Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
September records an average high-temperature of a still moderately hot 80.2°F (26.8°C), indicating a minor variation from the preceding month. Alviso receives a consistent average low-temperature of 55.6°F (13.1°C) in September, a substantial dip from the day's heat.Humidity
The average relative humidity in September is 59%.Rainfall
In Alviso, California, in September, during 2.2 rainfall days, 0.08" (2mm) of precipitation is typically accumulated. In Alviso, during the entire year, the rain falls for 52.8 days and collects up to 4.06" (103mm) of precipitation.Daylight
The average length of the day in September in Alviso is 12h and 25min.On the first day of the month, sunrise is at 6:39 am and sunset at 7:36 pm. On the last day of September, sunrise is at 7:03 am and sunset at 6:51 pm PDT.
Sunshine
In September, the average sunshine in Alviso is 11.2h.UV index
In Alviso, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum daily UV index of 5 in September interprets into the following recommendations:
Be mindful. Individuals with a lighter skin tone may suffer burns in less than 30 minutes. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Frequently asked questions
What is the temperature in September in Alviso?
What is the average humidity in September in Alviso?
How much does it rain in Alviso in September?
How many hours of daylight does Alviso have in September?
When is the sunrise / sunset in September in Alviso?
How long on average sun shines in September in Alviso?
What is the UV index intensity in September in Alviso?
Average temperature in September
Alviso, CA
- Average high temperature in September: 80.2°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is December (56.3°F).
- Average low temperature in September: 55.6°F
The month with the highest average low temperature is August (56.8°F).
The coldest months (with the lowest average low temperature) are January and December (42.6°F).
Average pressure in September
Alviso, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in September
Alviso, CA
- Average wind speed in September: 4.4mph
The windiest month (with the highest average wind speed) is May (5.8mph).
The calmest months (with the lowest average wind speed) are October and November (4.3mph).
Average humidity in September
Alviso, CA
- Average humidity in September: 59%
The month with the highest relative humidity is March (73%).
The month with the lowest relative humidity is July (58%).
Average rainfall in September
Alviso, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is March (0.83").
The driest months (with the least rainfall) are June, July and August (0.04").
Average rainfall days in September
Alviso, CA
- Average rainfall days in September: 2.2 days
The month with the highest number of rainy days is March (9.9 days).
The month with the least rainy days is August (0.4 days).
Average daylight in September /
Average sunshine in September
Alviso, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 11h and 1min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).
Average sunshine days in September
Alviso, CA
- Average sunshine days in September: 26.8 days
The month with the most sunshine days is August (29.6 days).
The month with the least sunshine days is March (19.5 days).
Average UV index in September
Alviso, CA
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in September
Alviso, CA
- Average cloud cover in September: 10
The month with the most cloud cover is March (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 5).
Average visibility in September
Alviso, 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).
Alviso, California, USA
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