Napa weather in September 2023

  • 27°C maximum daytime temperature in September in Napa27
    27°C max day temperature
  • 10 hours of sunshine per day
  • 2 days with some rainfall in September in Napa2
    2 days with some rainfall
  • 11°C minimum night-time temperature in September in Napa11
    11°C min night temperature
  • 12 hours of daylight per day in September in Napa12
    12 hours of daylight per day
  • Moderate heat & humidity in September in NapaM
    Moderate heat & humidity
  • 10 mm monthly rainfall in September in Napa10
    10 mm of monthly rainfall
  • UV (maximum) index 7 (High) in September in Napa7
    7 (High) UV index
  • Save on flights to the USA including New York & Boston
  • Fly from the UK (via Dublin) from £166.99 return
  • No Aer Lingus promo code required

Recommended for California

The September weather guide for California (Napa) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

  • Top deals & discounts
  • Napa weather overview
  • Napa climate averages by month
  • More destinations
  • Best time to go to Napa
  • Napa 5-day weather forecast

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Metric (°C / mm)  |  Imperial (°F / inches)

Back to top

More about California

How hot is it in Napa in September?

Daytime temperatures usually reach 27°C in Napa in September with moderate heat and humidity, falling to 11°C at night.

How sunny is it in Napa in September?

There are normally 10 hours of bright sunshine each day in Napa in September - that's 80% of daylight hours.

Does it ever rain in Napa in September?

There are usually 2 days with some rain in Napa in September and the average monthly rainfall is 10mm.

Napa September sunrise & sunset times

Browse the sunrise and sunset times for Napa in September 2023. Select a month to view Napa sunrise and sunset times for the next 12 months.


Date Sunrise times Sunset times
Friday, 1st September 2023 06:39 19:39
Friday, 15th September 2023 06:51 19:17
Saturday, 30th September 2023 07:04 18:54

Related posts

Popular travel offers

Explore holidays in the sun for less

Top ^