September weather forecast
Truckee, CA

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The iconic Donner Summit Bridge called the Rainbow Bridge or Route 40, in Truckee, California
The iconic Donner Summit Bridge called the Rainbow Bridge or Route 40, in Truckee, California

Weather in September

September witnesses a mild drop in temperature to 71.2°F (21.8°C), signifying the onset of the fall season. The city receives a minor snowfall of 0.16" (4mm), after three long months, hinting at a nearing winter. The leaves begin their transition from lush green to vibrant hues of red, orange, and yellow. The gusty winds start to pick up, carrying whispers of the next winter. As dusk arrives earlier, the city starts preparing for the chilling months ahead.

Temperature

The shift from August to September in Truckee, California, includes a minor decrease in the average high-temperature, lightly dropping from a warm 78.3°F (25.7°C) to a pleasant 71.2°F (21.8°C). During September, Truckee reports a marked contrast from daily peak temperatures, with an average nighttime reading of 43.9°F (6.6°C).

Humidity

The average relative humidity in September is 44%.

Rainfall

In Truckee, during September, the rain falls for 2.5 days and regularly aggregates up to 0.2" (5mm) of precipitation. In Truckee, California, during the entire year, the rain falls for 60 days and collects up to 24.41" (620mm) of precipitation.

Snowfall

Months with snowfall in Truckee are January through June, September through December. September is the first month it typically snows. Throughout September, in the average 0.6 snowfall days, it receives 0.16" (4mm) of snow. Throughout the year, in Truckee, there are 82.8 snowfall days, and 146.89" (3731mm) of snow is accumulated.

Daylight

In Truckee, the average length of the day in September is 12h and 26min.
On the first day of the month, sunrise is at 6:30 am and sunset at 7:30 pm. On the last day of September, in Truckee, sunrise is at 6:56 am and sunset at 6:44 pm PDT.

Sunshine

The average sunshine in September is 11.2h.

UV index

In Truckee, the average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a moderate threat to health from unprotected exposure to Sun's UV rays for the ordinary person.
Note: In September, an average UV index of 3 transforms into the following instructions:
Ensure safety - Imperative it is to shield skin and eyes from damage. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
Updated: Aug 23, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in September?

The average high-temperature, in September, in Truckee, is 71.2°F (21.8°C), while the average low-temperature is 43.9°F (6.6°C).

What is the average humidity in September?

In September, the average relative humidity is 44%.

How many days does it rain in September?

In September, the rain falls for 2.5 days. Throughout September, 0.2" (5mm) of precipitation is accumulated.

When does it start snowing?

September is the first month it typically snows. Throughout September, in the average 0.6 snowfall days, it receives 0.16" (4mm) of snow.

What is the average length of the day in September?

The average day length in September is 12h and 26min.

What time are sunrise and sunset in September?

On the first day of September, sunrise is at 6:30 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:56 am and sunset at 6:44 pm PDT.

How many hours of sunshine does Truckee have in September?

The average sunshine duration in September is 11.2h.

How high is the UV index in September in Truckee?

In Truckee, California, the average daily maximum UV index in September is 3. A UV Index value of 3 to 5 symbolizes a moderate vulnerability from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Truckee, CA

Average temperature in September - Truckee, CA
  • Average high temperature in September: 71.2°F

The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is December (37°F).

  • Average low temperature in September: 43.9°F

The month with the highest average low temperature is July (48.7°F).
The coldest month (with the lowest average low temperature) is December (22.1°F).

Average pressure in September
Truckee, CA

Average pressure in September - Truckee, CA
  • Average pressure in September: 29.94"Hg

The month with the highest atmospheric pressure is January (30.18"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).

Average wind speed in September
Truckee, CA

Average wind speed in September - Truckee, CA
  • Average wind speed in September: 5mph

The windiest month (with the highest average wind speed) is March (6.6mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).

Average humidity in September
Truckee, CA

Average humidity in September - Truckee, CA
  • Average humidity in September: 44%

The month with the highest relative humidity is March (80%).
The months with the lowest relative humidity are July and August (39%).

Average rainfall in September
Truckee, CA

Average rainfall in September - Truckee, CA
  • Average rainfall in September: 0.2"

The wettest month (with the highest rainfall) is February (4.37").
The driest month (with the least rainfall) is August (0.12").

Average rainfall days in September
Truckee, CA

Average rainfall days in September - Truckee, CA
  • Average rainfall days in September: 2.5 days

The month with the highest number of rainy days is May (8.9 days).
The month with the least rainy days is July (2.4 days).

Average snowfall in September
Truckee, CA

Average snowfall in September - Truckee, CA
  • Average snowfall in September: 0.16"

The month with the highest snowfall is March (30.35").
The months with the least snowfall are July and August (0").

Average snowfall days in September
Truckee, CA

Average snowfall days in September - Truckee, CA
  • Average snowfall days in September: 0.6 days

The month with the highest number of snowfall days is March (16.2 days).
The months with the least snowfall days are July and August (0 days).

Average daylight in September /
Average sunshine in September
Truckee, CA

Average daylight in September / Average sunshine in September - Truckee, CA
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).

  • Average sunshine in September: 11h and 1min

The month with the most sunshine is July (Average sunshine: 12h and 12min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).

Average sunshine days in September
Truckee, CA

Average sunshine days in September - Truckee, CA
  • Average sunshine days in September: 26.5 days

The month with the most sunshine days is July (27.1 days).
The month with the least sunshine days is March (12.8 days).

Average UV index in September
Truckee, CA

Average UV index in September - Truckee, CA
  • 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 2).

Average cloud cover in September
Truckee, CA

Average cloud cover in September - Truckee, CA
  • Average cloud cover in September: 9

The month with the most cloud cover is March (Cloud cover 40).
The month with the least cloud cover is July (Cloud cover 6).

Average visibility in September
Truckee, CA

Average visibility in September - Truckee, CA
  • Average visibility in September: 6mi

The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February, March and December (5mi).

Truckee, California, USA

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