Special Weather Statement, NWS Milwaukee, WI

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
235 PM CDT THU AUG10 2017

.TONIGHT AND FRIDAY - Forecast Confidence...High.

Showers and storms are beginning to fire this afternoon as expected.
Storms will be likely into early evening, with some of the storms
possibly reaching severe levels. Large hail and damaging winds are
the main threats.

After storms exit the southeast this evening, dry weather is
expected overnight. Could see a shower or sprinkle tomorrow as the
cooler air aloft moves through, but most places will remain dry.

Below normal temps are likely on Friday, with mostly cloudy skies
lingering much of the day and the cooler airmass aloft moving
through.

.FRIDAY NIGHT THROUGH SUNDAY - Forecast Confidence...Medium to
High.

A mainly dry and comfortable period is expected.  Lingering low to
mid level cyclonic curvature on Saturday will fight against a very
dry atmosphere, so only expecting few-sct cumulus redevelopment.
Hence expecting a mostly sunny day with 925H temps resulting in
daytime temps warming to slightly below seasonal normal. Weak warm
air advection ahead of a slowly moving upper level wave in the
northern Plains may clip far southwest Wisconsin with a few showers
or storms Sunday afternoon.  Otherwise, a bit more cloudiness can be
expected on Sunday due to the proximity of the upstream short wave.
Temperatures on Sunday will be similar to Saturday.

.EXTENDED PERIOD...

SUNDAY NIGHT THROUGH THURSDAY - Forecast Confidence...Medium to
High.

Most of this period is looking dry and seasonal for mid-August.
Persistent down-stream low pressure troffing over eastern Canada
into the eastern Great Lakes will result in dry NNW steering flow
across the western Great Lakes.  Upstream, short wave high pressure
ridging will gradually expand in coverage and intensity and spread
into the western Great Lakes early next week.  925H temps look
seasonal with readings in the 15-18 degree range and resultant
daytime temperatures warming into the 70s to around 80.

Protective ridge should keep southern WI dry at least through
Wednesday.  Medium range guidance in reasonable agreement showing
ridge flattening out due to strong short wave moving ENE through the
northern plains into the western Great Lakes around mid-week. GFS
Ensembles show some variation in the timing of the short wave trof
with several perturbations holding onto lingering ridging.  GFS
increase precipitable water rapidly to around 2 inches Wednesday
night into early Thursday. For now wl include chance pops Wednesday
night into Thursday.

&&

.AVIATION(18Z TAFS)...Thunderstorms are likely this afternoon into
early evening. The main focus will be across the southeast half of
the forecast area. A few of the storms could reach severe levels,
with damaging winds and large hail the main threats.

After storms exit the southeast this evening, dry weather is
expected overnight. Could see a shower or sprinkle tomorrow, but
most places will remain dry.

Lower ceilings are likely later tonight into Friday as cooler air
aloft moves into the area.

&&

.MARINE...Waves could approach 4 feet through late afternoon north
of Port Washington under breezy south winds. Otherwise, winds and
waves are expected to stay below Small Craft Advisory levels the
next several days.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...

WI...None.
LM...None.

TONIGHT AND FRIDAY/AVIATION/MARINE...DDV
FRIDAY NIGHT THROUGH THURSDAY...MBK

Hazardous Weather Outlook
National Weather Service Milwaukee/Sullivan WI
254 PM CDT Thu Aug 10 2017

WIZ046-047-051-052-056>060-062>072-112000-
Marquette-Green Lake-Fond Du Lac-Sheboygan-Sauk-Columbia-Dodge-
Washington-Ozaukee-Iowa-Dane-Jefferson-Waukesha-Milwaukee-
Lafayette-Green-Rock-Walworth-Racine-Kenosha-
254 PM CDT Thu Aug 10 2017

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

.DAY ONE...Late this Afternoon and Tonight

Numerous thunderstorms will rumble across south central and
southeast Wisconsin late this afternoon and this evening. A few
thunderstorms will likely become severe, producing large hail
and/or damaging thunderstorm wind gusts. One or two tornadoes are
also possible.

A Severe Thunderstorm Watch is in effect for most of south central
and southeast Wisconsin until 9 pm CDT.

There is a moderate swim risk late this afternoon into this
evening for Sheboygan and Ozaukee beaches adjacent to Lake
Michigan. Breaking waves and currents are expected. Stay away from
dangerous areas like piers, breakwalls and river outlets.

.DAYS TWO THROUGH SEVEN...Friday through Thursday

There is a small chance for thunderstorms Wednesday night and
Thursday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this afternoon and evening.

LMZ643>646-112000-
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-
254 PM CDT Thu Aug 10 2017

This Hazardous Weather Outlook is for portions of Lake Michigan.

.DAY ONE...Late this Afternoon and Tonight

Numerous thunderstorms will affect the near shore waters into this
evening. A few thunderstorms may become severe, producing damaging
wind gusts and large hail. A Severe Thunderstorm Watch is in
effect until 9 pm CDT.

.DAYS TWO THROUGH SEVEN...Friday through Thursday

There is a chance of thunderstorms next Wednesday night and
Thursday.

www.weather.gov/mkx

MBK

Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
438 PM CDT THU AUG 10 2017

WIZ052-058>060-102215-
Dodge-Sheboygan-Ozaukee-Washington-
438 PM CDT THU AUG 10 2017

...A STRONG THUNDERSTORM WILL AFFECT OZAUKEE...CENTRAL WASHINGTON AND
SOUTHEASTERN SHEBOYGAN COUNTIES...

At 437 PM CDT, a strong thunderstorm was located near Slinger, moving
east at 45 mph.

Wind gusts up to 50 mph and dime size hail are possible with this
storm.

Locations impacted include...
West Bend, Hartford, Grafton, Port Washington, Jackson, Slinger,
Saukville, Oostburg, Belgium, Fredonia, Cedar Grove, Random Lake,
Newburg, Addison, Nenno, Waubeka, Fillmore, Harrington Beach St Park,
Boltonville and Allenton.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 4357 8779 4354 8780 4349 8779 4345 8781
      4338 8787 4333 8789 4327 8835 4345 8841
      4362 8777 4360 8776
TIME...MOT...LOC 2137Z 255DEG 40KT 4339 8828

MBK

Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
445 PM CDT THU AUG 10 2017

WIZ057-058-063-064-102215-
Dodge-Columbia-Jefferson-Dane-
445 PM CDT THU AUG 10 2017

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN DANE AND
NORTHWESTERN JEFFERSON COUNTIES...

At 445 PM CDT, a strong thunderstorm was located over northeastern
Madison, moving east at 20 mph.

Wind gusts up to 50 mph and dime size hail are possible with this
storm.

Locations impacted include...
Eastern Madison, Sun Prairie, Waunakee, Monona, Windsor, Marshall,
Waterloo, Cottage Grove, Deerfield, Deansville, Token Creek and East
Bristol.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 4304 8933 4320 8940 4330 8904 4306 8894
TIME...MOT...LOC 2145Z 255DEG 18KT 4314 8931

MBK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
455 PM CDT THU AUG 10 2017

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

0441 PM     HAIL             WAUPUN                  43.63N 88.74W
08/10/2017  E1.00 INCH       DODGE              WI   PUBLIC

            MULTIPLE PICTURES RELAYED VIA SOCIAL MEDIA.

&&

BSH

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
512 PM CDT THU AUG 10 2017

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

0441 PM     TSTM WND DMG     PLYMOUTH                43.75N 87.97W
08/10/2017                   SHEBOYGAN          WI   LAW ENFORCEMENT

            SEVERAL TREES DOWNED.

&&

BSH

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
521 PM CDT THU AUG 10 2017

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

0448 PM     TSTM WND GST     SHEBOYGAN               43.75N 87.70W
08/10/2017  M41 MPH          LMZ643             WI   C-MAN STATION

            MEASURED AT SHEBOYGAN LAKESHORE WEATHER
            STATION.

&&

MBK

Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
521 PM CDT THU AUG 10 2017

WIZ060-102245-
Ozaukee-
521 PM CDT THU AUG 10 2017

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL OZAUKEE COUNTY...

At 521 PM CDT, a strong thunderstorm was located over Port
Washington, moving northeast at 30 mph.

Winds in excess of 40 mph and half inch hail are possible with this
storm.

Locations impacted include...
Grafton, Port Washington and Saukville.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 4345 8781 4341 8785 4338 8786 4338 8787
      4330 8789 4327 8791 4341 8801 4349 8780
TIME...MOT...LOC 2221Z 245DEG 25KT 4336 8787

MARQUARDT