September weather forecast and climate
Opal Cliffs, CA

Weather in September

The first month of the autumn, September, is still a pleasant month in Opal Cliffs, California, with average temperature fluctuating between 55.2°F (12.9°C) and 73°F (22.8°C).

Temperature

The warmest months are August and September, with an average high-temperature of 73°F (22.8°C).

Humidity

In Opal Cliffs, the average relative humidity is 70%.

Rainfall

In Opal Cliffs, during September, the rain falls for 2.7 days and regularly aggregates up to 0.12" (3mm) of precipitation. In Opal Cliffs, during the entire year, the rain falls for 77.9 days and collects up to 14.45" (367mm) of precipitation.

Ocean temperature

Months with the warmest seawater are August and September, with an average ocean temperature of 58.1°F (14.5°C).
Note: At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

Daylight

In Opal Cliffs, the average length of the day is 12.4h.

Sunshine

In September, the average sunshine in Opal Cliffs is 10.9h.

UV index

Months with the highest UV index are June through September, with an average maximum UV index of 5. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to the Sun's UV rays for the average person.
Note: In September, the average maximum UV index of 5 translate into the following recommendations:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.
[Resources]

FAQ

What is the warmest month in Opal Cliffs?

August and September, with an average high-temperature of 73°F (22.8°C), are warmest months in Opal Cliffs.

What is the temperature in September in Opal Cliffs?

In September, the average high-temperature is 73°F (22.8°C), and the average low-temperature is 55.2°F (12.9°C).

What is the average humidity in September in Opal Cliffs?

The average relative humidity in September is 70%.

How many days does it rain in September in Opal Cliffs?

In Opal Cliffs, California, during September, the rain falls for 2.7 days and regularly aggregates up to 0.12" (3mm) of precipitation.

What are the months with the warmest ocean in Opal Cliffs?

August and September, with an average ocean temperature of 58.1°F (14.5°C), are months with the warmest seawater in Opal Cliffs, California.

How cold is the water in September in Opal Cliffs?

In Opal Cliffs, the average seawater temperature in September is 58.1°F (14.5°C). At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

How many hours of daylight does Opal Cliffs have in September?

The average length of the day in September in Opal Cliffs is 12.4h.

How long on average sun shines in September in Opal Cliffs?

In September, the average sunshine in Opal Cliffs, California, is 10.9h.

What is the month with the highest UV index in Opal Cliffs?

Months with the highest UV index in Opal Cliffs are June through September, with an average maximum UV index of 5.

What is the UV index intensity in September in Opal Cliffs?

In Opal Cliffs, California, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium health risk from unprotected exposure to the UV radiation.

Average temperature in September
Opal Cliffs, CA

Average temperature in September - Opal Cliffs, CA
  • Average high temperature in September: 73°F

The warmest months (with the highest average high temperature) are August and September (73°F).
The month with the lowest average high temperature is December (57.2°F).

  • Average low temperature in September: 55.2°F

The month with the highest average low temperature is September (55.2°F).
The coldest month (with the lowest average low temperature) is February (45.5°F).

[Resources]

Average pressure in September
Opal Cliffs, CA

Average pressure in September - Opal Cliffs, CA
  • Average pressure in September: 29.92"

The month with the highest atmospheric pressure is January (30.13").
The month with the lowest atmospheric pressure is September (29.92").

[Resources]

Average wind speed in September
Opal Cliffs, CA

Average wind speed in September - Opal Cliffs, CA
  • Average wind speed in September: 5.7mph

The windiest month (with the highest average wind speed) is April (7.4mph).
The calmest months (with the lowest average wind speed) are July and August (5.5mph).

[Resources]

Average humidity in September
Opal Cliffs, CA

Average humidity in September - Opal Cliffs, CA
  • Average humidity in September: 70%

The month with the highest relative humidity is March (75%).
The month with the lowest relative humidity is October (68%).

[Resources]

Average rainfall in September
Opal Cliffs, CA

Average rainfall in September - Opal Cliffs, CA
  • Average rainfall in September: 0.12"

The wettest month (with the highest rainfall) is December (2.8").
The driest months (with the least rainfall) are July and August (0.04").

[Resources]

Average rainfall days in September
Opal Cliffs, CA

Average rainfall days in September - Opal Cliffs, CA
  • Average rainfall days in September: 2.7 days

The month with the highest number of rainy days is March (13.4 days).
The month with the least rainy days is August (1.2 days).

[Resources]

Average sea temperature in September
Opal Cliffs, CA

Average sea temperature in September - Opal Cliffs, CA
  • Average sea temperature in September: 58.1°F

The best months for swimming (with the highest average sea temperature) are August and September (58.1°F).
The coldest month (with the lowest average sea temperature) is April (53.8°F).

[Resources]

Average daylight in September /
Average sunshine in September
Opal Cliffs, CA

Average daylight in September / Average sunshine in September - Opal Cliffs, CA
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 14.7h).
The month with the shortest days is December (Average daylight: 9.7h).

  • Average sunshine in September: 10.9h

The month with the most sunshine is July (Average sunshine: 11.7h).
The month with the least sunshine is December (Average sunshine: 5.8h).

[Resources]

Average sunshine days in September
Opal Cliffs, CA

Average sunshine days in September - Opal Cliffs, CA
  • Average sunshine days in September: 26.3 days

The month with the most sunshine days is August (27.8 days).
The month with the least sunshine days is March (16.4 days).

[Resources]

Average UV index in September
Opal Cliffs, CA

Average UV index in September - Opal Cliffs, CA
  • Average UV index in September: 5

Months with the highest UV index are June, July, August and September (UV index 5).
Months with the lowest UV index are February and November (UV index 3).

[Resources]

Average cloud cover in September
Opal Cliffs, CA

Average cloud cover in September - Opal Cliffs, CA
  • Average cloud cover in September: 15

The month with the most cloud cover is March (Cloud cover 38).
Months with the least cloud cover are July and September (Cloud cover 15).

[Resources]

Average visibility in September
Opal Cliffs, CA

Average visibility in September - Opal Cliffs, CA
  • Average visibility in September: 6mi

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

[Resources]