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181
FXUS63 KMKX 162047
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
347 PM CDT Sun Jun 16 2024

.KEY MESSAGES...

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- Increasing potential for thunderstorms this afternoon/evening
  with strong to severe thunderstorm or two possible bringing
  damaging winds and hail. A Severe Thunderstorm Watch is in
  effect for south central to southeast WI until 8 PM CDT
  tonight.

- Dangerous swim conditions continue this afternoon and evening
  for east central WI beaches due to high waves and onshore
  winds.

- Poor air quality is expected through the evening for our
  lakeshore counties.

- Hot and humid conditions expected for the start of the week with
  temps and heat indices in the 90s. Hottest temps and heat
  indices are likely during the day Monday.

- There will be daily thunderstorm chances through the week due
  to the warm and humid conditions.
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&&

.SHORT TERM...
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Issued 344 PM CDT Sun Jun 16 2024

Tonight through Monday night:

Main concern or this afternoon and evening is the strong to severe
thunderstorm potential as the MCV across eastern IA/northwestern IL
tracks northeast. While the ongoing convection is undercut by
the outflow racing ahead of it, thinking there will be
redevelopment ahead of it as the outflow loses it steams as it
pushes into south- central WI. Redevelopment looks to fueled by
the environment which has destabilized with SBCAPE north of
2000 J/kg and effective bulk shear around 25-30 knots. If any
storms can get going and grow upscale, the environment is
supportive of damaging winds threat along with a hail threat. In
addition to the outflow boundary, can see hints of an effective
warm front boundary on MKX radar strewn across southern WI
along with a stalled lake breeze near the lakeshore in
Racine/Kenosha counties. Thus, severe thunderstorm or two will
be possible through the evening as this activity pulls through
the area this evening with the main concern being damaging
winds. However, if any storms do interact with any of these
boundaries, cannot rule out a brief spin up if things align just
right. The main area of concern to see strong to severe storms
will be along the WI/IL border north along the I-94/HWY-18
corridor. Potential should decrease through the evening.

Could see additional shower and thunderstorm chances glance our
northern CWA overnight as the upstream convection develops and
pushes eastward ahead of the mid-level shortwave trough.  Less
confident on seeing this activity make it into our area, but the
potential still remains.

Life threatening waves and currents continue resulting in high
swim risk through this evening for Lake Michigan beaches in
Sheboygan and Ozaukee counties, while moderate swim risk remains
in place for Milwaukee, Racine and Kenosha counties. Conditions
should improve overnight as waves and winds subside a bit.

Otherwise, looking to continue with the hotter and humid conditions
for Monday as we sit under the western peripheral of the upper-level
ridge. Looking at daytime temps in the upper 80s and 90s and even
hotter heat indices in the mid to upper 90s. While we will near heat
advisory levels, think we will generally remain below threshold
at this time, but still need to exercise caution if outdoors or
exposed to the heat. Overnight temps are looking very warm as
well with lows only dipping into the lower 70s.

Additionally cannot rule out a few pop-up isolated showers/
thunderstorms for Monday afternoon. While there is not a real
discernible forcing mechanism to trigger the storms at this
time, cannot ignore the ample moisture (dewpoints in the
60s/70s) and instability (SBCAPE +20000 J/kg) available. The
main forcing mechanism that could potential trigger a storm or
two would likely be from a lingering boundary from overnight
convection tracking across the area, but difficult to tell if
and where this may occur.

Wagner
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&&

.LONG TERM...
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Issued 344 PM CDT Sun Jun 16 2024

Tuesday through Sunday:

Heat and humid conditions will continue Tuesday into Wednesday with
daily low-end shower/storm chances. A cold frontal boundary looks to
gradually push southward through WI during the day Wednesday into
Thursday, which will be enough forcing along with a right entrance
region of an upper-level jet for the increased shower/thunderstorm
chances. The frontal boundary is trending on stalling across the
area through the end of the week bringing additional precipitation
and storm chances.

Wagner
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&&

.AVIATION...
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Issued 344 PM CDT Sun Jun 16 2024

Warm, humid and gusty conditions with south to southwesterly winds
gusting to 20-35 knots will continue through the evening. Potential
to see additional thunderstorm development through the evening
continues to increase, especially for JVL and ENW, but cannot rule
out seeing some of the activity creep as far northeast as UES
and MKE. With this activity cannot rule out a strong to severe
thunderstorm or two, which can bring heavy rainfall, hail, and
localized gusty winds shift along with a brief hour or two
period of lower flight conditions. The potential decreases after
02z and otherwise, mostly VFR and gusty winds should prevail
through the period.

Wagner
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&&

.MARINE...
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Issued 344 PM CDT Sun Jun 16 2024

Watching a complex of thunderstorms across eastern IA as
they push east-northeast toward Lake Michigan. This complex of
storms can bring strong to severe winds and a sudden wind shift with
it. It will move through southern half of Lake Michigan this evening
with decreasing chances overnight. Otherwise, will continue to see
south winds with gusts around 25-30 knots through the afternoon as
low pressure over southern Manitoba approaches the region and high
pressure sits over New England. Another area of low pressure will
approach from the Plains on Monday and Tuesday. Breezy south winds
will continue over Lake Michigan with gusts approaching 30 knots. A
cold front will then slowly move southward across the lake either
Wednesday or Thursday and stall into Friday.

Wagner
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&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Beach Hazards Statement...WIZ052-WIZ060 until 1 AM Monday.

LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 1 AM
     Monday.

&&

$$

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