September weather forecastEast Pasadena, CA
September
Weather in September
The first month of the autumn, September, is still a warm month in East Pasadena, California, with temperature in the range of an average high of 84.4°F (29.1°C) and an average low of 63.3°F (17.4°C).Temperature
Upon the beginning of September, East Pasadena's high-temperatures register at a warm 84.4°F (29.1°C), closely mirroring the preceding month. East Pasadena, during the nights of September, experiences an average temperature drop to a refreshing 63.3°F (17.4°C).Heat index
For most parts of September, the heat index is evaluated at a hot 86°F (30°C). If one continues to be active during enduring exposure, it could result in fatigue and heat cramps.Bear in mind that the heat index values are determined for shaded areas and light breezes. The direct sunshine could escalate the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is achieved by amalgamating air temperature with the relative humidity readings. One's perception of temperature is subjective, varying based on their activity and individual heat perception, influenced by factors like wind, clothing, and metabolic variations. Realize that direct exposure to sunlight can augment the felt heat, leading to a potential increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Children frequently do not understand the need for recuperation and hydration. Thirst, being a late manifestation of dehydration, underlines the need to hydrate frequently, especially when engaging in prolonged physical exercises.
Humidity
In September, the average relative humidity is 50%.Rainfall
In East Pasadena, in September, during 2.6 rainfall days, 0.16" (4mm) of precipitation is typically accumulated. Throughout the year, there are 50.1 rainfall days, and 8.5" (216mm) of precipitation is accumulated.Daylight
In September, the average length of the day is 12h and 22min.On the first day of September, sunrise is at 6:26 am and sunset at 7:17 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:37 pm PDT.
Sunshine
In East Pasadena, the average sunshine in September is 10.8h.UV index
June through September, with an average maximum UV index of 6, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum UV index, 6 during September, leads to the following recommendations:
Steer clear of overexposure. Fair-skinned individuals can be scorched in less than 20 minutes. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
East Pasadena, CA
- Average high temperature in September: 84.4°F
The warmest month (with the highest average high temperature) is August (87.1°F).
The month with the lowest average high temperature is December (61.7°F).
- Average low temperature in September: 63.3°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 (46.6°F).
Average pressure in September
East Pasadena, CA
- Average pressure in September: 29.89"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in September
East Pasadena, CA
- Average wind speed in September: 4.4mph
The windiest month (with the highest average wind speed) is April (5.8mph).
The calmest month (with the lowest average wind speed) is September (4.4mph).
Average humidity in September
East Pasadena, CA
- Average humidity in September: 50%
The month with the highest relative humidity is June (58%).
The month with the lowest relative humidity is November (47%).
Average rainfall in September
East Pasadena, CA
- Average rainfall in September: 0.16"
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
East Pasadena, CA
- Average rainfall days in September: 2.6 days
The month with the highest number of rainy days is March (7.8 days).
The month with the least rainy days is June (1.1 days).
Average daylight in September /
Average sunshine in September
East Pasadena, CA
- Average daylight in September: 12h and 24min
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 48min
The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The months with the least sunshine are January, February and December (Average sunshine: 6h and 54min).
Average sunshine days in September
East Pasadena, CA
- Average sunshine days in September: 25.2 days
The month with the most sunshine days is June (27.5 days).
The month with the least sunshine days is February (21.5 days).
Average UV index in September
East Pasadena, CA
- Average UV index in September: 6
The months with the highest UV index are June, July, August and September (UV index 6).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
East Pasadena, CA
- Average cloud cover in September: 6
The months with the most cloud cover are March and December (Cloud cover 21).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in September
East Pasadena, 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).
