Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The arrival of September corresponds with a light shift in temperature, down from a pleasant 72.1°F (22.3°C) in August to a comfortable 65.8°F (18.8°C). September nights are characterized by a notable drop from daytime highs, with an average low-temperature of 41.5°F (5.3°C).Humidity
In Mammoth Lakes, the average relative humidity in September is 38%.Rainfall
In September, the rain falls for 1.9 days. Throughout September, 0.12" (3mm) of precipitation is accumulated. In Mammoth Lakes, California, during the entire year, the rain falls for 47.7 days and collects up to 4.92" (125mm) of precipitation.Snowfall
Months with snowfall are January through June, September through December. September is the first month it typically snows. Throughout September, in the average 0.7 snowfall days, it receives 0.12" (3mm) of snow. In Mammoth Lakes, during the entire year, snow falls for 60.8 days and aggregates up to 28.58" (726mm) of snow.Daylight
The average length of the day in September is 12h and 25min.On the first day of the month, sunrise is at 6:26 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:51 am and sunset at 6:39 pm PDT.
Sunshine
In Mammoth Lakes, the average sunshine in September is 11h.UV index
In Mammoth Lakes, the average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for ordinary individuals.Note: In September, the maximum UV index of 3 translates into these guidelines:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Be aware! The reflective nature of snow can magnify the Sun's UV radiation almost twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
How much does it rain in September?
When does it start snowing?
How many hours of daylight does Mammoth Lakes have in September?
When are sunrise and sunset in September?
How many hours of sunshine does Mammoth Lakes have in September?
What is the UV index reading in September?
Average temperature in September
Mammoth Lakes, CA
- Average high temperature in September: 65.8°F
The warmest month (with the highest average high temperature) is July (73.4°F).
The month with the lowest average high temperature is February (34°F).
- Average low temperature in September: 41.5°F
The month with the highest average low temperature is July (48.2°F).
The coldest month (with the lowest average low temperature) is February (14.9°F).
Average pressure in September
Mammoth Lakes, CA
- Average pressure in September: 29.93"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in September
Mammoth Lakes, CA
- Average wind speed in September: 5.2mph
The windiest month (with the highest average wind speed) is March (6.9mph).
The calmest months (with the lowest average wind speed) are July and August (4.9mph).
Average humidity in September
Mammoth Lakes, CA
- Average humidity in September: 38%
The month with the highest relative humidity is February (76%).
The month with the lowest relative humidity is August (34%).
Average rainfall in September
Mammoth Lakes, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is February (0.94").
The driest months (with the least rainfall) are August and October (0.08").
Average rainfall days in September
Mammoth Lakes, CA
- Average rainfall days in September: 1.9 days
The month with the highest number of rainy days is April (6.3 days).
The month with the least rainy days is August (1.8 days).
Average snowfall in September
Mammoth Lakes, CA
- Average snowfall in September: 0.12"
The month with the highest snowfall is February (5.67").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Mammoth Lakes, CA
- Average snowfall days in September: 0.7 days
The month with the highest number of snowfall days is March (11.3 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Mammoth Lakes, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 11h and 0min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 6h and 18min).
Average sunshine days in September
Mammoth Lakes, CA
- Average sunshine days in September: 25.9 days
The month with the most sunshine days is October (27.3 days).
The month with the least sunshine days is March (18.2 days).
Average UV index in September
Mammoth Lakes, CA
- Average UV index in September: 3
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).
Average cloud cover in September
Mammoth Lakes, CA
- Average cloud cover in September: 8
The month with the most cloud cover is March (Cloud cover 30).
The month with the least cloud cover is August (Cloud cover 7).
Average visibility in September
Mammoth Lakes, CA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Mammoth Lakes, California, USA
Weather forecast for your location
2. Allow the app to use your location