Average Weather in September in Brainerd Minnesota, United States
Daily high temperatures decrease by 12°F, from 75°F to 63°F, rarely falling below 51°F or exceeding 85°F.
Daily low temperatures decrease by 11°F, from 55°F to 43°F, rarely falling below 31°F or exceeding 65°F.
For reference, on July 18, the hottest day of the year, temperatures in Brainerd typically range from 60°F to 82°F, while on January 15, the coldest day of the year, they range from 3°F to 21°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 Brainerd experiences increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 33% to 42%.
The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 67% of the time.
For reference, on February 5, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 63%, while on July 31, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 73%.
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 Brainerd, the chance of a wet day over the course of September is rapidly decreasing, starting the month at 31% and ending it at 25%.
For reference, the year's highest daily chance of a wet day is 41% on June 29, and its lowest chance is 6% on February 4.
Probability of Precipitation in September
The average sliding 31-day rainfall during September in Brainerd is gradually decreasing, starting the month at 2.8 inches, when it rarely exceeds 4.8 inches or falls below 1.2 inches, and ending the month at 2.4 inches, when it rarely exceeds 4.4 inches or falls below 0.7 inches.
Average Monthly Rainfall in September
Over the course of September in Brainerd, 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, 34 minutes, implying an average daily decrease of 3 minutes, 14 seconds, and weekly decrease of 22 minutes, 40 seconds.
The shortest day of the month is September 30, with 11 hours, 44 minutes of daylight and the longest day is September 1, with 13 hours, 18 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month in Brainerd is 6:37 AM on September 1 and the latest sunrise is 37 minutes later at 7:14 AM on September 30.
The latest sunset is 7:55 PM on September 1 and the earliest sunset is 57 minutes earlier at 6:58 PM on September 30.
Daylight saving time is observed in Brainerd during 2018, 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 5:24 AM and sets 15 hours, 48 minutes later, at 9:12 PM, while on December 21, the shortest day of the year, it rises at 7:57 AM and sets 8 hours, 36 minutes later, at 4:32 PM.
Sunrise & Sunset with Twilight in September
The chance that a given day will be muggy in Brainerd is rapidly decreasing during September, falling from 12% to 1% over the course of the month.
For reference, on July 20, the muggiest day of the year, there are muggy conditions 24% of the time, while on October 27, 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 Brainerd is increasing during September, increasing from 10.6 miles per hour to 11.6 miles per hour over the course of the month.
For reference, on April 2, the windiest day of the year, the daily average wind speed is 12.7 miles per hour, while on August 1, the calmest day of the year, the daily average wind speed is 9.3 miles per hour.
Average Wind Speed in September
Wind Direction in September
The growing season in Brainerd typically lasts for 4.7 months (143 days), from around May 8 to around September 28, rarely starting before April 18 or after May 27, and rarely ending before September 11 or after October 14.
During September in Brainerd, the chance that a given day is within the growing season is very rapidly decreasing falling from 99% to 43% over the course of the month.
Time Spent in Various Temperature Bands and the Growing Season in September
The average accumulated growing degree days in Brainerd are increasing during September, increasing by 286°F, from 1,967°F to 2,254°F, over the course of the month.
Growing Degree Days in September
The average daily incident shortwave solar energy in Brainerd is rapidly decreasing during September, falling by 1.5 kWh, from 5.3 kWh to 3.8 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 Brainerd are 46.358 deg latitude, -94.201 deg longitude, and 1,207 ft elevation.
The topography within 2 miles of Brainerd contains only modest variations in elevation, with a maximum elevation change of 108 feet and an average elevation above sea level of 1,200 feet. Within 10 miles also contains only modest variations in elevation (187 feet). Within 50 miles contains only modest variations in elevation (633 feet).
The area within 2 miles of Brainerd is covered by artificial surfaces (46%), trees (35%), and cropland (10%), within 10 miles by trees (63%) and water (15%), and within 50 miles by trees (56%) and cropland (32%).
This report illustrates the typical weather in Brainerd 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 Brainerd.
For each station, the records are corrected for the elevation difference between that station and Brainerd 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 Brainerd is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Brainerd and a given station.
The stations contributing to this reconstruction are: Brainerd Lakes Regional Airport (89%, 7 kilometers, northeast); Staples Municipal Airport (6%, 47 kilometers, west); and Little Falls, Little Falls/Morrison County Airport-Lindbergh Field (6%, 47 kilometers, south).
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Time zones for aiports and weather stations are provided by AskGeo.com .