620
FXUS63 KGRB 100552
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1252 AM CDT Mon Aug 10 2026

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- Warmer today, with highs in the lower to middle 80s. Highs in
  the 80s through Wednesday, then slightly cooler late this week.

- Dry today, then potential for additional rounds of showers and
  storms late tonight through middle of the week. At this time,
  risk of severe storms is low.

&&

.DISCUSSION...
Issued at 1250 AM CDT Mon Aug 10 2026

Today into this evening...Scattered clouds and some fog (locally
dense) early will give way to mostly sunny skies in the afternoon
as we will be north of front that is moving through early this
morning. A couple CAMS hint that if some elevated showers form in
eastern SD this morning, they could drift over our southern areas
this afternoon. Something to watch, but most guidance keeps us
dry, so will ride with that idea. Dry weather and more sun than
Sunday will boost temps into the lower to middle 80s, though east
component winds will keep Lake Michigan shore/Door County cooler.
Dry weather holds for any evening activities, though patchy fog
may occur near Lake Michigan. Temperatures will be in the low to
mid 70s.

Shower and storm chances (15-30%) return late tonight through
Wednesday...Showers and storms developing this evening over
Dakotas forecast to produce shortwave/upper jet that shifts east
toward WI late tonight. Gradient of instability from MN to
southern WI, as is the stronger convergence with LLJ. Even so,
with the wave and elevated instability farther north, cannot rule
out some showers and storms on Tuesday morning, with perhaps
slight boost in coverage farther north during peak heating of
afternoon as MLCAPEs increase over 1000J/kg. Effective shear over
40 kts would support stronger storm if convection develops. SPC
does keep the marginal risk for severe farther south near the more
persistent frontal boundary/highest instability.

Rain chances (30-60%) then continue Tuesday night into Wednesday
as additional as another shortwave moves through the region and
the front remains close enough to our area. Similar to expectations
for late tonight and Tuesday, appears better signal for severe
remains south. However, late Tuesday night through Wednesday,
there is stronger forcing farther north and sufficient instability.
Seems like this time frame may hold the greatest chances for some
stronger storms over our area, especially if things slow a bit and
these factors catch up to at least the beginning of peak heating
on Wed. FWIW, ML progs show a weak "bump" in severe probs to 5-15%
for Wed after a relative minimum in severe potential Mon-Tue.

Dry and cooler late this week, then chances for rain (30-40%) return
for the weekend...High pressure builds in across the area Wednesday
night through Friday, pushing the front and lingering instability
south and generally keeping the area dry through the rest of the
week. Highs will settle into the 70s regionwide. Low temperatures
in the 40s north seem a certainty Thursday night with high overhead.
Low end from NBM (5th percentile) even points to potential for
upper 30s in typical cool spots near the U.P. border (e.g. KLNL).

The high eventually shifts east, allowing for the chance for showers
and thunderstorms to return to the area Friday night into next weekend.
On the early side, but does seem that Sunday would be the drier of the
two days.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1034 PM CDT Sun Aug 9 2026

Isolated showers and storms extended from west of Wausau to
Oconto, which is expected to end after 06z. A more extensive
cloud cover between five and ten thousand feet will slow the
arrival of the fog overnight. Thus did not go as low on the
visibilities at the TAF sites. A light northwest wind will back
to the south/southeast Monday afternoon, except around 18z for
KSUE and KMTW. Otherwise VFR conditions will prevail.

&&

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

&&

$$

DISCUSSION.....JLA
AVIATION.......Eckberg

NWS GRB Office Area Forecast Discussion