NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 061854
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
154 PM CDT Mon Jul 6 2026

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Shower and storm chance (30-50%) expected across the Northwoods
  Tuesday afternoon.

- Better chance (60-85%) for showers and storms expected
  Wednesday, spreading across the whole area. A few storms may
  become strong or severe.

- Temperatures rising slightly above normal for the start of the
  work week. Humidity levels also slightly increase midweek.

&&

.DISCUSSION...
Issued at 154 PM CDT Mon Jul 6 2026

Quiet conditions remain in the area today and tonight. High
pressure lingers on across the region today making for a sunny
afternoon with weak winds.

Rain Tuesday...
A fast moving shortwave will help develop rain and showers
upstream late tonight and then sustain them into portions of
central Wisconsin. Most guidance does keep a few showers around
into Wisconsin but also holds on to a weakening trend, so
maintained some low end (~20% chance) for a stray shower or two
near the Upper Peninsula border Tuesday morning. Additional rain
potential will follow during the afternoon to early evening hours
as a slow moving frontal boundary drops southeastwards across far
northern Wisconsin and the Upper Peninsula. With limited
instability and upper support, would expect some rumbles of
thunder but no severe weather for Tuesday. Additionally, with the
front still largely to the north, areas in east-central including
the Fox Valley and Green Bay areas should remain dry through the
daytime.

Tuesday night through Thursday... the frontal boundary will then
slowly progress southeastwards overnight through Wednesday,
expanding the rain and storms over the region. Most guidance
suggests two rounds of active weather for the daytime Wednesday,
with some showers and storms crossing the region early Wednesday,
a brief break sometime in the afternoon, and then the second round
through the area again. The exact timing of each round remains
uncertain at this time unfortunately, as the exact timing of the
frontal passage remains uncertain. Heavy rainfall will be the main
concern for the period, due to a combination of the ample
moisture available and the multiple rounds possible over the same
region. The highest potential will be across north-central
Wisconsin where guidance keeps around 50-70% chance of over an
inch of rainfall, tapering quickly southwards. Given the amount of
moisture and the potential for convection, would expect some
localized higher totals pushing closer to two or more inches to be
possible over some areas in northern Wisconsin. Severe potential
appears to be largely limited to any development in the late
afternoon to early evening hours. Earlier rounds of precipitation
may hamper the amount of instability available for the afternoon,
so this will be a key to watch, but bulk shear around 35 knots may
suffice to organize a few storms. The most likely severe threat
at this time is expected to be winds. Soundings are fairly warm
but do have some CAPE through the hail growth zone so some hail
will also be possible at times. Behind this, the slow moving
front will continue to work its way through the region overnight
into Thursday morning, possibly bringing some additional rain and
thunder into the region. By this point, drier conditions should
return to the northwoods, shifting the heavier rainfall potential
southwards to central and eas-central Wisconsin.

Rest of the forecast...
Behind the active weather in the middle of the week guidance
generally brings back high pressure, which should keep widespread
precipitation away from our area. However, there are some early
hints that the forecast may not remain completely dry as a couple
weak shortwave could produce a few stray showers or storms in the
afternoon over the weekend.

Temperatures...
High temperatures are expected to be above normal the next couple
of days, getting into the middle to upper 80s Tuesday and possibly
again on Wednesday, although this may be hampered by active
weather. Once the front rolls through, high temperatures will drop
towards the upper 70s to lower 80s before warming again towards
the upper 80s over the weekend.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1214 PM CDT Mon Jul 6 2026

VFR conditions are expected to prevail through the TAF period.
Sunny skies may see some brief high clouds and fair weather cu at
times during the afternoon but no impacts to aviation are
expected. A few showers may work their way into far northwestern
Wisconsin Tuesday morning, but are not expected to get as far as
RHI, so these were excluded in the current TAF period.

Winds will largely remain light across the region today, remaining
fairly light and variable. The only exception will be for MTW,
where winds could be a little more breezy off of Lake Michigan.

&&

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

&&

$$

DISCUSSION.....Uhlmann
AVIATION.......Uhlmann