September weather forecastGarden Grove, CA
September
Weather in September
September, the first month of the autumn in Garden Grove, is still a warm month, with an average temperature varying between 79.7°F (26.5°C) and 64.8°F (18.2°C).Temperature
The onset of September marks an average high-temperature of a still warm 79.7°F (26.5°C), hardly differing from August's 80.2°F (26.8°C). During the month of September, the temperature generally drops to a low average of 64.8°F (18.2°C).Humidity
The average relative humidity in September is 62%.Rainfall
In Garden Grove, in September, during 1.8 rainfall days, 0.08" (2mm) of precipitation is typically accumulated. In Garden Grove, during the entire year, the rain falls for 39.3 days and collects up to 2.95" (75mm) of precipitation.Daylight
The average length of the day in September in Garden Grove is 12h and 22min.On the first day of September, sunrise is at 6:26 am and sunset at 7:16 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:36 pm PDT.
Sunshine
In September, the average sunshine is 10.6h.UV index
June through September, with an average maximum UV index of 6, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high health vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: During September, 6 as the daily maximum UV index converts into the following advice:
Resist extreme sun exposure. Guarding against solar damage is essential. Stay out of direct sunlight between 10 a.m. and 4 p.m., when UV radiation is most intense, and remember that not all shade structures provide complete protection. 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.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Garden Grove, CA
- Average high temperature in September: 79.7°F
The warmest month (with the highest average high temperature) is August (80.2°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 (65.1°F).
The coldest month (with the lowest average low temperature) is February (51.4°F).
Average pressure in September
Garden Grove, 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
Garden Grove, CA
- Average wind speed in September: 4.9mph
The windiest month (with the highest average wind speed) is April (6.3mph).
The calmest month (with the lowest average wind speed) is September (4.9mph).
Average humidity in September
Garden Grove, CA
- Average humidity in September: 62%
The month with the highest relative humidity is June (69%).
The month with the lowest relative humidity is November (54%).
Average rainfall in September
Garden Grove, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is December (0.71").
The driest month (with the least rainfall) is June (0").
Average rainfall days in September
Garden Grove, CA
- Average rainfall days in September: 1.8 days
The month with the highest number of rainy days is March (6 days).
The month with the least rainy days is June (0.9 days).
Average daylight in September /
Average sunshine in September
Garden Grove, CA
- Average daylight in September: 12h and 24min
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 36min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in September
Garden Grove, CA
- Average sunshine days in September: 26.3 days
The month with the most sunshine days is June (28.1 days).
The month with the least sunshine days is February (22.1 days).
Average UV index in September
Garden Grove, 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
Garden Grove, CA
- Average cloud cover in September: 9
The months with the most cloud cover are March and December (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 6).
Average visibility in September
Garden Grove, 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).





