textproduct: Green Bay

KEY MESSAGES

- A few non-severe storms (30-60%) may impact mainly east- central into northeast Wisconsin late this afternoon/evening.

- There are intermittent 30-50% chances for storms Friday through early next week, but confidence in timing and potential severity are low at this time.

DISCUSSION

Issued at 1250 PM CDT Tue Aug 4 2026

A cold front will pass southeast across the area this evening into early Wednesday. Ahead of the front, the HREF surface-based CAPE reaches ~1000 J/kg across east-central Wisconsin, although synoptic forcing and deep layer shear are relatively modest. Isolated to scattered storms may develop ahead of the front, but the severe weather risk will be quite low. Additional showers may persist north of the surface boundary overnight into Wednesday.

A shortwave trough will drag a boundary south towards the area on Friday with a 20-40% chance of storms. Over the weekend into early next week, the local area will likely reside on the northern periphery of a seasonably warm, moist and unstable environment. Subtle shortwave troughs embedded in the seasonally strong mid-level westerly flow will interact with the low-level boundary and instability to produce rounds of showers and storms across the Midwest. However, predictability of storms at this range is low in this type of pattern. Some weather risk could evolve given the degree of flow aloft, but these trends will need to be evaluated in coming days as confidence increases with the degree of instability, timing of shortwaves, and boundary placement.

Otherwise, temperatures will trend seasonably warm late this week into the weekend. Some smoke aloft from wildfires may lead to hazy skies at times, but HRRR smoke model suggests low near surface smoke concentrations through Wednesday.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1250 PM CDT Tue Aug 4 2026

A cold front move southeast this afternoon and tonight with scattered thunderstorms most likely (40-60%) late this afternoon and evening across east-central Wisconsin. The greatest window for any storms was refined at KGRB, KATW and KMTW, but additional adjustments likely will be needed in subsequent updates. Showers may persist overnight into early Wednesday north of the front, but with the thunder threat lower. Southwest winds will shift west/northwest in the wake of the front or become light overnight. With the light flow, areas of IFR/MFR stratus may develop overnight into Wednesday morning.

GRB WATCHES/WARNINGS/ADVISORIES

WI...Beach Hazards Statement from 2 PM this afternoon to 10 PM CDT this evening for WIZ022-040-050. MARINE...Small Craft Advisory from 2 PM this afternoon to 10 PM CDT this evening for LMZ541>543.