September weather forecast
Long Beach, CA

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A colorful sunset sky over the Pacific Ocean in Long Beach, California
A colorful sunset sky over the Pacific Ocean in Long Beach, California

Weather in September

September marks the advent of fall in Long Beach, California. The weather takes a comfortable turn, becoming significantly less hot and paving the way for a lovely autumn. The month showcases a blend of warm and cool temperatures, varying from 64.8°F (18.2°C) to 78.8°F (26°C). As October surfaces, it continues the occasional rainfall brought by September, making it a colorful month filled with fall foliage. September's perfectly balanced weather makes it a favorite among those who appreciate light breezes and mild temperatures.

Temperature

Long Beach experiences a subtle adjustment in high-temperatures to a still moderately hot 78.8°F (26°C) with the onset of September, maintaining near parity with August's 79.5°F (26.4°C). An average low-temperature of 64.8°F (18.2°C) is recorded in the month of September in Long Beach.

Humidity

In September, the average relative humidity is 63%.

Rainfall

In September, the rain falls for 3.3 days. Throughout September, 0.24" (6mm) of precipitation is accumulated. In Long Beach, during the entire year, the rain falls for 47.2 days and collects up to 5.59" (142mm) of precipitation.

Ocean temperature

In September, the average ocean temperature is 66.7°F (19.3°C).
Note: Swimming is not an enjoyable activity for the majority when the water is at 66.7°F (19.3°C). The difficulty of controlling breathing increases as the temperature dips from 69.8°F (21°C) to 59°F (15°C).

Daylight

In Long Beach, the average length of the day in September is 12h and 22min.
On the first day of September in Long Beach, sunrise is at 6:27 am and sunset at 7:17 pm. On the last day of the month, sunrise is at 6:47 am and sunset at 6:37 pm PDT.

Sunshine

The average sunshine in September is 10.6h.

UV index

June through September, with an average maximum UV index of 6, are months with the highest UV index in Long Beach, California. A UV Index of 6 to 7 symbolizes a high health risk from unsafe exposure to UV radiation for the average person.
Note: In September, the maximum UV index of 6 translates into these guidelines:
Embrace precautions and observe sun safety norms. Evasion of sunburn is a necessity. Remember that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. Make an effort to avoid direct sun exposure during these hours. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays.

Frequently asked questions

What are September temperatures in Long Beach?

The high-temperature, in September, in Long Beach, records 78.8°F (26°C), while the low-temperature is 64.8°F (18.2°C).

What is the average humidity in September in Long Beach?

In Long Beach, the average relative humidity in September is 63%.

How many days does it rain in September in Long Beach?

In Long Beach, in September, during 3.3 rainfall days, 0.24" (6mm) of precipitation is typically accumulated.

How cold is the water in September in Long Beach?

In Long Beach, in September, the average water temperature is 66.7°F (19.3°C). Swimming in 66.7°F (19.3°C) is not enjoyable for the majority. Controlling breathing becomes progressively more difficult as surface water temperature decreases below 69.8°F (21°C).

How many hours of daylight does Long Beach have in September?

In Long Beach, the average day length in September is 12h and 22min.

What time are sunrise and sunset in September in Long Beach?

On the first day of September in Long Beach, California, sunrise is at 6:27 am and sunset at 7:17 pm. On the last day of the month, sunrise is at 6:47 am and sunset at 6:37 pm PDT.

How long on average sun shines in September in Long Beach?

The average sunshine duration in September is 10.6h.

What are the months with the highest UV index in Long Beach?

The months with the highest UV index are June through September, with an average maximum UV index of 6.

How high is the UV index in September in Long Beach?

In Long Beach, California, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high hazard to health from exposure to the Sun's UV radiation.
Average humidity
Average rainfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Long Beach, CA

Average temperature in September - Long Beach, CA
  • Average high temperature in September: 78.8°F

The warmest month (with the highest average high temperature) is August (79.5°F).
The month with the lowest average high temperature is December (63.5°F).

  • Average low temperature in September: 64.8°F

The month with the highest average low temperature is August (64.9°F).
The coldest month (with the lowest average low temperature) is February (52°F).

Average pressure in September
Long Beach, CA

Average pressure in September - Long Beach, CA
  • Average pressure in September: 29.89"Hg

The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are June and September (29.89"Hg).

Average wind speed in September
Long Beach, CA

Average wind speed in September - Long Beach, CA
  • Average wind speed in September: 5mph

The windiest month (with the highest average wind speed) is April (6.5mph).
The calmest months (with the lowest average wind speed) are September and October (5mph).

Average humidity in September
Long Beach, CA

Average humidity in September - Long Beach, CA
  • Average humidity in September: 63%

The month with the highest relative humidity is June (71%).
The month with the lowest relative humidity is November (55%).

Average rainfall in September
Long Beach, CA

Average rainfall in September - Long Beach, CA
  • Average rainfall in September: 0.24"

The wettest month (with the highest rainfall) is December (1.14").
The driest month (with the least rainfall) is June (0.08").

Average rainfall days in September
Long Beach, CA

Average rainfall days in September - Long Beach, CA
  • Average rainfall days in September: 3.3 days

The month with the highest number of rainy days is March (6 days).
The month with the least rainy days is June (1.8 days).

Average sea temperature in September
Long Beach, CA

Average sea temperature in September - Long Beach, CA
  • Average sea temperature in September: 66.7°F

The best months for swimming (with the highest average sea temperature) are July and August (67.9°F).
The coldest month (with the lowest average sea temperature) is January (58.3°F).

Average daylight in September /
Average sunshine in September
Long Beach, CA

Average daylight in September / Average sunshine in September - Long Beach, CA
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 10h and 0min).

  • Average sunshine in September: 10h and 4min

The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The months with the least sunshine are January, February and December (Average sunshine: 6h and 48min).

Average sunshine days in September
Long Beach, CA

Average sunshine days in September - Long Beach, CA
  • Average sunshine days in September: 22.7 days

The month with the most sunshine days is January (25.7 days).
The month with the least sunshine days is June (20.8 days).

Average UV index in September
Long Beach, CA

Average UV index in September - Long Beach, CA
  • Average UV index in September: 6

The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 4).

Average cloud cover in September
Long Beach, CA

Average cloud cover in September - Long Beach, CA
  • Average cloud cover in September: 9

The months with the most cloud cover are March and December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 7).

Average visibility in September
Long Beach, CA

Average visibility in September - Long Beach, CA
  • 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).

Long Beach, California, USA

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