River Flood Warning 29, NWS Green Bay, WI

Area Forecast Discussion
National Weather Service Green Bay WI
613 AM CDT Tue Apr 14 2026

Updated aviation portion for 12Z TAF issuance

.KEY MESSAGES...

- There is a risk for severe weather south of a Wisconsin Rapids
  to Sturgeon Bay line this afternoon and evening. Large hail and
  damaging winds are the main hazards. There is also an isolated
  tornado threat south of HWY 10.

- Thunderstorms will lead to localized heavy rainfall, greater
  than 1", this afternoon and evening across central and east-
  central WI. This will lead to additional flood concerns through
  tonight.

- Minor to moderate river flooding is ongoing or forecast to occur
  on several area rivers. Expect many rivers to rise this week due
  to additional rain and runoff from Upper Michigan, with the
  greatest impacts expected on the Menominee River, where some
  locations may see major flooding during the mid to late part of
  the week.

- Addtioanl rounds of rain and thunderstorms are expected at
  times Wednesday through this weekend.

&&

.DISCUSSION...
Issued at 310 AM CDT Tue Apr 14 2026

This morning...

Stratiform rain will come to an end from west to east early this
morning as a LLJ shifts east. Dry conditions will then prevail
through the rest of the morning. Behind the rain areas of fog are
expected to develop across much of the region with the lowest
visibilities, under 1/2 mile, across northern WI.

Severe storm potential late this afternoon/evening...

Last nights MCS has layed-out out an outflow boundary along the WI/IL
border early this morning. Persistent southwest flow south of the
boundary will help lift this boundary north as an effect warm front
through the morning and afternoon. CAMs generally show the boundary
stalling along HWY 21 this afternoon with SBCAPES increasing to
~2000 J/kg south of boundary. This will provide the focus for
convective initiation this afternoon, around 3-5PM. With cloud layer
winds out of the southwest storms will cross over to the cool side
of the boundary as they move into Fox Vally and east-central WI.
This along with straight and elongated hodographs will lead to a
large hail (1-2") threat. A damaging wind threat (gusts up to 60
mph) will also be possible this evening if storms grow upscale.
Tornado threat will primarily be focused across southern WI where
low-level lapse rates will be steeper beneath an eroding EML,
however, any storms that can latch onto the boundary and take
advantage of the increased low-leve shear may pose a tornado threat,
greatest chance would be south of HWY 10. The greatest uncertainty
with the severe threat is the positions of the effective warm front,
as a shift further north or south would change the areas of focus
for severe storms. Convection will also result in localized heavy
rainfall. HREF probs show pockets of 50-70% chances for over 1" of
rain across the central and east-central WI. With on-going
flooding and saturated soils this will exacerbate both aerial and
river flooding concerns.

Rain and thunderstorms Wednesday-Monday...

A surface low is forecast to lift into the western Great Lakes
Wednesday bringing another round of rain and possible thunderstorms.
There is uncertainty with how much instability will be able to
recover from Tuesday evenings convection. Latest CAMs and ML/AI
guidance shunts most of the instability south of the CWA. This would
limit the severe threat, however, there is a 25-30% chance for
another .5" of rain which would cause any ongoing flood concerns to
continue.

A more dynamic trough is slated to impact the region late Friday
into the weekend bringing additional widespread rainfall and storms.
The northward extent of greater instability is somewhat uncertain
with this system, impacting severe weather potential, but this will
be something to watch in the coming days. Drier and cooler weather
is expected behind this system for early next week.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 613 AM CDT Tue Apr 14 2026

A blanket of LIFR status has developed across much of the region
along with areas of fog creating locally reduced visibility under
1SM. Cigs should gradually rise this morning with most terminals
becoming MVFR by early afternoon. Next round of rain and
thunderstorms will lift into central and east-central WI late this
afternoon (after 4PM). The best chance scattered severe storms will
be south of an ISW to GRB to SUE line with large hail and damaging
wind gusts the main hazards. Once storms depart (after 11PM) another
round of fog and low clouds is expected into Wednesday morning.

&&

.HYDROLOGY...
Issued at 310 AM CDT Tue Apr 14 2026

MRMS QPE from the last 24-hours shows a maximum of 4.5-5.5 inches of
rainfall along an axis from Stevens Point to Bonduel with a more
broad swath of 1-3"  south of HWY 8. The result has been rapidly
rising rivers and streams along with on-going flash flooding. An
additional 0.5-1" of rain is expected across this area today which
will only exacerbate flooding concerns. Runoff from snow melt in
Upper Michigan is also still expected to bring moderate to possibly
major flooding on the Menominee River, especially during the mid to
late part of the week. If you live near a river or stream, keep a
close eye on water levels this week and monitor the latest Flood
Warnings from the National Weather Service in Green Bay.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Wednesday morning for WIZ022-035>040-045-
048>050.
&&

DISCUSSION.....GK
AVIATION.......GK
HYDROLOGY......GK

Hazardous Weather Outlook
National Weather Service Green Bay WI
401 AM CDT Tue Apr 14 2026

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-150915-
Vilas-Oneida-Forest-Florence-Northern Marinette County-Lincoln-
Langlade-Menominee-Northern Oconto County-Door-Marathon-Shawano-
Wood-Portage-Waupaca-Outagamie-Brown-Kewaunee-Waushara-Winnebago-
Calumet-Manitowoc-Southern Marinette County-
Southern Oconto County-
401 AM CDT Tue Apr 14 2026

This Hazardous Weather Outlook is for north-central and northeast
Wisconsin.

.DAY ONE...Today and Tonight

There is a chance for severe thunderstorms and locally heavy
rainfall south of a line from Wisconsin Rapids to Sturgeon bay
late this afternoon and evening. Large hail and strong winds will
be the primary threats. Isolated tornados are also possible south
of Highway 10.

Ongoing flooding will continue today due to heavy rainfall from
yesterday, especially near rivers, streams, and creeks.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Additional thunderstorms are possible Wednesday afternoon into
Wednesday night, and again Friday night into Saturday.

Elevated water levels and at least minor flooding will continue
along many rivers through the week. Runoff from the Upper
Peninsula will likely result in moderate to possibly major flooding
on the Menominee River during the mid to late part of the week.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to report any flooding to the National
Weather Service in Green Bay.

LMZ521-522-541>543-150915-
The Bay of Green Bay south of a line from Cedar River MI to Rock
Island Passage-Lake Michigan from Washington Island to Sheboygan-
401 AM CDT Tue Apr 14 2026

This Hazardous Weather Outlook is for portions of northwest Lake
Michigan and the waters of Green Bay.

.DAY ONE...Today and Tonight

Thunderstorms, some possibly strong to severe, are expected
tonight.

Areas of fog are possible today.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Thunderstorms will be possible at times Wednesday night, and
again Friday night into Saturday.

GK

Preliminary Local Storm Report
National Weather Service Green Bay WI
626 AM CDT Tue Apr 14 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0555 AM     Rain             1 ENE Clintonville      44.62N 88.73W
04/14/2026  M4.00 Inch       Waupaca            WI   AWOS

            AWOS station KCLI Clintonville Airport.

0620 AM     Rain             Langes Corners          44.39N 87.86W
04/14/2026  M3.48 Inch       Brown              WI   Mesonet

            Mesonet station AW426 Denmark.

0618 AM     Rain             Slovan                  44.53N 87.58W
04/14/2026  M3.20 Inch       Kewaunee           WI   Emergency Mngr

0618 AM     Rain             2 NW Howard             44.58N 88.09W
04/14/2026  M3.03 Inch       Brown              WI   Mesonet

            Mesonet station CW6791 Green Bay.

0615 AM     Rain             4 SE Rose Lawn          44.54N 88.25W
04/14/2026  M2.97 Inch       Outagamie          WI   Mesonet

            Mesonet station DW7584 Seymour.

0620 AM     Rain             1 S De Pere             44.44N 88.05W
04/14/2026  M2.87 Inch       Brown              WI   Mesonet

            Mesonet station AR618 De Pere.

0614 AM     Rain             2 NW Knowlton           44.73N 89.70W
04/14/2026  M2.61 Inch       Marathon           WI   Mesonet

            Mesonet station FW4564 Knowlton.

0453 AM     Rain             2 E Sampson             44.76N 88.13W
04/14/2026  M2.57 Inch       Oconto             WI   Public

0615 AM     Rain             5 W Stratford           44.81N 90.17W
04/14/2026  M2.54 Inch       Marathon           WI   Mesonet

            Mesonet station 7344D Stratford 4 W.

0615 AM     Rain             1 WSW Sturgeon Bay      44.83N 87.40W
04/14/2026  M2.44 Inch       Door               WI   Mesonet

            Mesonet station 3592D Potawatomi State Park
            3 SE.

0616 AM     Rain             2 WNW Evergreen         44.86N 89.68W
04/14/2026  M2.42 Inch       Marathon           WI   Mesonet

            Mesonet station DW7529 Mosinee.

0615 AM     Rain             4 NNE Greenleaf         44.37N 88.07W
04/14/2026  M2.39 Inch       Brown              WI   Mesonet

            Mesonet station DW9271 De Pere.

0600 AM     Rain             2 E Athelstane          45.42N 88.06W
04/14/2026  M2.37 Inch       Marinette          WI   CO-OP Observer

            CO-OP Observer station ASTW3 Athelstane 1.6
            E.

0616 AM     Rain             2 WSW De Pere           44.44N 88.09W
04/14/2026  M2.36 Inch       Brown              WI   Mesonet

            Mesonet station GW3605 De Pere.

0615 AM     Rain             3 ENE Spencer           44.77N 90.21W
04/14/2026  M2.35 Inch       Marathon           WI   Mesonet

            Mesonet station 1500D Spencer 3 E.

0600 AM     Rain             4 ENE Green Bay         44.53N 87.92W
04/14/2026  M2.25 Inch       Brown              WI   Cocorahs

            Cocorahs station WI-BN-41 Green Bay 3.3 E.

0615 AM     Rain             3 WSW Jordan            44.55N 89.53W
04/14/2026  M2.23 Inch       Portage            WI   AWOS

            AWOS station KSTE Stevens Point Airport.

0620 AM     Rain             Denmark                 44.35N 87.83W
04/14/2026  M2.20 Inch       Brown              WI   Mesonet

            Mesonet station DNMRK Denmark 1 NNE.

0620 AM     Rain             Wrightstown             44.33N 88.17W
04/14/2026  M2.09 Inch       Brown              WI   Mesonet

            Mesonet station EW9763 Wrightstown.

0617 AM     Rain             1 SSE Vesper            44.47N 89.95W
04/14/2026  M2.08 Inch       Wood               WI   Mesonet

            Mesonet station EW7537 Vesper.

0605 AM     Rain             6 SW Moon               44.70N 89.87W
04/14/2026  M2.07 Inch       Marathon           WI   Mesonet

            Mesonet station MNEW3 Moon 6 SW.

0624 AM     Rain             Underhill               44.88N 88.38W
04/14/2026  M1.50 Inch       Oconto             WI   Public

&&

Preliminary Local Storm Report
National Weather Service Green Bay WI
755 AM CDT Tue Apr 14 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0733 AM     Flood            2 SSW Marion            44.63N 88.90W
04/14/2026                   Waupaca            WI   Emergency Mngr

            Multiple roads remain closed over Waupaca
            County from Big Falls to Clintonville.

&&

Preliminary Local Storm Report
National Weather Service Green Bay WI
803 AM CDT Tue Apr 14 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 AM     Rain             Clintonville            44.61N 88.75W
04/14/2026  M3.68 Inch       Waupaca            WI   Trained Spotter

            Rain total from Monday evening and
            overnight.

&&

KLJ

Preliminary Local Storm Report
National Weather Service Green Bay WI
833 AM CDT Tue Apr 14 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0700 AM     Rain             Two Rivers              44.15N 87.56W
04/14/2026  M1.41 Inch       Manitowoc          WI   Public

&&

Special Weather Statement
National Weather Service Green Bay WI
849 AM CDT Tue Apr 14 2026

WIZ013-022-039-040-050-073-074-141700-
Northern Marinette County-Door-Brown-Kewaunee-Manitowoc-
Southern Marinette County-Southern Oconto County-
849 AM CDT Tue Apr 14 2026

...REDUCED VISIBILITY IN AREAS OF DENSE FOG THIS MORNING...

Areas of localized dense fog with visibilities as low as one half
to one quarter mile at times this morning along the bay and
lakeshore areas. Motorists should stay alert for localized areas
of reduced visibility this morning. If driving, allow yourself
extra time to reach your destination and use low beam headlights.

Kruk

Preliminary Local Storm Report
National Weather Service Green Bay WI
900 AM CDT Tue Apr 14 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 AM     Rain             3 SW De Pere            44.42N 88.09W
04/14/2026  M2.53 Inch       Brown              WI   Trained Spotter

            24 hour rainfall total.

&&

KLJ