Ron with the 4Warn Weather Team said a Frost Advisory is in effect from midnight through 8 a.m. Tuesday for Sanilac, Genesee, Lapeer, and St. Clair counties. The freeze warning-level cold could drop temperatures to 32 degrees, so sensitive outdoor plants need protection before morning.
Sanilac Through St. Clair
The advisory covers four Southeast Michigan counties: Sanilac, Genesee, Lapeer, and St. Clair. Ron said frost is possible in parts of Southeast Michigan overnight, and the practical step for gardeners and homeowners is simple — cover plants or move them inside before temperatures fall.
That time window is the part that matters most. The advisory begins at midnight and runs through 8 a.m. Tuesday, which puts the coldest air in the same overnight stretch when the ground can cool fastest.
Metro Detroit Overnight
Metro Detroit will stay somewhat milder, with temperatures expected to fall to around 40 degrees. Colder locations farther north and west could slip into the 30s, so the advisory area is not uniform even though the warning covers the same overnight hours.
Skies are expected to be mostly clear tonight, and rain chances remain very limited through the period. That setup leaves the cold air in place long enough for frost to form where temperatures reach the threshold.
Tuesday To Monday
Tuesday should start chilly, then turn pleasant and dry as temperatures recover to around 65 degrees in the afternoon. After that, highs are expected to climb into the lower to mid-70s Wednesday, with west winds occasionally gusting above 20 mph and a couple of sprinkles possible Wednesday morning.
The rest of the week stays mild. Thursday is expected to be dry and mostly sunny with highs in the upper 60s, Friday near 68 degrees, and Saturday in the mid-60s before readings rise back into the lower 70s Sunday and Monday.
For anyone with sensitive outdoor plants, the frost threat is brief but immediate: protect them overnight, then expect a quick rebound once the sun is up and the cold air moves out.
