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 snowfall in September
- Average snowfall 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
With the onset of September, Foster City's climate undergoes a slight change as the average high-temperature moves from a warm 75.7°F (24.3°C) in August to a comfortable 67.6°F (19.8°C). Foster City reports a consistent average low-temperature of 48.6°F (9.2°C) throughout September nights.Humidity
In September, the average relative humidity is 81%.Rainfall
In Foster City, in September, it is raining for 11.5 days, with typically 1.81" (46mm) of accumulated precipitation. Throughout the year, in Foster City, there are 137.4 rainfall days, and 22.83" (580mm) of precipitation is accumulated.Snowfall
In Foster City, snow does not fall in June through September.Daylight
In September, the average length of the day in Foster City is 12h and 31min.On the first day of September, sunrise is at 6:12 am and sunset at 7:28 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 6:32 pm CDT.
Sunshine
In September, the average sunshine in Foster City is 8.1h.UV index
The average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for the average person.Note: A typical high UV index of 3 in September suggests the following recommendations:
Undertake precautions - It is suggested to shield oneself from sunburn. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
Does it snow in September?
What is the average length of the day in September?
When are sunrise and sunset in September?
How many hours of sunshine does Foster City have in September?
What is the UV index intensity in September?
Average temperature in September
Foster City, MI
- Average high temperature in September: 67.6°F
The warmest month (with the highest average high temperature) is July (77.5°F).
The month with the lowest average high temperature is January (21°F).
- Average low temperature in September: 48.6°F
The month with the highest average low temperature is July (56.8°F).
The coldest month (with the lowest average low temperature) is January (10.2°F).
Average pressure in September
Foster City, MI
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is March (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Foster City, MI
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is April (8.3mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in September
Foster City, MI
- Average humidity in September: 81%
The month with the highest relative humidity is February (90%).
The month with the lowest relative humidity is May (72%).
Average rainfall in September
Foster City, MI
- Average rainfall in September: 1.81"
The wettest month (with the highest rainfall) is June (2.6").
The driest month (with the least rainfall) is January (1.14").
Average rainfall days in September
Foster City, MI
- Average rainfall days in September: 11.5 days
The months with the highest number of rainy days are May, June and July (15.3 days).
The month with the least rainy days is February (5.7 days).
Average snowfall in September
Foster City, MI
- Average snowfall in September: 0"
The month with the highest snowfall is February (9.09").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Foster City, MI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (20.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Foster City, MI
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in September: 8h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is February (Average sunshine: 2h and 48min).
Average sunshine days in September
Foster City, MI
- Average sunshine days in September: 15.5 days
The month with the most sunshine days is September (15.5 days).
The month with the least sunshine days is February (9.1 days).
Average UV index in September
Foster City, MI
- Average UV index in September: 3
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 1).
Average cloud cover in September
Foster City, MI
- Average cloud cover in September: 42
The month with the most cloud cover is February (Cloud cover 70).
The month with the least cloud cover is July (Cloud cover 34).
Average visibility in September
Foster City, MI
- Average visibility in September: 5mi
The months with the highest visibility are May, June, October and November (6mi).
The month with the lowest visibility is February (4mi).
Foster City, Michigan, USA
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