LA CROSSE, Wis. – A crisp, quiet chill is sweeping across the upper Mississippi Valley this week, setting up the first widespread frost of the season. The air feels sharper this morning — calm, dry, and primed for a deep fall cooldown that will dip below freezing before dawn Thursday.
According to the National Weather Service in La Crosse, a Frost Advisory is in effect from 2 a.m. to 9 a.m. Thursday for much of western Wisconsin, northeast Iowa, and southeast Minnesota. Lows will fall into the upper 20s and lower 30s, cold enough to end the growing season across rural valleys and river flats. Areas west of the Mississippi River, including Winona, Decorah, and Rochester, are also likely to experience hard frost and isolated freeze pockets by sunrise Friday.
Residents should take precautions now: cover tender plants, store garden hoses, and protect exposed outdoor faucets. Drivers may need a few extra minutes Thursday morning to clear frosted windshields. The sharp temperature drop will also make bridges and rural roads slick where moisture lingers.
Sunshine will return quickly Thursday, with light northwest winds and highs near the low 50s. By Friday, frost will again form before daybreak as the calm, dry air lingers. The weekend turns milder and bright, a welcome stretch for outdoor cleanup or early Halloween setup, with highs climbing near 60°F Saturday.
To be fair, no snow is expected yet — but this frost marks Wisconsin’s shift into late-fall mode. Across the Midwest, cold air is building, and folks from La Crosse to Eau Claire are watching for that first whisper of winter in the forecast maps.
Five-Day Forecast for La Crosse, WI:
Wed: 49/32 – Cloudy early; clearing late with light breeze.
Thu: 52/29 – Widespread frost early; sunny and cool.
Fri: 56/35 – Frost early; bright and calm.
Sat: 60/45 – Mostly sunny; pleasant fall day.
Sun: 62/46 – Partly cloudy; mild afternoon.
