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 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
Montclair's shift from August to September is accompanied by an average high-temperature of a still hot 88.2°F (31.2°C), a slight deviation from 91°F (32.8°C). During September, Montclair notes a substantial drop from the daytime peak to an average minimum temperature of 63.5°F (17.5°C).Heat index
In September, the average heat index is calculated to be a tropical 89.6°F (32°C). One might feel worn out with persistent exposure and activity, resulting in heat cramps.Thinking about the heat index, one should account for its values in shaded areas with gentle breezes. In the presence of direct sunshine, the heat index could be augmented by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', is a measure that combines air temperature and relative humidity into a single value that indicates how hot the weather feels. The impact of temperature is individual, as people's perception of weather may change based on their body mass, height, and physical activity. In the direct sunlight, the weather's impact can be amplified, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are of high significance for children. Children often lack awareness of the importance of taking breaks and rehydrating. The feeling of thirst is a late indication of dehydration, so maintaining hydration, especially during long periods of physical activity, is critical.
Humidity
In Montclair, the average relative humidity in September is 44%.Rainfall
In Montclair, in September, it is raining for 2.5 days, with typically 0.12" (3mm) of accumulated precipitation. Throughout the year, there are 49.6 rainfall days, and 7.8" (198mm) of precipitation is accumulated.Snowfall
In Montclair, snow does not fall in January, March through December.Daylight
In Montclair, California, the average length of the day in September is 12h and 22min.On the first day of September, sunrise is at 6:24 am and sunset at 7:16 pm. On the last day of the month, sunrise is at 6:45 am and sunset at 6:35 pm PDT.
Sunshine
The average sunshine in September in Montclair is 10.7h.UV index
In September, the average daily maximum UV index is 6. A UV Index reading of 6 to 7 represents a high health hazard from exposure to the Sun's UV radiation for the average person.Note: In September, the UV index of 6 transforms into the following advice:
Ward off overexposure. Defence against solar harm is crucial. During the period from 10 a.m. to 4 p.m., UV radiation is highest. Try to avoid direct sunlight during these hours. Boost your sun resistance with garments that are densely woven yet spacious.
Frequently asked questions
Is it hot in Montclair during September?
What is the average humidity in September in Montclair?
How many days does it rain in September in Montclair?
When it does not snow in Montclair?
How many hours of daylight does Montclair have in September?
What time are sunrise and sunset in September in Montclair?
How many hours of sunshine does Montclair have in September?
What is the UV index intensity in September in Montclair?
Average temperature in September
Montclair, CA
- Average high temperature in September: 88.2°F
The warmest month (with the highest average high temperature) is August (91°F).
The month with the lowest average high temperature is December (62.1°F).
- Average low temperature in September: 63.5°F
The month with the highest average low temperature is August (65.8°F).
The coldest month (with the lowest average low temperature) is December (45.5°F).
Average pressure in September
Montclair, CA
- Average pressure in September: 29.88"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in September
Montclair, CA
- Average wind speed in September: 4.4mph
The windiest months (with the highest average wind speed) are April and May (5.8mph).
The calmest month (with the lowest average wind speed) is September (4.4mph).
Average humidity in September
Montclair, CA
- Average humidity in September: 44%
The months with the highest relative humidity are March and May (54%).
The month with the lowest relative humidity is August (42%).
Average rainfall in September
Montclair, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is February (1.77").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
Montclair, CA
- Average rainfall days in September: 2.5 days
The month with the highest number of rainy days is March (7.1 days).
The month with the least rainy days is June (1.2 days).
Average snowfall days in September
Montclair, CA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.1 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Montclair, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 10h and 4min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The months with the least sunshine are February and December (Average sunshine: 6h and 54min).
Average sunshine days in September
Montclair, CA
- Average sunshine days in September: 25.4 days
The month with the most sunshine days is June (28.2 days).
The month with the least sunshine days is February (21.5 days).
Average UV index in September
Montclair, CA
- Average UV index in September: 6
The months with the highest UV index are July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
Montclair, CA
- Average cloud cover in September: 6
The month with the most cloud cover is December (Cloud cover 21).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in September
Montclair, 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).
Montclair, California, USA
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