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 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
September marks a gentle change in average high-temperature, declining from August's extremely hot 106.5°F (41.4°C) to a torrid 99.9°F (37.7°C). Throughout September, the nighttime temperature in Holtville averages to a warm 80.1°F (26.7°C).Humidity
In Holtville, California, the average relative humidity in September is 26%.Rainfall
In Holtville, California, in September, it is raining for 4.2 days, with typically 0.39" (10mm) of accumulated precipitation. In Holtville, during the entire year, the rain falls for 29.5 days and collects up to 2.99" (76mm) of precipitation.Daylight
The average length of the day in September is 12h and 22min.On the first day of the month, sunrise is at 6:16 am and sunset at 7:05 pm. On the last day of September, sunrise is at 6:35 am and sunset at 6:26 pm PDT.
Sunshine
In Holtville, the average sunshine in September is 10.2h.UV index
The average daily maximum UV index in September is 8. A UV Index reading of 8 to 10 represents a very high health hazard from unsafe exposure to UV radiation for the average person.Note: In September, a daily UV index of 8 turns into the following recommendations:
Take extra precautions. Fair-skinned individuals may get burned in less than 10 minutes. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is it in Holtville in September?
What is the average humidity in September in Holtville?
How many days does it rain in September in Holtville?
What is the average length of the day in September in Holtville?
What time are sunrise and sunset in September in Holtville?
How long on average sun shines in September in Holtville?
What is the UV index intensity in September in Holtville?
Average temperature in September
Holtville, CA
- Average high temperature in September: 99.9°F
The warmest month (with the highest average high temperature) is July (107.2°F).
The month with the lowest average high temperature is December (67.3°F).
- Average low temperature in September: 80.1°F
The month with the highest average low temperature is August (85.6°F).
The coldest month (with the lowest average low temperature) is January (50°F).
Average pressure in September
Holtville, CA
- Average pressure in September: 29.81"Hg
The month with the highest atmospheric pressure is January (30.08"Hg).
The month with the lowest atmospheric pressure is June (29.77"Hg).
Average wind speed in September
Holtville, CA
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is April (7.7mph).
The calmest months (with the lowest average wind speed) are January and August (5.5mph).
Average humidity in September
Holtville, CA
- Average humidity in September: 26%
The month with the highest relative humidity is December (39%).
The month with the lowest relative humidity is June (21%).
Average rainfall in September
Holtville, CA
- Average rainfall in September: 0.39"
The wettest month (with the highest rainfall) is July (0.55").
The driest month (with the least rainfall) is May (0.04").
Average rainfall days in September
Holtville, CA
- Average rainfall days in September: 4.2 days
The month with the highest number of rainy days is July (6.3 days).
The month with the least rainy days is May (0.9 days).
Average daylight in September /
Average sunshine in September
Holtville, 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 1min
The month with the most sunshine is June (Average sunshine: 12h and 12min).
The month with the least sunshine is December (Average sunshine: 7h and 6min).
Average sunshine days in September
Holtville, CA
- Average sunshine days in September: 24.4 days
The month with the most sunshine days is May (29.9 days).
The month with the least sunshine days is July (21.8 days).
Average UV index in September
Holtville, CA
- Average UV index in September: 8
The months with the highest UV index are July and August (UV index 9).
The month with the lowest UV index is December (UV index 4).
Average cloud cover in September
Holtville, CA
- Average cloud cover in September: 7
The month with the most cloud cover is December (Cloud cover 17).
The month with the least cloud cover is June (Cloud cover 5).
Average visibility in September
Holtville, 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).
Holtville, California, USA
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