No USGS gauge on Finn Creek reports water temperature, so this report is the hatch record and the classification rather than a live number.
No gauge on this river answered with a temperature when this page was built. That is a gap in the gauge network, not a judgement about the water.
Nothing in this region's hatch record peaks in September. The year-round insects — midges, scuds, sculpins — are still there, and they are what this month is fished on.
This is one river. The Minnesota report covers every region at once, and is refreshed at the same time as this page.