The National Weather Service has issued a frost advisory for much of the Northland for the overnight hours tonight, as temperatures may fall into the low to mid-30s across much of the region.
The advisory includes the Twin Ports away from Lake Superior; the Iron Range; interior parts of the Arrowhead; and much of Northwestern Wisconsin.
The Weather Service reports that low temperatures near the freezing mark forecast for the early morning hours Friday - between 2 and 8 a.m. - may damage sensitive plants left uncovered outside. Gardeners in the advisory area should take steps to protect fragile plants tonight.
The Duluth airport on average sees a frost by Sept. 23 and a hard freeze by Oct 18. Duluth's harbor doesn't see a first frost on average until Oct. 18 and escapes a hard freeze on average until Nov. 2.
Cook has Minnesota's earliest average first frost date, on Sept. 10, with an average hard freeze by Oct. 2.
