September, on average, is a wet month. Average rainfall jumps from around three inches in August to nearly four inches in September. This increase can be attributed to the seasonal southward migration of the storm track out of central Canada closer to the northern tier of the United States. This month has held true to form, especially in northern portions. The NWS has received nearly four-and-quarter inches. Triple that total and you get the rainfall of September 1881??the wettest month on record.
On September 29th that year, ??The flood-gates of heaven were opened?? and almost 5.5 inches fell, the greatest one-day rainfall ever recorded in Marquette. A number of sidewalks in the city were undermined by the torrent, while many cellars flooded.
In Ishpeming, flash flooding occurred. Partridge Creek lost no time in flowing out of its banks ??and over everything else for blocks on either side of its course.?? Water kept rising all night, and by daylight, a large part of town was flooded. Alleys and backyards were covered with up to four feet of water, and in many cases people had to build bridges from their houses to the sidewalks. All area mines were flooded to some extent, with the Winthrop mine suffering the worst inundation. A creek running past it became blocked with floating debris, diverting its course into the mine. The deluge washed the soft ground from the foot-wall to the bottom of the open pit, filling the mine with 30 feet of water.
The local paper declared it the ??severest rainstorm?|within the memory of the oldest inhabitants.?? The downpour added to an already soggy month. September 1881 concluded with a total of 12.73 inches of rain in Marquette??the wettest month on record.
September 2012 will end dry and quiet. Right now, it appears that October will begin quiet, but things will likely get exciting as next week wears on. All medium-range forecast models predict a deep trough to develop in Canada by late next week (Image above). If this develops as forecast, it will bring us the coldest weather of this young season.