Average Weather in September in Merced California, United States
In Merced, the month of September is characterized by falling daily high temperatures, with daily highs decreasing by 8°F, from 93°F to 85°F over the course of the month, and rarely exceeding 100°F or dropping below 75°F.
Daily low temperatures decrease by 5°F, from 61°F to 56°F, rarely falling below 50°F or exceeding 67°F.
For reference, on July 18, the hottest day of the year, temperatures in Merced typically range from 64°F to 96°F, while on December 30, the coldest day of the year, they range from 38°F to 53°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 Merced experiences gradually increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 10% to 16%.
The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 90% of the time.
For reference, on February 8, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 51%, while on August 8, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 92%.
Cloud Cover in September
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Merced, the chance of a wet day over the course of September is gradually increasing, starting the month at 1% and ending it at 5%.
For reference, the year's highest daily chance of a wet day is 28% on February 21, and its lowest chance is 0% on August 2.
Probability of Precipitation in September
The average sliding 31-day rainfall during September in Merced is gradually increasing, starting the month at 0.1 inches, when it rarely exceeds 0.2 inches or falls below -0.0 inches, and ending the month at 0.4 inches, when it rarely exceeds 1.2 inches or falls below -0.0 inches.
Average Monthly Rainfall in September
Over the course of September in Merced, the length of the day is rapidly decreasing. From the start to the end of the month, the length of the day decreases by 1 hour, 8 minutes, implying an average daily decrease of 2 minutes, 21 seconds, and weekly decrease of 16 minutes, 27 seconds.
The shortest day of the month is September 30, with 11 hours, 49 minutes of daylight and the longest day is September 1, with 12 hours, 57 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month in Merced is 6:32 AM on September 1 and the latest sunrise is 24 minutes later at 6:56 AM on September 30.
The latest sunset is 7:30 PM on September 1 and the earliest sunset is 44 minutes earlier at 6:46 PM on September 30.
Daylight saving time is observed in Merced during 2017, 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 5:41 AM and sets 14 hours, 44 minutes later, at 8:25 PM, while on December 21, the shortest day of the year, it rises at 7:12 AM and sets 9 hours, 35 minutes later, at 4:48 PM.
Sunrise & Sunset with Twilight in September
The chance that a given day will be muggy in Merced is essentially constant during September, remaining around 0% throughout.
For reference, on July 20, the muggiest day of the year, there are muggy conditions 1% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in September
The average hourly wind speed in Merced is essentially constant during September, remaining within 0.2 miles per hour of 3.3 miles per hour throughout.
For reference, on June 6, the windiest day of the year, the daily average wind speed is 4.5 miles per hour, while on November 2, the calmest day of the year, the daily average wind speed is 2.8 miles per hour.
Average Wind Speed in September
Wind Direction in September
The average daily incident shortwave solar energy in Merced is decreasing during September, falling by 1.5 kWh, from 6.9 kWh to 5.4 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 Merced are 37.302 deg latitude, -120.483 deg longitude, and 167 ft elevation.
The topography within 2 miles of Merced is essentially flat, with a maximum elevation change of 46 feet and an average elevation above sea level of 167 feet. Within 10 miles is essentially flat (466 feet). Within 50 miles contains only modest variations in elevation (6,939 feet).
The area within 2 miles of Merced is covered by artificial surfaces (84%) and cropland (16%), within 10 miles by cropland (66%) and grassland (24%), and within 50 miles by cropland (42%) and grassland (36%).
This report illustrates the typical weather in Merced year round, 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 Merced.
For each station, the records are corrected for the elevation difference between that station and Merced 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 Merced is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Merced and a given station.
The stations contributing to this reconstruction are: Merced Municipal Airport (86%, 3.3 kilometers, southwest); Castle Airport (13%, 12 kilometers, northwest); and Madera Municipal Airport (1.5%, 48 kilometers, southeast).
Time zones for aiports and weather stations are provided by AskGeo.com .