NWS-Green Bay Forecast Discussion

 

						FXUS63 KGRB 220557
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1257 AM CDT Wed Apr 22 2026

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Dry weather is forecast through Thursday, which will continue
  the gradual drop on area rivers.

- Temperatures will be well above normal through Friday, with
  highs in the 70s to around 80 degrees on Thursday.

- Showers and thunderstorms are expected Thursday night into
  Friday. Heavy rainfall may accompany any thunderstorms, with a
  20-40% chance of exceeding an inch of rain.

- Another round of showers and thunderstorms is expected Monday
  and Tuesday. Heavy rainfall is also expected with this system,
  with a 30-50% chance of exceeding an inch of rain.

&&

.DISCUSSION...
Issued at 1257 AM CDT Wed Apr 22 2026

High pressure will bring continued dry weather and warm conditions
to the region through Thursday. Mostly sunny skies are expected
today, with increasing clouds on Thursday ahead of an approaching
low pressure system. Warm air advection ahead of the low will push
high temperatures to around 80 degrees west of the Fox Valley
Thursday afternoon, with cooler temperatures near the lake.
Showers and thunderstorms with the approaching low continue to
trend slower, with dry weather expected through Thursday. The warm
and dry conditions today will push relative humidities down to 20
to 30 percent, which will result in a slight uptick in wildfire
potential; however, this will be mitigated by light wind speeds.

The low will eventually bring a swath of showers and thunderstorm
Thursday night and Friday as a cold front moves through the
region. Although MUCAPEs have increased a bit this run, with
values around 1000 J/kg, CAPE profiles are very long, skinny and
stretched out. Therefore, severe weather is not anticipated across
our area with this upcoming system. What is expected is possible
heavy rain at times as probabilities for rain have ticked upwards
this run. The probability of an inch or more of rain is up to 20
to 40%, with around a 10% chance of 2 inches or more of rain
across central Wisconsin. Any additional rainfall is obviously
problematic for flooding, especially if areas receive 2 inches.

After a dry weekend, another low pressure system will bring
another swath of showers and thunderstorms into the region Monday
and Tuesday. Recent model runs have increased the potential for
heavy rain with this system as the probability for an inch or more
of rain is 30-50% south of Rhinelander with a 10-20% of 2 inches
or more.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1052 PM CDT Tue Apr 21 2026

VFR flying conditions will persist through the TAF period.

Clear skies are anticipated through most of the TAF period, though
low clouds currently moving into northern MO are expected to push
into the southwest part of the forecast area late Wed evening,
perhaps reaching CWA/AUW by 05z/Thu. Light NE winds are expected
across the region overnight, but should increase from the E-SE by
late Wednesday morning.

LLWS will edge into NC WI late in the TAF period, though it should
remain northwest of the RHI TAF site.

&&

.HYDROLOGY...
Issued at 1257 AM CDT Wed Apr 22 2026

Minor to moderate flooding continues on many rivers, with major
flooding expected to persist on parts of the Wolf River through
this morning. Most of the river levels have crested, and with a
prolonged stretch of dry weather anticipated through Thursday,
water levels should gradually subside through the week.

Those living near rivers should continue to monitor the latest
Flood Warnings and statements from the National Weather Service
in Green Bay.

&&

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

&&

$$

DISCUSSION.....Kurimski
AVIATION.......Kieckbusch
HYDROLOGY......Kurimski