NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 310341
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1041 PM CDT Thu Jul 30 2026

Updated aviation portion for 06Z TAF issuance

.KEY MESSAGES...

- Chance (30 to 50%) for showers or storms today, mainly north of
  Highway 29. No strong storms are expected.

- Wildfire smoke may reach the surface at times today and tonight.
  A drop to moderate (yellow category) air quality is expected.

- Greater chances (50 to 70%) for showers and storms return
  Friday into Friday night. No severe weather is expected.

&&

.DISCUSSION...
Issued at 1035 AM CDT Thu Jul 30 2026

Rain/storm chances... CAMs are still showing a signal for
diurnal showers/storms percolating over the north this afternoon
into this evening where modest instability (1,000 to 1,500 J/kg)
builds. Agitated cu has already begun popping as of early this
afternoon, though remain unsure whether or not elevated smoke will
hinder further shower development. Regardless, no strong or
severe storms are expected, with most areas especially south of
Hwy 29 remaining dry with ridging overhead.

Next chances for more widespread rain/thunder arrive Friday
morning, continuing into Saturday. Remain pessimistic about
excessive rainfall potential given a more southerly solution
presented by 12Z suite of model runs, with higher PWATs (1.75"+)
holed up closer to the surface low. Additionally, dry air from
departing high pressure persists to around 10k ft through Friday
afternoon, delaying top down saturation of the profile. NBM
continues to show broadbrush 40 to 60% chances for receiving 0.5"
of QPF confined along/south of the Hwy 10 corridor, which doesn't
lend confidence to a forecast of widespread soaking rainfall.
Convective activity should remain minimal due to weak shear (< 20
knots) and limited forcing. Overall, signs point toward a period
of light to moderate stratiform rain Friday and Friday night.

Expect light rain to persist through Saturday morning as the cold
front continues to sag south. Dry weather should then settle in
through around the mid-week timeframe as high pressure and upper
ridging build.

Smoke... Expect air quality readings in the moderate (yellow)
category today into Friday as subsidence from high pressure brings
an elevated smoke plume near the surface. Per upstream obs, little
to no deterioration in visibility are expected. Overall air
quality impacts are not expected to be as drastic as earlier in
the month.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1041 PM CDT Thu Jul 30 2026

VFR conditions are expected tonight. BKN to SCT cigs based around
8kft will linger over much of the region, with light and variable
winds overnight.

Friday a surface low passing across the middle Mississippi Valley
will bring another round of rain to the region. Rain is progged to
arrive from west to east during the early afternoon. With limited
instability have left TSRA out of all TAF sites with this issuance.
Rain should be falling from a mid level cloud deck, based 7-10 kft
AGL. Cigs across central WI may lower near MVFR Friday evening. Main
ovation will likely be periods of MVFR vsbys as any heavier showers
pass over an terminals.

Light winds 5-10 kts are expected to back from the southwest to
northeast Friday.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION.....Goodin
AVIATION.......GK