Yosemite National Park
California, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Yosemite National Park, CA

Part of Merced River in the valley below the Yosemite National Park Mountains, California, with clear blue skies
Part of Merced River in the valley below the Yosemite National Park Mountains, California, with clear blue skies
September is one of the best times to visit Yosemite with mild temperatures, cloudless skies, and an absence of moisture and rain. Temperatures mostly range from 47°F (8.3°C) to 83°F (28.3°C) with warm days and temperate nights.
Clear night skies with fantastic stargazing opportunities are one of the best features of Yosemite trips. Sunny days often touch 95°F (35°C), and the shuttle service along major trails is a nice way to avoid the heat.
The crowds start to taper off by late September, providing late summer tourists great opportunities to enjoy the beautiful scenery at peace.

What is the temperature in September in Yosemite National Park?

In Yosemite National Park, California, in September, the average high-temperature is 83.5°F (28.6°C), and the average low-temperature is 46.8°F (8.2°C).

How many days does it rain in September in Yosemite National Park?

In Yosemite National Park, California, in September, during 2 rainfall days, 0.7" (16.8mm) of precipitation is typically accumulated.

Does it snow in Yosemite National Park in September?

In Yosemite National Park, in September, it doesn't snow. In October, it regularly snows.

When it does not snow in Yosemite National Park?

June through September are months without snowfall in Yosemite National Park.

How many hours of daylight does Yosemite National Park have in September?

The average length of the day in September in Yosemite National Park is 12.4h.

How long on average sun shines in September in Yosemite National Park?

In Yosemite National Park, the average sunshine in September is 10h.

How high is the UV index in September in Yosemite National Park?

The average daily maximum UV index in September is 8. A UV Index reading of 8 to 10 represents a very high health vulnerability from the exposure to the Sun's UV radiation.
Average temperature in September - Yosemite National Park, CA
  • Average high temperature in September: 83.5°F

The warmest month (with the highest average high temperature) is July (89.9°F).
The month with the lowest average high temperature is January (47.2°F).

  • Average low temperature in September: 46.7°F

The month with the highest average low temperature is July (53.2°F).
The coldest month (with the lowest average low temperature) is January (25.6°F).

Average rainfall in September - Yosemite National Park, CA
  • Average rainfall in September: 0.7"

The wettest month (with the highest rainfall) is January (6.5").
The driest month (with the lowest rainfall) is August (0.2").

Average rainfall days in September - Yosemite National Park, CA
  • Average rainfall days in September: 2 days

The month with the highest number of rainy days is March (10 days).
Months with the lowest number of rainy days are July and August (1 days).

Average snowfall in September - Yosemite National Park, CA
  • Average snowfall in September: 0"

The month with the highest snowfall is January (16.2").
Months with the lowest snowfall are June, July, August and September (0").

Average daylight in September / Average sunshine in September - Yosemite National Park, CA
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 14.8h).
The month with shortest days is December (Average daylight: 9.6h).

  • Average sunshine in September: 10h

The month with most sunshine is July (Average sunshine: 12h).
Months with least sunshine are January and December (Average sunshine: 6).

Average UV index in September - Yosemite National Park, CA
  • Average UV index in September: 8

The month with the highest UV index is July (UV index 11).
Months with the lowest UV index are January and December (UV index 2).