Severe Thunderstorm Warning 67, NWS Milwaukee, WI

684 
WWUS53 KMKX 282026
SVSMKX

Severe Weather Statement
National Weather Service Milwaukee/Sullivan WI
326 PM CDT TUE AUG 28 2018

WIC021-047-077-282045-
/O.CON.KMKX.SV.W.0067.000000T0000Z-180828T2045Z/
Green Lake WI-Columbia WI-Marquette WI-
326 PM CDT TUE AUG 28 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 PM CDT
FOR GREEN LAKE...NORTHEASTERN COLUMBIA AND MARQUETTE COUNTIES...

At 326 PM CDT, severe thunderstorms were located along a line
extending from near Redgranite to 7 miles west of Markesan to near
Pardeeville, moving east at 30 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Emergency management.  70 MPH winds were reported in the 
         Kingston area.  Tree damage was reported south of Montello. 

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
Berlin, Randolph, Montello, Markesan, Princeton, Green Lake,
Packwaukee, Manchester, Endeavor, Neshkoro, Friesland, Kingston,
Marquette, Glen Oak, Harrisville and Dalton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with these storms.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 4398 8889 4363 8889 4363 8900 4357 8901
      4358 8950 4398 8947
TIME...MOT...LOC 2026Z 272DEG 25KT 4398 8914 4373 8913 4357 8931 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...70MPH
 
$$

BOXELL

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
124 PM CDT Tue Aug 28 2018

.UPDATE...

That lone supercell that tracked across northern Iowa weakened
just as it got into southwest WI late this morning. Warm air
advection is causing scattered showers and thunderstorms over
northeast Iowa early this afternoon. The scattered convection
across northern Illinois is due to a remnant outflow boundary.
These should keep tracking east instead of north.

So while we still might get a few showers and thunderstorms across
south central WI this afternoon, the stronger storms are going to
develop just ahead of the surface front, roughly from La Crosse to
northeast WI near Menominee. This is associated with the currently
strong southwesterly flow aloft and steeper mid level lapse rates.
This convection is expected to organize into a broken line by late
afternoon and slide east, possibly clipping the MKX forecast area
(Marquette to Sheboygan County). The strongest forcing will
gradually slide southeast into the MKX forecast area late this
afternoon so either the central WI line will slide south or we
will see additional scattered thunderstorms develop (per the
latest HRRR). We will continue to see rounds of thunderstorms
until just after midnight until the 850mb front gets through
southeast WI.

With the strong instability and shear over southern WI today,
large hail and damaging winds are threats. Tornadoes that develop
along the leading edge of bowing line segments are possible given
strong 0-3km bulk shear. The storm motion will be east-northeast
which is almost parallel to the front, thus the heavy rain and
flash flood threat due to likelihood of training thunderstorms. A
severe thunderstorm watch was just issued.

&&

.AVIATION(18Z TAFS)...

MVFR ceilings will persist through late afternoon. We should see
some improvement in ceilings, but there will still be a few MVFR
cloud bases around given our very moist environment. Look for
thunderstorms to develop by late afternoon. They may be severe
with wind and hail and will also have high rainfall rates. A
tornado is possible.

Thunder should taper off after midnight, but showers and isolated
thunderstorms may linger until after sunrise Wed morning. MVFR
ceilings behind the storms overnight into Wed morning will
gradually rise to VFR by early afternoon.

&&

.PREV DISCUSSION... (Issued 959 AM CDT Tue Aug 28 2018)

UPDATE...

We added a county to our flash flood watch to line up better with
NWS Quad Cities. They have a good chance of seeing multiple rounds
of thunderstorms tonight. We will continue to consider adding the
rest of southeast WI into the watch, but they have not had quite
as much rain lately.

There is a well-organized supercell that is rolling across
northern Iowa this morning. It produced 1 to 1.75 inch hail in
northeast Iowa just recently. The latest HRRR has that storm
weakening as it gets into south central WI, but we're not so
certain that will happen given the strong instability and shear
over the area. If it holds together and keeps its current
movement/track, it would reach Lone Rock at 11:30 am and just
north of Madison at 12:30 pm.

All eyes are on the multiple rounds of thunderstorms expected late
this afternoon and through the evening hours across southern
Wisconsin. The Flash Flood Watch is still appropriate. There is
now an Enhanced Risk by SPC across all of southern WI. This
upgrade is due to the expected strong instability and shear over
our area. Damaging winds are expected, large hail is likely in a
few spots, and brief spin-up tornadoes will be possible along line
segments.

MARINE...A Small Craft Advisory is in effect today for breezy
sswly winds that will develop later this morning. Lighter wind and
waves, along with quiet weather, are expected Wednesday and
Thursday.

PREV DISCUSSION... (Issued 453 AM CDT Tue Aug 28 2018)

SHORT TERM...

Today and Tonight...Forecast Confidence is high.

The low level jet will weaken toward sunrise with a gradual
reduction in precipitation coverage expected. Partly cloudy skies
should occur for a time before more thunderstorms develop. Moderate
values of CAPE and shear will be present once again with more SVR
storms expected. The nose of the low level jet will develop nwd into
srn WI by middle to late afternoon while a vorticity maximum
approaches from IA, and another stronger shortwave trough moves
across the nrn Great Plains. At the surface, a cold front will
approach central WI by middle to late afternoon and then gradually
move across srn WI tnt. Although organized lines of storms will be
progressive, some areas will likely see rounds of storms. 1.5-2
inches of rain is forecast but locally several inches will be
possible. Thus the Flash Flood Watch continues until 12z Wed.

LONG TERM...

Wednesday and Thursday...Forecast confidence is medium to high:

A few showers may hang into Wednesday morning, but it should turn
dry by mid to late morning. Clouds will hang on into the
afternoon, with some sunshine possible by mid or late afternoon.
It will be considerably cooler on Wednesday, with high
temperatures struggling to hit 70 most places.

Could see some fog Wednesday night as high pressure moves
overhead. The high will bring pleasant weather on Thursday, with
mostly sunny skies and temps in the low 70s.

Thursday night through Monday...Forecast confidence is medium:

A couple of forecast models are now showing a shortwave pushing
into the area later Thursday night into Friday morning, much
quicker than what models have been showing. There are models that
still hold onto the high longer into Friday though, so some
uncertainty with this period. The better chance for storms should
come Friday night into Saturday as the main low and associated
front move through.

It should be dry Sunday under high pressure, with more storm
chances returning Monday.

Temperatures should be within a few degrees of normal late this
week into early next week.

AVIATION(12Z TAFS)...Areas of IFR and MVFR Cigs near convection
or outflow boundaries early this morning. Otherwise the
thunderstorms will end later this morning with partly cloudy skies
via cumulus for late morning and afternoon. However, more rounds of
showers and thunderstorms will develop for the middle to late
afternoon into the evening. Widespread stratus will then move into
the area late tnt behind the cold front.

MARINE...A Small Craft Advisory is in effect today for breezy
sswly winds that will develop later this morning.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Flash Flood Watch through Wednesday morning for WIZ046-047-051-
     052-056>060-062>068.

LM...Small Craft Advisory until 7 PM CDT this evening for LMZ643>646.

&&

Update...Cronce
Today/Tonight and Aviation/Marine...Gehring
Wednesday THROUGH Monday...DDV

Hazardous Weather Outlook...UPDATED
National Weather Service Milwaukee/Sullivan WI
1001 AM CDT Tue Aug 28 2018

WIZ046-047-051-052-056>060-062>072-291100-
Marquette-Green Lake-Fond Du Lac-Sheboygan-Sauk-Columbia-Dodge-
Washington-Ozaukee-Iowa-Dane-Jefferson-Waukesha-Milwaukee-
Lafayette-Green-Rock-Walworth-Racine-Kenosha-
1001 AM CDT Tue Aug 28 2018

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

.DAY ONE...Today and Tonight

More rounds of thunderstorms are likely later today through
tonight. There will be a threat for severe thunderstorms and heavy
rainfall once again. The possible heavy rain will result in a
risk for flooding, especially for areas that have seen very heavy
rain over the last week or so. A Flash Flood Watch is in effect
for parts of the region into early Wednesday morning.

Heat index values may reach the middle 90s today.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

A chance for thunderstorms will return for late Thursday night
through Saturday and again on Monday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed this afternoon into
tonight.

LMZ643>646-291100-
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-
1001 AM CDT Tue Aug 28 2018

This Hazardous Weather Outlook is for portions of Lake Michigan.

.DAY ONE...This Afternoon and Tonight

A Small Craft Advisory remains in effect into early this evening
for gusty south to southwest winds.

Thunderstorms are likely again later this afternoon into tonight.
Severe thunderstorms will be possible once again later today.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

A chance for thunderstorms will return for Friday night and
Saturday, and then again on Monday.

Cronce

www.weather.gov/mkx

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1048 AM CDT TUE AUG 28 2018

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

0756 AM     HEAVY RAIN       THERESA                 43.51N 88.46W
08/28/2018  M1.81 INCH       DODGE              WI   PUBLIC

1229 AM     HEAVY RAIN       2 S BERLIN              43.94N 88.94W
08/28/2018  M3.50 INCH       GREEN LAKE         WI   PUBLIC

1200 AM     HEAVY RAIN       2 N KOHLER              43.76N 87.77W
08/28/2018  M3.10 INCH       SHEBOYGAN          WI   PUBLIC

&&