September weather forecast and climate
Mount Shasta, CA

The Lake Siskiyou on the base of Mount Shasta in California, and a view of the planted forest, the far suspension bridge, and snowy mountain peak
The Lake Siskiyou on the base of Mount Shasta in California, and a view of the planted forest, the far suspension bridge, and snowy mountain peak

Weather in September

The first month of the autumn, September, is also a moderately hot month in Mount Shasta, California, with average temperature varying between 76.1°F (24.5°C) and 46.4°F (8°C).

Temperature

In Mount Shasta, the average high-temperature marginally drops, from 83.5°F (28.6°C) in August, to a still moderately hot 76.1°F (24.5°C). In September, the average low-temperature is 46.4°F (8°C).

Humidity

The average relative humidity is 50%.

Rainfall

In September, in Mount Shasta, the rain falls for 4.1 days. Throughout September, 0.47" (12mm) of precipitation is accumulated. Throughout the year, there are 90.7 rainfall days, and 26.38" (670mm) of precipitation is accumulated.

Snowfall

January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.2" (5mm) of snow. Throughout the year, there are 50.2 snowfall days, and 81.42" (2068mm) of snow is accumulated.

Daylight

In Mount Shasta, the average length of the day in September is 12.4h.

Sunshine

In September, the average sunshine in Mount Shasta is 11.1h.

UV index

The average daily maximum UV index in Mount Shasta is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to the Sun's UV rays for average individuals.
Note: The average daily UV index of 4 transform into the following instructions:
Take precautions - Protection against the skin and eye damage is obliged. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.
[Resources]

FAQ

What is the temperature in September in Mount Shasta?

In September, the average high-temperature is 76.1°F (24.5°C), and the average low-temperature is 46.4°F (8°C).

What is the average humidity in September in Mount Shasta?

The average relative humidity in September in Mount Shasta, California, is 50%.

How many days does it rain in September in Mount Shasta?

In Mount Shasta, California, in September, during 4.1 rainfall days, 0.47" (12mm) of precipitation is typically accumulated.

When does it start snowing in Mount Shasta?

September is the first month it typically snows in Mount Shasta. Throughout September, in the average 0.2 snowfall days, it receives 0.2" (5mm) of snow.

What is the average length of the day in September in Mount Shasta?

The average length of the day in September in Mount Shasta is 12.4h.

How long on average sun shines in September in Mount Shasta?

The average sunshine in September in Mount Shasta, California, is 11.1h.

What is the UV index reading in September in Mount Shasta?

The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium health risk from the exposure to the Sun's UV rays.

Average temperature in September
Mount Shasta, CA

Average temperature in September - Mount Shasta, CA
  • Average high temperature in September: 76.1°F

The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is December (40.8°F).

  • Average low temperature in September: 46.4°F

The month with the highest average low temperature is July (52.2°F).
The coldest month (with the lowest average low temperature) is December (27.1°F).

[Resources]

Average pressure in September
Mount Shasta, CA

Average pressure in September - Mount Shasta, CA
  • Average pressure in September: 29.96"

The month with the highest atmospheric pressure is January (30.17").
Months with the lowest atmospheric pressure are June and August (29.94").

[Resources]

Average wind speed in September
Mount Shasta, CA

Average wind speed in September - Mount Shasta, CA
  • Average wind speed in September: 4.5mph

The windiest month (with the highest average wind speed) is March (5.8mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).

[Resources]

Average humidity in September
Mount Shasta, CA

Average humidity in September - Mount Shasta, CA
  • Average humidity in September: 50%

The month with the highest relative humidity is March (81%).
The month with the lowest relative humidity is August (45%).

[Resources]

Average rainfall in September
Mount Shasta, CA

Average rainfall in September - Mount Shasta, CA
  • Average rainfall in September: 0.47"

The wettest month (with the highest rainfall) is March (4.69").
The driest month (with the least rainfall) is July (0.16").

[Resources]

Average rainfall days in September
Mount Shasta, CA

Average rainfall days in September - Mount Shasta, CA
  • Average rainfall days in September: 4.1 days

The month with the highest number of rainy days is March (12.3 days).
The month with the least rainy days is August (2.3 days).

[Resources]

Average snowfall in September
Mount Shasta, CA

Average snowfall in September - Mount Shasta, CA
  • Average snowfall in September: 0.2"

The month with the highest snowfall is January (19.21").
Months with the least snowfall are June, July and August (0").

[Resources]

Average snowfall days in September
Mount Shasta, CA

Average snowfall days in September - Mount Shasta, CA
  • Average snowfall days in September: 0.2 days

The month with the highest number of snowfall days is December (10.9 days).
Months with the least snowfall days are July and August (0 days).

[Resources]

Average daylight in September /
Average sunshine in September
Mount Shasta, CA

Average daylight in September / Average sunshine in September - Mount Shasta, CA
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 15.1h).
The month with the shortest days is December (Average daylight: 9.2h).

  • Average sunshine in September: 11.1h

The month with the most sunshine is July (Average sunshine: 12.1h).
The month with the least sunshine is December (Average sunshine: 5.4h).

[Resources]

Average sunshine days in September
Mount Shasta, CA

Average sunshine days in September - Mount Shasta, CA
  • Average sunshine days in September: 24 days

Months with the most sunshine days are July and August (25.7 days).
The month with the least sunshine days is March (12.3 days).

[Resources]

Average UV index in September
Mount Shasta, CA

Average UV index in September - Mount Shasta, CA
  • Average UV index in September: 4

Months with the highest UV index are June and July (UV index 6).
Months with the lowest UV index are January, February, March, November and December (UV index 2).

[Resources]

Average cloud cover in September
Mount Shasta, CA

Average cloud cover in September - Mount Shasta, CA
  • Average cloud cover in September: 12

The month with the most cloud cover is March (Cloud cover 45).
The month with the least cloud cover is August (Cloud cover 6).

[Resources]

Average visibility in September
Mount Shasta, CA

Average visibility in September - Mount Shasta, CA
  • Average visibility in September: 6mi

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

[Resources]