Normal weather for Napa in September
It's warm in September in Napa with an average temperature of 28°C. Temperatures this month range from a low of 24°C to a high of 31°C. At night, you can expect temperatures between 10°C and 14°C.
According to weather history, there is only 3,1 mm of precipitation in September. The wind speed is around 4 Bft, mostly coming from the Southwest.
Napa in September |
New York | ||
|---|---|---|---|
 Average Temperature |
28°C | 27°C | |
 High Temp |
31°C | 31°C | |
| Low Temp |
24°C | 21°C | |
 Total Precipitation |
3,1 mm | 57 mm | |
| Rainy Days |
1 day | 9 days | |
Start of September
The month of September starts in Napa with hot temps, averaging around 29°C during the day and nights around 14°C. No precipitation expected at the start of the month; it’ll be sunny.
With the temperature difference between day and night, it’s smart to wear layers. For the daytime, light clothing like shorts or a dress, and a hat and sunglasses are perfect. 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 27°C, with nights around 13°C. No precipitation expected during this period, so you can enjoy plenty of sunshine.
Since it cools down at night, it’s a good idea to wear layers. For the daytime, light clothing like shorts or a dress, and a hat and sunglasses are perfect. 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 Napa is around 28°C, while nighttime temps are about 12°C. No precipitation expected at the end of the month; it’ll be mostly sunny.
Because temperatures drop in the evening, wearing layers is recommended. For the daytime, light clothing like shorts or a dress, and a hat and sunglasses are perfect. In the evening and morning, choose a light jacket, sweater or hoodie, and long pants.
UV index
The UV index is a maximum of 8 this month. That's a very high value on the intensity scale of 1 to 11. Unprotected skin can burn within 10-15 minutes.
Is September a good time to visit Napa?
Looking for great weather? September is a good time to be in Napa. The temperatures are nice, and there’s not too much rain.
Temperature records for Napa in September
Check out the climate of Napa for all months and discover the best travel time
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Daily Temperature in September in Napa
This chart shows the average daily high and low temperatures in September for Napa, 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 Napa
The chart below shows the average daily precipitation in September for Napa, 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 1 day of precipitation in Napa.
Daily UV Index in September in Napa
This chart shows the average daily UV index in September in Napa, 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 Napa Over the Years
This chart shows the average temperature in September in Napa, measured in degrees Celsius, over the past few years.
Total Precipitation in September in Napa Over the Years
This chart shows the average precipitation in September in Napa, measured in millimeters over the past years. Precipitation is always measured as water, whether it’s snow or hail.
Daily Climate in September for Napa
Click on any day in September to get detailed info about the usual weather on that day in Napa. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Napa
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Average Weather in Napa by Month
Click on a month below to see detailed weather info for Napa. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
