Average Weather in September in Indio California, United States
Daily high temperatures decrease by 8°F, from 104°F to 96°F, rarely falling below 88°F or exceeding 110°F.
Daily low temperatures decrease by 9°F, from 76°F to 67°F, rarely falling below 60°F or exceeding 83°F.
For reference, on July 12, the hottest day of the year, temperatures in Indio typically range from 79°F to 107°F, while on December 27, the coldest day of the year, they range from 42°F to 68°F.
Average High and Low Temperature in September
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on September. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in September
The month of September in Indio experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 11% throughout the month. The lowest chance of overcast or mostly cloudy conditions is 10% on September 18.
The clearest day of the month is September 18, with clear, mostly clear, or partly cloudy conditions 90% of the time.
For reference, on February 20, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 37%, while on September 18, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 90%.
Cloud Cover Categories in September
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Indio, the chance of a wet day over the course of September is essentially constant, remaining around 4% throughout.
For reference, the year's highest daily chance of a wet day is 14% on February 21, and its lowest chance is 1% on June 18.
Probability of Precipitation in September
The average sliding 31-day rainfall during September in Indio is essentially constant, remaining about 0.2 inches throughout, and rarely exceeding 0.8 inches or falling below -0.0 inches.
The lowest average 31-day accumulation is 0.2 inches on September 17.
Average Monthly Rainfall in September
Over the course of September in Indio, the length of the day is decreasing. From the start to the end of the month, the length of the day decreases by 1 hour, 0 minutes, implying an average daily decrease of 2 minutes, 3 seconds, and weekly decrease of 14 minutes, 24 seconds.
The shortest day of the month is September 30, with 11 hours, 51 minutes of daylight and the longest day is September 1, with 12 hours, 51 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month in Indio is 6:18 AM on September 1 and the latest sunrise is 20 minutes later at 6:38 AM on September 30.
The latest sunset is 7:09 PM on September 1 and the earliest sunset is 40 minutes earlier at 6:30 PM on September 30.
Daylight saving time is observed in Indio during 2021, but it neither starts nor ends during September, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:34 AM and sets 14 hours, 24 minutes later, at 7:58 PM, while on December 21, the shortest day of the year, it rises at 6:45 AM and sets 9 hours, 55 minutes later, at 4:40 PM.
Sunrise & Sunset with Twilight in September
The figure below presents a compact representation of key lunar data for September 2021. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases. The label associated with each bar indicates the date and time that the phase is obtained, and the companion time labels indicate the rise and set times of the Moon for the nearest time interval in which the moon is above the horizon.
Moon Rise, Set & Phases in September
The chance that a given day will be muggy in Indio is rapidly decreasing during September, falling from 17% to 3% over the course of the month.
For reference, on August 24, the muggiest day of the year, there are muggy conditions 20% of the time, while on November 14, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in September
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Indio is essentially constant during September, remaining within 0.1 miles per hour of 6.7 miles per hour throughout.
For reference, on May 3, the windiest day of the year, the daily average wind speed is 8.9 miles per hour, while on January 11, the calmest day of the year, the daily average wind speed is 6.5 miles per hour.
The lowest daily average wind speed during September is 6.6 miles per hour on September 5.
Average Wind Speed in September
The hourly average wind direction in Indio throughout September is predominantly from the west, with a peak proportion of 51% on September 3.
Wind Direction in September
The growing season in Indio typically lasts for 12 months (364 days), from around December 29 to around December 27, rarely starting after February 17, or ending before November 26.
The month of September in Indio is reliably fully within the growing season.
Time Spent in Various Temperature Bands and the Growing Season in September
The average accumulated growing degree days in Indio are very rapidly increasing during September, increasing by 907°F, from 5,623°F to 6,530°F, over the course of the month.
Growing Degree Days in September
The average daily incident shortwave solar energy in Indio is gradually decreasing during September, falling by 1.0 kWh, from 6.9 kWh to 6.0 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in September
For the purposes of this report, the geographical coordinates of Indio are 33.721 deg latitude, -116.217 deg longitude, and -10 ft elevation.
The topography within 2 miles of Indio is essentially flat, with a maximum elevation change of 75 feet and an average elevation above sea level of -7 feet. Within 10 miles is essentially flat (4,383 feet). Within 50 miles also contains extreme variations in elevation (11,719 feet).
The area within 2 miles of Indio is covered by shrubs (53%) and artificial surfaces (38%), within 10 miles by shrubs (67%) and cropland (24%), and within 50 miles by shrubs (74%) and bare soil (11%).
This report illustrates the typical weather in Indio, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 3 weather stations near enough to contribute to our estimation of the temperature and dew point in Indio.
For each station, the records are corrected for the elevation difference between that station and Indio according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Indio is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Indio and a given station.
The stations contributing to this reconstruction are: Thermal Airport (78%, 12 kilometers, southeast); Palm Springs International Airport (19%, 29 kilometers, northwest); and Twenty-Nine Palms, Marine Corps Air-Ground Combat Center (3.9%, 65 kilometers, north).
Time zones for airports and weather stations are provided by AskGeo.com .