Normal weather for Vashon in September
It's pleasantly warm in September in Vashon with an average temperature of 21°C. Temperatures this month range from a low of 17°C to a high of 26°C. At night, you can expect temperatures between 10°C and 15°C.
In September, there is an average of 77 mm of precipitation, spread over 10 days. The wind speed is around 3 Bft, mostly coming from the South.
Vashon in September |
New York | ||
|---|---|---|---|
 Average Temperature |
21°C | 27°C | |
 High Temp |
26°C | 31°C | |
| Low Temp |
17°C | 21°C | |
 Total Precipitation |
77 mm | 57 mm | |
| Rainy Days |
10 days | 9 days | |
Start of September
The month of September starts in Vashon with warm temps, averaging around 24°C during the day and nights around 15°C. There’s little chance of precipitation. The weather’s mostly sunny and dry.
With the temperature difference between day and night, it’s smart to wear layers. A T-shirt, light pants or skirt, and a light jacket are great for the day. For the evening and morning, a shirt, maybe a light sweater, and thin pants are recommended.
Mid September
By mid-September, daytime temps drop to around 21°C, with nights around 13°C. During this part of the month, you might see regular precipitation, but there will also be some sunny days.
Since it cools down at night, it’s a good idea to wear layers. During the day, a shirt, maybe a light sweater, and thin pants will do. In the evening and morning, choose a light jacket, sweater or hoodie, and long pants.
End of September
By the end of September, the average daytime temperature in Vashon is around 20°C, while nighttime temps are about 12°C. A shower might pop up, but overall, the weather will be dry and sunny.
Because temperatures drop in the evening, wearing layers is recommended. During the day, a shirt, maybe a light sweater, and thin pants will do. In the evening and morning, choose a light jacket, sweater or hoodie, and long pants.
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UV index
The UV index is a maximum of 6 this month. That's a moderate to high value on the intensity scale of 1 to 11. Unprotected skin can burn within 15-25 minutes.
Is September a good time to visit Vashon?
Looking for great weather? September is a good time to be in Vashon. The temperatures are nice, and there’s not too much rain.
Temperature records for Vashon in September
Check out the climate of Vashon for all months and discover the best travel time
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Daily Temperature in September in Vashon
This chart shows the average daily high and low temperatures in September for Vashon, in degrees Celsius. The red line represents the highs, and the blue line shows the lows. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, provide the average temperatures for this month.
Daily Precipitation in September in Vashon
The chart below shows the average daily precipitation in September for Vashon, measured in millimeters over the past few years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are listed at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that it rained more often. But remember, it’s just an average, and every day can be different. Based on historical weather data for September, you can expect about 10 days of precipitation in Vashon.
Daily UV Index in September in Vashon
This chart shows the average daily UV index in September in Vashon, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in Vashon Over the Years
This chart shows the average temperature in September in Vashon, measured in degrees Celsius, over the past few years.
Total Precipitation in September in Vashon Over the Years
This chart shows the average precipitation in September in Vashon, measured in millimeters over the past years. Precipitation is always measured as water, whether it’s snow or hail.
Daily Climate in September for Vashon
Click on any day in September to get detailed info about the usual weather on that day in Vashon. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Vashon
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Average Weather in Vashon by Month
Click on a month below to see detailed weather info for Vashon. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
