (1.5").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in September
Cave Junction, OR

Average snowfall days in September - Cave Junction, OR
  • 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).

Average daylight in September /
Average sunshine in September
Cave Junction, OR

Average daylight in September / Average sunshine in September - Cave Junction, OR
  • 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 12min).

  • Average sunshine in September: 10h and 2min

The months with the most sunshine are July and August (Average sunshine: 11h and 48min).
The month with the least sunshine is December (Average sunshine: 4h and 42min).

Average sunshine days in September
Cave Junction, OR

Average sunshine days in September - Cave Junction, OR
  • Average sunshine days in September: 23.9 days

The month with the most sunshine days is July (26.7 days).
The month with the least sunshine days is March (10.8 days).

Average UV index in September
Cave Junction, OR

Average UV index in September - Cave Junction, OR
  • Average UV index in September: 4

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

Average cloud cover in September
Cave Junction, OR

Average cloud cover in September - Cave Junction, OR
  • Average cloud cover in September: 23

The month with the most cloud cover is March (Cloud cover 54).
The month with the least cloud cover is August (Cloud cover 16).

Average visibility in September
Cave Junction, OR

Average visibility in September - Cave Junction, OR
  • Average visibility in September: 5mi

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

Cave Junction, Oregon, USA

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