Weather service issues frost advisory for northwest, northern and central Wisconsin, but assures us 'summer will return'

The National Weather Service issued an overnight frost advisory Sunday for much of northern Wisconsin but said the cold spell will be brief.

The frost advisory covers "a good chunk" of the northwest and northern part of the state and will stretch down into Marquette, Green Lake, Sauk and Columbia counties, said Rebecca Hansen, meteorologist for the NWS in Sullivan. The advisory is in effect from about 1 to 8 a.m. Monday.

In those areas, temperatures are expected to drop into the low to mid-30s, she said. Near the border of Wisconsin and the Upper Peninsula of Michigan, temperatures could dip below 30.  

In the Milwaukee area, temperatures are expected to be around 40, slightly higher in the city and slightly lower inland toward Waukesha and West Bend, according to Hansen. 

"Temperatures could be a little bit cooler in the river valleys and the low-lying areas," she said. Those areas could experience "patchy frost." 

Hansen recommended bringing sensitive plants indoors if possible or covering them with a tarp, blanket or sheet. Watering the plants prior to nightfall could help keep them warmer longer as well, she said. 

"Generally, it doesn't look like we're going to see temperatures that cool again over the next week," Hansen said. "We should potentially really warm up into Memorial Day weekend. Summer will return." 

On Monday, most of the state will warm into the low 60s, and 50s closer to the lake, she said.

Contact Hannah Kirby at hannah.kirby@jrn.com. Follow her on Twitter at @HannahHopeKirby.