Flash Flood Warning 11, NWS Milwaukee, WI

900 
WGUS73 KMKX 230516
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
1216 AM CDT Fri Oct 23 2020

WIC021-025-049-111-231000-
/O.CON.KMKX.FF.W.0011.000000T0000Z-201023T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Columbia WI-Dane WI-Iowa WI-Sauk WI-
1216 AM CDT Fri Oct 23 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 AM CDT EARLY THIS 
MORNING FOR SOUTHWESTERN COLUMBIA, NORTHWESTERN DANE, NORTHERN IOWA 
AND SOUTHERN SAUK COUNTIES...

At 1216 AM CDT, local law enforcement reported flowing water over a 
few roads across the warned area. Doppler radar estimates between 3 
and 5 inches of rain have fallen. Flash flooding is already 
occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement and doppler radar.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other
         drainage and low lying areas.

Some locations that will experience flash flooding include...
  Prairie Du Sac, Sauk City, Lake Wisconsin, Lodi, Poynette, 
  Mazomanie, Spring Green, Black Earth, Dane, Highland, Arena, 
  Arlington, Plain, Bluffview, Avoca, Merrimac, Clyde, Marxville, 
  Devils Lake St Park and Okee.

Additional rainfall amounts of 1 to 1.5 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4316 9019 4329 9019 4351 8952 4342 8922
      4316 8966 4295 9043 4320 9043 4321 9030

FLASH FLOOD...OBSERVED

$$

GEHRING

952 
WGUS73 KMKX 230646
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
146 AM CDT Fri Oct 23 2020

WIC021-025-049-111-231000-
/O.CON.KMKX.FF.W.0011.000000T0000Z-201023T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Columbia WI-Dane WI-Iowa WI-Sauk WI-
146 AM CDT Fri Oct 23 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 AM CDT EARLY THIS 
MORNING FOR SOUTHWESTERN COLUMBIA, NORTHWESTERN DANE, NORTHERN IOWA 
AND SOUTHERN SAUK COUNTIES...

At 146 AM CDT, Doppler radar indicated showers and thunderstorms 
producing moderate rain across the warned area. Between 3 and 5 
inches of rain have fallen. Flash flooding is already occurring with 
a few flooded roads across the area.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Doppler radar and law enforcement

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other
         drainage and low lying areas.

Some locations that will experience flash flooding include...
  Prairie Du Sac, Sauk City, Lake Wisconsin, Lodi, Poynette, 
  Mazomanie, Spring Green, Black Earth, Dane, Highland, Arena, 
  Arlington, Plain, Bluffview, Avoca, Merrimac, Clyde, Marxville, 
  Devils Lake St Park and Okee.

Additional rainfall amounts of 0.5 to 1 inch are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4316 9019 4329 9019 4351 8952 4342 8922
      4316 8966 4295 9043 4320 9043 4321 9030

FLASH FLOOD...RADAR INDICATED

$$

GEHRING

379 
WGUS73 KMKX 230956
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
456 AM CDT Fri Oct 23 2020

WIC021-025-049-111-231006-
/O.EXP.KMKX.FF.W.0011.000000T0000Z-201023T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Columbia WI-Dane WI-Iowa WI-Sauk WI-
456 AM CDT Fri Oct 23 2020

...FLASH FLOOD WARNING WILL EXPIRE AT 5 AM CDT EARLY THIS MORNING 
FOR SOUTHWESTERN COLUMBIA, NORTHWESTERN DANE, NORTHERN IOWA AND 
SOUTHERN SAUK COUNTIES...

Flash flooding is no longer expected to pose a threat. Please 
continue to heed remaining road closures.

LAT...LON 4316 9019 4329 9019 4351 8952 4342 8922
      4316 8966 4295 9043 4320 9043 4321 9030

$$

MBK

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1032 PM CDT Thu Oct 22 2020

.UPDATE...
(Issued 1032 PM CDT Thu Oct 22 2020)

A wave of low pressure will slide across far se WI and srn Lake MI
over the next several hours. The sw-ne oriented heavy rainfall
within strong 925-850 mb frontogenesis will gradually shift into
ern WI but CAMs do show some weakening after 06Z. Minor flooding
of streams and urban areas will remain possible where 2-4 inches
of rain fall, but cannot completely rule out flash flooding in
large urban areas. Another round of showers and storms may
organize and move across srn WI from 11Z-17Z Fri as the shortwave
trough currently over WY approaches WI.

Gehring

&&

.SHORT TERM...
(Issued 315 PM CDT Thu Oct 22 2020)

Tonight and Friday:

Precip continues to diminish as the bulk of the showers and
thunderstorms lift north with the low-level/850mb warm frontal
boundary into central WI this afternoon. Low-level clouds and patchy
fog will linger behind the shower activity and will continue
until the passage of the surface warm front, which is progressing
northward into northern IL. Based on current observations and
satellite trends, we should begin to see some breaks in the
clouds and increasing visibilities for areas south of I-94 later
this afternoon/evening. This will aid in temps rising into the
upper 50s to low 60s, while areas generally north of I-94 will
stay cooler in the mid to upper 40s.

As the front pushes further north this evening, it is expected to
stall across the central portion of the CWA as a surface low lifts
into IA then WI from the Central Plains. As the low pushes northeast
into southern WI later this evening, another round of rain and
thunderstorms will accompany it supported by lift from 700mb
frontogenesis and the cold front. With a stronger jet setting up
and moving in with this system, expect decent deep layer shear
exceeding 40 kt to develop and combined with MUCAPE creeping to
around 500-750 J/kg, can not rule a stronger storm or two with any
thunderstorm activity this evening. Most models and ensemble
members support an additional 0.5 to 1.0 inch of rainfall this
evening and overnight. Locally higher amounts exceeding 1.5 inch
will be possible and given previous rainfall localized flooding
could be possible as well, but given the quick moving nature of
this system not expecting it to be too much of a concern.

Otherwise, rain will gradually move east as the cold front pushes
through the area Friday morning/afternoon. Breezy north-
northwesterly winds will develop in its wake, but drier and
cooler conditions are expected later in the day on Friday as high
pressure begins to build into the northern Plains and Upper
Midwest. Looking at highs to top off only in the 40s for Friday.

Wagner

&&

.LONG TERM...
(Issued 303 PM CDT Thu Oct 22 2020)

Friday night through Thursday:

Friday night and Saturday:

Clouds are expected to gradually clear Friday night into Saturday
as high pressure pushes in from the west, though clouds may hang
on for a while in the west. Quiet weather is expected through
Saturday, with increasing mid to high level clouds by the
afternoon. Well below normal temperatures are likely Saturday,
with highs only topping out in the low to mid 40s.

Sunday and Sunday night:

Surface low pressure is progged to pass by well to the south on
Sunday. A fair amount of warm advection is expected across the
area Sunday along with a shortwave Sunday night, bringing precip
chances to southern Wisconsin. Still some disagreement among
models with how much of a warm push there will be into southern
Wisconsin, but it seems the southeast forecast area will have a
decent chance at some rain vs snow. Given the current spread of
model solutions, the northwest forecast area may see mainly light
snow. Still a lot of time for the details to change, with models
ranging from mainly rain across the entire forecast area via the
NAM, to all snow via the GFS. Overall combination of
forcing/moisture not very impressive, so any snowfall
accumulations would likely be on the light side.

Monday through Thursday:

Well below normal temperatures will continue next week, with
mainly dry weather expected through Thursday (aside from any
lingering precip early Monday).

DDV

&&

.AVIATION...
(Issued 1032 PM CDT Thu Oct 22 2020)

Areas of dense fog over se WI will end by 06Z, but Cigs will
mostly remain below 1 kft tnt-Fri AM then rise to 1-3 kft for the
afternoon. Rounds of heavy rain will limit vsbys to 1-3SM tnt-Fri
AM. Modest to brisk nly winds will become established tnt and
continue on Fri.

Gehring

&&

.MARINE...
(Issued 320 PM CDT Thu Oct 22 2020)

Breezy southerly winds and building waves are developing across
southern portions of the Lake this afternoon as a warm frontal
boundary slowly lifts north into the area. Thus, a small craft
advisory remains in effect through Friday. Patchy fog will also
be possible across our nearshore waters at times through Friday
morning as well. Then as the warm front gradual lifts a bit
further north this evening, a surface low will track up through
the Central Plains into WI and over north-central Lake Michigan
tonight and bring a cold front with additional showers and
storms through the region. Gusty north to northwesterly winds
will then develop in the wake of the cold front for Friday. Then
high pressure will build into the Upper Midwest for Saturday.

Wagner

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Dense Fog Advisory...WIZ060-WIZ065-WIZ066-WIZ067-WIZ068-WIZ069-
     WIZ070-WIZ071-WIZ072 until midnight Friday.

LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 7 PM
     Friday.

&&

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Hazardous Weather Outlook
National Weather Service Milwaukee/Sullivan WI
928 PM CDT Thu Oct 22 2020

WIZ046-047-051-052-056>060-062>072-240230-
Marquette-Green Lake-Fond du Lac-Sheboygan-Sauk-Columbia-Dodge-
Washington-Ozaukee-Iowa-Dane-Jefferson-Waukesha-Milwaukee-
Lafayette-Green-Rock-Walworth-Racine-Kenosha-
928 PM CDT Thu Oct 22 2020

This Hazardous Weather Outlook is for portions of east central
Wisconsin, south central Wisconsin and southeast Wisconsin.

.DAY ONE...Tonight

Evening and early morning thunderstorms will cause localized
heavy rainfall and possibly some minor street and urban flooding.
Some pea sized hail cannot be ruled out with these storms as well. A
flood advisory is currently in effect for NW Sauk Co. until
530AM.

Locally dense fog is present along the Lake Michigan shoreline and
inland areas over southeast WI. Fog may linger until the midnight
hour for some while areas over far SE WI may improve. A dense fog
advisory is in effect until midnight.

.DAYS TWO THROUGH SEVEN...Friday through Thursday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this evening into tonight.

LMZ643>646-240230-
Sheboygan to Port Washington WI-
Port Washington to North Point Light WI-
North Point Light to Wind Point WI-
Wind Point WI to Winthrop Harbor IL-
928 PM CDT Thu Oct 22 2020

This Hazardous Weather Outlook is for the nearshore waters from
Sheboygan Wisconsin to Winthrop Harbor Illinois.

.DAY ONE...Tonight

Thunderstorms will remain possible into the early morning hours.
Some pea sized hail cannot be ruled out.

A Small Craft Advisory is in effect through tonight mainly due to
lingering high waves.

Dense fog is occuring in nearshore locales and may linger into
the early morning hours. A dense fog advisory is in effect until
midnight

.DAYS TWO THROUGH SEVEN...Friday through Thursday

The Small Craft Advisory remains in effect on Friday for gusty
northwest winds to 25 knots.

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-240230-
Lake Michigan Michigan City IN to St. Joseph MI 5 NM offshore to
mid-line of lake.-
Lake Michigan from Seul Choix Point to Rock Island Passage 5NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and North of a line from Charlevoix MI to South
Fox Island 5NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5NM Offshore to
mid lake-
Lake Michigan from Point Betsie to Manistee MI 5NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI 5NM
offshore to mid lake-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5NM offshore to Mid
Lake-
Lake Michigan from Sheboygan to Port Washington WI 5NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor to Michigan City in 5NM
offshore to Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5NM offshore to Mid
Lake-
Lake Michigan from Whitehall to Pentwater MI 5NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5NM offshore to Mid
lake-
Lake Michigan from St Joseph to South Haven MI 5NM offshore to
Mid Lake-
928 PM CDT Thu Oct 22 2020

This Hazardous Weather Outlook is for the open waters of Lake
Michigan.

.DAY ONE...Tonight

Thunderstorms remain possible tonight over the southern two
thirds of Lake Michigan.

Locally dense fog is possible over the open waters into the early
morning hours.

A few gusts will approach gale force tonight over the northern
lake.

.DAYS TWO THROUGH SEVEN...Friday through Thursday

The chance for thunderstorms will continue into Friday morning
across the southern open waters.

www.weather.gov/mkx