Green Bay, Wis. – A biting chill clung to the air across eastern Wisconsin early Thursday, the kind that quiets the fields and sends a shimmer of frost across windshields before sunrise. By Friday morning, that chill turns serious as a Freeze Warning goes into effect for much of northeast Wisconsin — a clear signal that fall’s final act has begun.
According to the National Weather Service in Green Bay, temperatures between 30°F and 34°F are expected from 2 a.m. to 9 a.m. Friday. The warning includes Brown, Outagamie, Kewaunee, Manitowoc, Calumet, and Winnebago counties, covering communities such as Green Bay, Appleton, Neenah, and Manitowoc. Frost and freeze conditions could damage sensitive vegetation and unprotected plumbing. Residents are urged to cover garden plants, wrap faucets, and disconnect hoses before dusk.
Thursday brings a cloudy start with a chance for light sprinkles before skies clear late in the day. Temperatures will hover near 50°F, then drop quickly after sunset. Calm air overnight will allow cold pockets to form in low-lying areas — especially along rural stretches of I-41 and Highway 29 — where frost will thicken fastest.
Friday will feel brisk but bright, with highs near 51°F under sunny skies. The air will stay cool through Saturday morning before modest warming lifts highs into the mid-50s. Early next week, a milder breeze returns from the southwest, though long-range models hint at colder air pooling over the Great Lakes by late October. Some forecasters even eye the first flake potential in far northern Wisconsin near the Upper Peninsula by month’s end — a reminder that true winter isn’t far behind.
Five-Day Forecast for Green Bay, WI:
Thu: 50/33 – Cloudy early, clearing late; patchy frost forming.
Fri: 51/31 – Hard freeze early; bright, cool afternoon.
Sat: 56/33 – Mostly sunny; crisp, calm day.
Sun: 58/44 – Partly sunny; mild late-fall feel.
Mon: 56/44 – Increasing clouds; light rain chance late.
