Green Bay, WI Weather

Key Messages

- Staying mild into the weekend, with high temperatures inland of Lake Michigan warming into the mid 60s to low 70s.

- Rain chances (30 to 50%) Saturday night over northern Wisconsin, and late Monday into Tuesday mainly over central Wisconsin.

- Cooler start to next week, with highs mainly in the 50s.

Discussion

Issued at 1200 PM CDT Fri Oct 23 2026

Fog... Similar to yesterday, fog bank has been slow to lift along the lakeshore through the late morning and early afternoon as onshore flow persists. However, most inland areas are now seeing mainly low stratus as mixing increases. Dense fog regime looks to come to an end tonight as southerly flow increases out ahead of an approaching cold front, though could still see some patchy dense fog along the lakeshore into Saturday morning. However, would venture to say that widespread advisory level fog does not appear likely.

Rain chances... Majority of the next week will be characterized by periodic light rain chances as several transient shortwaves and weak frontal boundaries migrate through the area. First round will be Saturday into Sunday as moisture return along a slow-moving boundary nudges PWATs into the 1 to 1.25" range (~95th percentile). Upper jet energy working in tandem with front in the vicinity should then keep on and off rain chances in the forecast through at least the middle of next week. However, overall rainfall amounts should be held to a minimum with high pressure in the area and lack of stronger forcing at the surface. Would venture to say that most areas will see less than half an inch of QPF throughout the entire forecast period.

Temperatures... Arctic high sliding south in the wake of the front Monday into Tuesday will bring about a spell of below average temperatures during the middle of next week, with highs only getting into the mid 40s to mid 50s. However, cooler temperatures will be short-lived as return flow sets up on Wednesday, warming highs back up into the 50s and 60s. Monday night lows will fall into the low to mid 30s across the north, though little to no impacts are expected since the growing season has come to an end. Looking ahead, slightly above normal temperatures are favored toward the end of the month and into November as upper flow flattens out, though there is still uncertainty this far out as shown in ensemble spread.

Aviation

for 00Z TAF Issuance Issued at 704 PM CDT Fri Oct 23 2026

While not as dense or widespread as previous nights, low clouds and fog will again develop/expand across eastern WI this evening into tonight, mainly impacting MTW with LIFR conditions (briefly lower possible overnight). The clouds/fog could expand far enough west and impact GRB for a time later tonight. Otherwise, VFR conditions are expected as mid and high clouds spread across the region through the TAF period.

Southeast to south surface winds will remain under 10 kts tonight. As winds at 2000 ft increase overnight, LLWS will develop across central and north-central WI, impacting RHI, CWA and AUW. South winds will increase Saturday morning, with gusts to around 20 kts expected from mid-morning into the mid-afternoon.

Grb Watches

None.