Flash Flood Warning 7, NWS Green Bay, WI

785 
WGUS53 KGRB 172332
FFWGRB
WIC073-141-180215-
/O.EXT.KGRB.FF.W.0007.000000T0000Z-260418T0215Z/
/00000.U.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Green Bay WI
632 PM CDT Fri Apr 17 2026

The National Weather Service in Green Bay has extended the

* Flash Flood Warning for...
  South Central Marathon County in central Wisconsin...
  Northwestern Wood County in central Wisconsin...

* Until 915 PM CDT.

* At 632 PM CDT, local law enforcement reported thunderstorms
  producing heavy rain across the warned area. Between 1.5 and 2.5
  inches of rain have fallen. Flash flooding is ongoing or expected
  to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms producing
           flash flooding.

  SOURCE...Law enforcement reported.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses. Many roads
           are reported under water in Marshfield.

* Some locations that will experience flash flooding include...
  Marshfield, Hewitt, Auburndale, Arpin, Bethel, Powers Bluff County
  Park, North Wood County Park, Bakerville, Nasonville, Rozellville,
  Lindsey and Big Eau Pleine County Park.

This includes the following streams and drainages...
  Hemlock Creek, Wild Creek, Cat Creek, Mill Creek, Freeman Creek,
  Yellow River, Wisconsin River, Little Hemlock Creek, Scheuer Creek,
  East Fork Black River, Squaw Creek, Beaver Creek, Little Bear
  Creek, South Branch Yellow River, Hay Creek, East Fork Hemlock
  Creek, Rocky Run, Puff Creek and East Branch Yellow River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4469 9018 4477 9003 4475 8980 4450 9008
      4439 9032 4460 9032 4466 9023

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

JLA

159 
WGUS73 KGRB 180211
FFSGRB

Flash Flood Statement
National Weather Service Green Bay WI
911 PM CDT Fri Apr 17 2026

WIC073-141-180221-
/O.EXP.KGRB.FF.W.0007.000000T0000Z-260418T0215Z/
/00000.U.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Marathon WI-Wood WI-
911 PM CDT Fri Apr 17 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 915 PM CDT THIS EVENING FOR
SOUTH CENTRAL MARATHON AND NORTHWESTERN WOOD COUNTIES...

The heavy rain has ended. Flood waters have receded or will slowly
recede. Flash flooding is no longer expected to pose a threat. Please
continue to heed remaining road closures.

A Flood Watch remains in effect until 700 AM CDT Saturday for
portions of central, east central, north central, and northeast
Wisconsin.

&&

LAT...LON 4469 9018 4477 9003 4475 8980 4450 9008
      4439 9032 4460 9032 4466 9023

$$

Bersch

Area Forecast Discussion
National Weather Service Green Bay WI
134 PM CDT Fri Apr 17 2026

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

-Severe storms with a risk of tornadoes (possibly strong), large
 hail and damaging winds are increasingly likely from 3 pm to 8 pm
 today, with the highest risk across central Wisconsin.

-Thunderstorms this afternoon and evening will produce locally
 heavy rainfall. If this occurs over the flood sensitive areas of
 central and east central WI additional significant flooding may
 occur.

-Minor to major flooding will continue into next week with the
 greatest impacts expected on the Menominee and Wolf Rivers where
 major or record breaking flooding has been observed.

-No significant precipitation is expected from Saturday through
 Thursday, but widespread showers and storms may return next Thursday
 night into Friday.

&&

.DISCUSSION...
Issued at 125 PM CDT Fri Apr 17 2026

Severe Thunderstorm and Flood Potential This Afternoon/Evening...
Confidence is increasing in a significant, but fairly brief
severe weather event. A narrow axis of SBCAPE (1500-2500 j/kg)
was already developing ahead of a strong cold front over SE MN, NE
IA and SW WI. This was coincident with 0-1km SRH of 200-250.
Radar showed pre-frontal convection occurring in far SW WI and NE
IA, with additional storms developing along the cold front in
eastern MN. CAMs show intense convection, including supercells and
line segments moving through the forecast area between 3 pm and 8
pm. Given the degree of shear, an all-hazard event, including
tornadoes, is expected, with the tornado threat lessening for any
storms nearing the lakeshore, where less instability will be
present. A Tornado Watch has been issued along and south of Hwy 29
(away from Lake Michigan) through 8 pm. A lingering Severe
Thunderstorm Watch is also still in effect for far NC WI until 5
pm. This will be a fairly short-lived event, as instability drops
off rapidly after sunset. An additional band of light to moderate
showers will accompany the cold front later this evening and
overnight. Expect most locations to see between 0.50 and 1 inch of
precipitation with event, which will exacerbate ongoing flooding.
A Flood Watch remains in effect for all but the far northwest
part of the CWA.

The cold frontal passage will bring a period of cooler weather
through the weekend into early next week. The best chance of
precipitation during this period will be 20-40 percent chance of
snow/rain showers over C/EC WI on Sunday, in association with a
short-wave trough and cold frontal passage.

Mainly dry and warmer weather is expected for the middle of next
week, with high temperatures reaching into the 60s and 70s. An
approaching cold front brings another potentially significant
round of showers and storms Thursday night into Friday.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 628 AM CDT Fri Apr 17 2026

Fog and very low stratus continues near Lake Michigan due to moist
SSE flow off the cold waters. This will likely improve as low-
level winds become southwest this evening, then northwest behind a
cold front overnight.

Thunderstorms storms were develop ahead of a cold front, and are
likely to become severe as they move through the forecast area
between 20z/Fri-01z/Sat. Flight conditions will quickly lower to
MVFR/IFR during the storms, with MVFR and local IFR ceilings
lingering into the late evening and overnight. A second band of
showers will accompany the passage of the cold front tonight.
Expect flight conditions to improve to VFR late tonight into early
Saturday.

South southeast surface winds will gust to 25 to 35 kts this
afternoon, then become NW 15 to 25 kts after the cold front moves
through this evening and overnight. Ahead of the front, periods
of LLWS will continue.

&&

.HYDROLOGY...
Issued at 125 PM CDT Fri Apr 17 2026

A Flood Watch is in effect through tonight, due to an expected
half inch to an inch of rain from thunderstorms this afternoon
and evening. Locally higher amounts are possible.

Flooding continues along multiple rivers due to the combination
of snow melt and recent heavy rainfall, including major flooding
along the Wolf and Menominee Rivers. If you live near a river or
stream, continue to monitor the latest hydro forecasts and Flood
Warnings from the National Weather Service in Green Bay.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Saturday morning for WIZ011>013-019>022-030-
031-035>040-045-048>050-073-074.
&&

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

Hazardous Weather Outlook
National Weather Service Green Bay WI
154 PM CDT Fri Apr 17 2026

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-181900-
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-
154 PM CDT Fri Apr 17 2026

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

.DAY ONE...This Afternoon and Tonight

Thunderstorms, some severe with locally heavy rain, will impact
the area between 3 pm and 8 pm. Hazards include large hail, a few
tornadoes, possibly strong, and damaging winds. The highest
threat is across central Wisconsin.

Flooding may occur with the storms, especially in urban areas,
and locations already impacted by heavy rain earlier in the week.

River flooding is expected to continue due to recent heavy
rainfall, with major flooding on parts of the Wolf and Menominee
Rivers.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Flooding will continue on some area rivers and streams into next
week.

.SPOTTER INFORMATION STATEMENT...

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

LMZ521-522-541>543-181900-
The Bay of Green Bay south of a line from Cedar River MI to Rock
Island Passage-Lake Michigan from Washington Island to Sheboygan-
154 PM CDT Fri Apr 17 2026

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

.DAY ONE...This Afternoon and Tonight

Areas of dense fog are expected through late tonight. A Dense Fog
Advisory is in effect for the Lake Michigan nearshore waters and
the bay of Green Bay.

Thunderstorms will occur later this afternoon and evening. Any
thunderstorms could be hazardous to boaters.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

The probability for widespread hazardous weather is low.

Kieckbusch

Preliminary Local Storm Report
National Weather Service Green Bay WI
335 PM CDT Fri Apr 17 2026

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

0324 PM     Hail             1 NW Marshfield         44.67N 90.17W
04/17/2026  M0.38 Inch       Wood               WI   Cocorahs

            hail report from Cocorahs spotter of 0.375
            with an average of 0.250.

&&

JF

Special Weather Statement
National Weather Service Green Bay WI
340 PM CDT Fri Apr 17 2026

WIZ010-018-172145-
Oneida WI-Lincoln WI-
340 PM CDT Fri Apr 17 2026

...A STRONG THUNDERSTORM WILL IMPACT LINCOLN AND WESTERN ONEIDA
COUNTIES UNTIL 445 PM CDT...

At 340 PM CDT, Doppler radar was tracking a strong thunderstorm 15
miles southwest of Tripoli, or 40 miles northwest of Wausau, moving
northeast at 45 mph.

HAZARD...Wind gusts up to 40 mph and half inch size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

The strong thunderstorm will be near...
  Tripoli around 400 PM CDT. Willow Reservoir around 420 PM CDT.

Other locations impacted by this strong thunderstorm include Spirit
Falls, Mccord, Bradley, Gobler Lake Natural Area, Lower Tomahawk
River Natural Area, Harshaw, Goodnow and Hazelhurst.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

&&

LAT...LON 4556 9004 4572 9004 4590 8968 4545 8943
      4512 9004 4525 9005 4534 9005 4538 9004
TIME...MOT...LOC 2040Z 228DEG 38KT 4538 9021

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

JG

Preliminary Local Storm Report
National Weather Service Green Bay WI
400 PM CDT Fri Apr 17 2026

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

0350 PM     Hail             2 S Hewitt              44.60N 90.13W
04/17/2026  E0.70 Inch       Wood               WI   Public

            weather spotter called in saying 3 miles
            south of marsfeild dime size hail.

&&

JF