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
With the transition into September, Herald notes an average high-temperature of a still tropical 88.5°F (31.4°C), closely resembling August. Herald demonstrates a significant disparity from daytime highs throughout the month of September, with an average nighttime temperature of 58.6°F (14.8°C).Heat index
The heat index value during September is estimated at a tropical 89.6°F (32°C). Enduring exposure and unrelenting activity might cause a state of weariness, potentially leading to heat cramps.From a standpoint of the heat index, values pertain to shaded conditions and mild breezes. The heat index values could be amplified by up to 15 Fahrenheit (8 Celsius) degrees in direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', ties air temperature with relative humidity to produce the perceived temperature sensation. This effect is subjective, differing among individuals based on their physical activity and perception of heat, which can be influenced by factors like wind, clothing, and metabolic variances. When in direct sunlight, one should be cautious as it can raise the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially vital to children. Young ones generally face higher dangers than adults since they sweat less. Along with their large skin surface area compared totheir small bodies and increased heat production from their activities, the risks are heightened.
Humidity
The average relative humidity in September is 46%.Rainfall
In Herald, in September, it is raining for 1.5 days, with typically 0.08" (2mm) of accumulated precipitation. Throughout the year, there are 63.8 rainfall days, and 12.6" (320mm) of precipitation is accumulated.Snowfall
January through November are months without snowfall.Daylight
In Herald, the average length of the day in September is 12h and 25min.On the first day of the month, sunrise is at 6:35 am and sunset at 7:34 pm. On the last day of September, in Herald, sunrise is at 7:00 am and sunset at 6:48 pm PDT.
Sunshine
In September, the average sunshine in Herald, California, is 11.3h.UV index
In Herald, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: An average UV index of 5 in September transforms into this advice:
Preventative actions are necessary - The mandate to avoid skin and eye damage is in place. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage.
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 Herald have in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Herald, CA
- Average high temperature in September: 88.5°F
The warmest month (with the highest average high temperature) is July (93.9°F).
The month with the lowest average high temperature is December (55°F).
- Average low temperature in September: 58.6°F
The month with the highest average low temperature is August (58.8°F).
The coldest month (with the lowest average low temperature) is December (41°F).
Average pressure in September
Herald, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Herald, CA
- Average wind speed in September: 4.6mph
The windiest months (with the highest average wind speed) are February and June (5.8mph).
The calmest month (with the lowest average wind speed) is November (4.4mph).
Average humidity in September
Herald, CA
- Average humidity in September: 46%
The month with the highest relative humidity is March (75%).
The month with the lowest relative humidity is July (45%).
Average rainfall in September
Herald, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is February (2.4").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in September
Herald, CA
- Average rainfall days in September: 1.5 days
The month with the highest number of rainy days is March (12.4 days).
The month with the least rainy days is June (0.9 days).
Average snowfall days in September
Herald, CA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (0.1 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Herald, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 11h and 2min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 54min).
Average sunshine days in September
Herald, CA
- Average sunshine days in September: 27.5 days
The month with the most sunshine days is August (29.3 days).
The month with the least sunshine days is March (17.8 days).
Average UV index in September
Herald, CA
- Average UV index in September: 5
The month with the highest UV index is June (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in September
Herald, CA
- Average cloud cover in September: 7
The month with the most cloud cover is March (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in September
Herald, 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).
Herald, California, USA
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