Summer concludes and the fall season begins across West Michigan. The autumnal equinox occurs at 5:05 AM on the 23rd marking the astronomical beginning of fall.
The typical high temperature cools from 78° on the 1st to 67° by the 30th. Low temperatures have the same trend. The low starts at 58° on the 1st and dips to 47° by the 30th. The September numbers are from the new thirty-year climate normals released by the National Climatic Data Center (NCDC). The National Weather Service in Grand Rapids began using the new normals on August 1, 2011.
Grand Rapids can see the first hint of winter during the month with a trace of snowfall recorded on several occasions.
September is the wettest month of the year; Grand Rapids typically picks up 4.28” of precipitation.
The amount of daylight available continues to dwindle, decreasing by 1 hour and 23 minutes in September. The percent of possible sunshine also decreases, down from 61% in August to 59% in September.
See the slideshow on the left side of the page for more September statistics.
Read more about the forecast for next month and the coming winter here: September 2011 outlook issued
There are many interesting weather events for September. Some involve end of summer severe thunderstorms, while others relate to intrusions of cool Canadian air and the first flakes of snow. I’ll highlight a few of the notable events from the National Weather Service Archives. To see the complete list, ‘Subscribe’ to the Grand Rapids Weather Examiner for a daily email of historical events.
9/1/1953 – A heat wave that began in late August continued into September, with record highs of 97 degrees at Grand Rapids and 96 at Lansing. The 95 degrees at Muskegon tied the record high for the month there.
9/3/1946 – There was an early taste of autumn as Grand Rapids falls to 32 degrees for their earliest freeze on record.
9/4/2008 – The remnants of Hurricane Gustav brought heavy rains to southern Lower Michigan. Muskegon sets a daily rainfall record of 3.25 inches and Grand Rapids sets a record with 2.82 inches.
9/10/1943 – The USS Grand Rapids is launched from Superior, Wisconsin. The weather in Grand Rapids, Michigan is cool with a low of 39 degrees. The ship was outfitted to take weather observations, but was damaged by a hurricane as it sailed towards Bermuda. It was repaired and provided vital weather observations in the North Atlantic through the end of World War Two.
9/12/1986 – From 6 to 12 inches of rain in three days resulted in record flooding from Muskegon to Saginaw. The flooding was worsened by the collapse of several dams. Ten people were killed and damage estimates approached half a billion dollars.
9/14/1928 – Tornadoes struck across Lower Michigan. A tornado hit in Mason County south of Scottville damaging at least three homes and injuring two people. The roof of one home was carried over a mile. Another tornado destroyed several barns, killing cattle about 2 miles south of Cedar Springs in Kent County. What may have been a tornado took part of the roof off a factory and warehouse in Grand Rapids.
9/16/1899 – Grand Rapids records a high of 98 degrees, setting the record for its hottest September temperature, which would be tied on September 2, 1913.
9/20/1957 – Thunderstorms with heavy rain of up to 2 inches flooded streets and viaducts in Grand Rapids.
9/22/1952 – Hail covered the ground like snow in Cascade Township, near Grand Rapids.
9/30/1899 – September ended on a very cool note with a record low of 21 degrees at Lansing and afternoon highs only in the 40s. The high of 44 degrees at Muskegon made for the coldest September maximum temperature on record there.