580
FXUS63 KGRB 142305
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
605 PM CDT Sun Jun 14 2026

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- 60-90% chance of showers and storms, especially Tuesday
  afternoon and again Wednesday afternoon and evening. The risk
  of severe weather is low.

- 30-50% chance of showers and storms on Thursday

- Below normal temperatures are expected through much of the work
  week.

&&

.DISCUSSION...
Issued at 246 PM CDT Sun Jun 14 2026

A 500mb closed low near Hudson Bay is going to meander over the
next several days, resulting in a cool west-northwest flow pattern
that will bring periodic chances of showers and storms. The cool
air aloft, combined with daytime heating could trigger isolated to
scattered showers and storms (30-50% chance) across the north
Monday afternoon. Meanwhile, the first upper level disturbance
across the Dakotas will swing southeast to the Minnesota/Wisconsin
border by 12z Tuesday. This feature will move across Wisconsin
during the day Tuesday, bringing a 60-90% chance of showers and
some storms. The risk of severe weather is low, although could not
rule out some small hail with stronger storms. Showers and storms
will come to an end Tuesday afternoon or early evening.

Attention turns to the next upstream disturbance across the
northern plains at 12z Wednesday. This feature has better dynamics
with it, thus could not rule out a stronger storm. Rain chances
will increase to 60-90% Wednesday afternoon into Wednesday
evening. There will be a break in the rain later Wednesday night,
however the cool cyclonic flow aloft and daytime heating will
result in isolated to scattered showers and storms redeveloping
later Thursday morning and afternoon. Dry conditions are expected
Friday with the next chance of showers and storms over next
weekend.

Below normal temperatures are expected through the week, with some
of the coolest temperatures on Monday and Tuesday where highs in
some spots may not get out of the low to middle 60s.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 605 PM CDT Sun Jun 14 2026

VFR conditions are expected to prevail through the TAF period across
the forecast area.

The arrival of a much drier air mass has lead to a quick decrease in
stratocumulus clouds this afternoon. Skies are expected to become
clear across the region tonight. A scattered fair weather cu field
is expected to develop Monday morning based around 3.5-4 kft
initially, but rising through the day. There is a chance for a round
of scattered showers and isolated thunderstorms, mainly across
northern WI Monday afternoon and evening. Have framed out the best
timing for showers at RHI with a PROB30 group for now.

West winds are not expected to be as gusty Monday, however, gusts up
to 20kts will be possible again beginning after 14-16Z.

&&

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

&&

$$

DISCUSSION.....Eckberg
AVIATION.......GK

NWS GRB Office Area Forecast Discussion