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 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
At the onset of September, Julian records an average high-temperature of a moderately hot 84.2°F (29°C), showing little deviation from the preceding month. Throughout September, Julian witnesses a nighttime temperature average of 62.8°F (17.1°C).Heat index
For September, the heat index is calculated to be a hot 86°F (30°C). When exposure and activity are sustained, they could induce fatigue, with a chance of heat cramps.Regarding the heat index, one should be aware it's determined by shaded settings and mild winds. With direct sunlight, the heat index could increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', is an index that combines air temperature and relative humidity to determine the human-perceived temperature equivalent. The individual's impression of temperature can be affected by numerous factors such as metabolic variations, physical exertion, and attire. It is noteworthy that being in direct sunlight can enhance the weather's impact, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular significance for children. Typically, young kids are at a higher risk than adults since they sweat less. Also, the larger skin surface in proportion to their small bodies and the heightened heat production due to their active nature adds to their vulnerability.
Humidity
The average relative humidity in September is 53%.Rainfall
In Julian, during September, the rain falls for 5.5 days and regularly aggregates up to 0.51" (13mm) of precipitation. In Julian, during the entire year, the rain falls for 62 days and collects up to 6.38" (162mm) of precipitation.Snowfall
In Julian, snow does not fall in June through October.Daylight
In September, the average length of the day is 12h and 22min.On the first day of September, sunrise is at 6:21 am and sunset at 7:10 pm. On the last day of the month, sunrise is at 6:40 am and sunset at 6:31 pm PDT.
Sunshine
The average sunshine in September is 10.4h.UV index
June through September, with an average maximum UV index of 6, are months with the highest UV index. A UV Index value of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for average individuals.Note: An average UV index of 6 in September transforms into this advice:
Apply measures and align with sun safety principles. Safeguarding against skin and eye injury is pivotal. The hours from 10 a.m. to 4 p.m. have the most intense UV radiation. As much as possible, limit direct sun exposure during this period. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in September?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
How many hours of daylight does Julian have in September?
When are sunrise and sunset in September?
How many hours of sunshine does Julian have in September?
When is the highest UV index?
How high is the UV index in September?
Average temperature in September
Julian, CA
- Average high temperature in September: 84.2°F
The warmest month (with the highest average high temperature) is August (87.3°F).
The month with the lowest average high temperature is December (61.3°F).
- Average low temperature in September: 62.8°F
The month with the highest average low temperature is August (64.9°F).
The coldest month (with the lowest average low temperature) is February (44.2°F).
Average pressure in September
Julian, CA
- Average pressure in September: 29.86"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Julian, CA
- Average wind speed in September: 4.1mph
The windiest month (with the highest average wind speed) is May (5.7mph).
The calmest month (with the lowest average wind speed) is September (4.1mph).
Average humidity in September
Julian, CA
- Average humidity in September: 53%
The month with the highest relative humidity is May (62%).
The month with the lowest relative humidity is November (51%).
Average rainfall in September
Julian, CA
- Average rainfall in September: 0.51"
The wettest month (with the highest rainfall) is February (0.94").
The driest month (with the least rainfall) is June (0.08").
Average rainfall days in September
Julian, CA
- Average rainfall days in September: 5.5 days
The month with the highest number of rainy days is March (7.6 days).
The month with the least rainy days is June (1.5 days).
Average snowfall in September
Julian, CA
- Average snowfall in September: 0"
The month with the highest snowfall is March (6.7").
The months with the least snowfall are June, July, August, September and October (0").
Average daylight in September /
Average sunshine in September
Julian, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in September: 10h and 2min
The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in September
Julian, CA
- Average sunshine days in September: 21.8 days
The month with the most sunshine days is June (27.5 days).
The month with the least sunshine days is July (19.4 days).
Average UV index in September
Julian, CA
- Average UV index in September: 6
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are November and December (UV index 3).
Average cloud cover in September
Julian, CA
- Average cloud cover in September: 8
The months with the most cloud cover are March and December (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 6).
Average visibility in September
Julian, 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).
Julian, California, USA
Weather forecast for your location
2. Allow the app to use your location