NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 181914
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
214 PM CDT Sat Jul 18 2026

.KEY MESSAGES...

- The Wisconsin DNR has issued an Air Quality Advisory for all
  of Wisconsin into Monday morning, as wildfire smoke moves
  southward into the area tonight and lingers, contributing to
  lower visibilities and unhealthy air quality.

- High Swim Risk conditions are expected at southern Wisconsin
  beaches in Ozaukee County and southward tonight into early
  Sunday morning.

- Severe storms are possible mainly Monday afternoon and
  evening. All severe hazards are possible during this time.
  There is some uncertainty with a possible first round of
  storms may affect the airmass recovery for a potential second
  round.

&&

.SHORT TERM...
Issued 214 PM CDT Sat Jul 18 2026

Tonight through Monday Morning:

The cold front has moved south of the area, and any showers and
storms will remain in that area into this evening. Thus, dry
conditions are expected for the area into tonight. High
pressure moving slowly southeast through the region Sunday into
Sunday night will continue to bring dry conditions to the area.

The Wisconsin DNR has issued an Air Quality Advisory for all of
Wisconsin into Monday morning. Most of the near-surface smoke
models are bringing more wildfire smoke south/southwest into the
area later this afternoon into this evening, overspreading the
area overnight into Sunday morning. They start to differ with
how much smoke may linger Sunday afternoon into Sunday
night/Monday morning, with some mixing out areas over and near
Lake Michigan. For now, will generally keep areas of smoke in
the forecast tonight into Monday morning, until a more robust
signal for the smoke to move out or dissipate occurs.

The Wisconsin DNR is indicating air quality in the Unhealthy
for All Groups impact level. In addition, visibility may be
reduced to 2 to 5 miles at times, with the more concentrated
visibility reductions tonight into Sunday morning.

Temperatures and dew points should lower somewhat tonight into
Sunday night, with the high moving through the region. Lows in
the lower to middle 60s are anticipated tonight and Sunday
night, with highs Sunday in the lower to middle 80s, warmest
inland from Lake Michigan with onshore winds developing. Given
the lower dew points, heat index values will be similar to air
temperatures Sunday.

High Swim Risk conditions are expected tonight into early
Sunday morning for the Lake Michigan beaches from Ozaukee County
southward through Kenosha County. A Beach Hazards Statement is
in effect for these areas. Waves should reach to around or above
4 feet in this area, with values below 4 feet for Sheboygan
County beaches. A Moderate Swim Risk is expected there.

Wood

&&

.LONG TERM...
Issued 214 PM CDT Sat Jul 18 2026

Monday Afternoon through Saturday:

Severe storms are possible mainly Monday afternoon and evening,
with the area in a Slight Risk for severe storms from SPC.
There should be robust instability with mean layer CAPE over
2000 J/kg and strong deep layer bulk shear of 40 to 50 knots or
greater. A strong cold front should push east across the region
as well Monday evening and overnight, though may be more
overnight as it moves through the area. A 500 mb vorticity
maximum shifting southeast through the region later Monday night
may occur, with a northwesterly jet streak building into the
area.

There may be two rounds of storms, and the first round may
dictate how much activity occurs with the second. Models seem to
develop an MCS over northwest and west central Minnesota Sunday
night and shifts is southeast Monday morning into northeast
Iowa, southeast Minnesota or far southwest Wisconsin. This
feature seems to be driven by focused warm air advection at 850
mb and low level frontogenesis. This may or may not weaken
during the morning into the afternoon, and it presence may limit
airmass recovery for the second round of convection with the
cold front Monday evening/night. It may also tap into the
building instability and shear and strengthen if it can clip
southwest parts of the area.

Will see how this evolves over the next day and hopefully will
have a better idea of what may occur. Given the amount of
instability and shear, severe storms will all hazards are
possible. If the second round of storms develops, a line with
bowing segments and perhaps QLCS features may occur.

For the rest of the week, northwest flow aloft should linger
across the region. Gusty northwest winds Tuesday may bring in
some drier air and more pleasant temperatures, with lighter
winds Wednesday as high pressure moves through. Things may get
more active by the end of the week, with warmer and more humid
air moving back into the region.

Wood

&&

.AVIATION...
Issued 214 PM CDT Sat Jul 18 2026

The cold front has moved south of the area, and any showers and
storms will remain in that area into this evening. Scattered to
sometimes broken cumulus around 3500 to 4500 feet AGL are
expected into this evening, as gusty winds veer northeast into
this evening.

Dry conditions are expected for the area into tonight. High
pressure moving slowly southeast through the region Sunday into
Sunday night will continue to bring dry conditions to the area.

More wildfire smoke is expected to move south/southwest into
the area later this afternoon into this evening, overspreading
the rest of the area overnight into Sunday morning. There is
some uncertainty with how much smoke may linger Sunday
afternoon into Sunday night/Monday morning. For now, will
generally keep smoke with 2 to 5 mile visibility at the
terminals tonight into Sunday. Some uncertainty if any vertical
visibility restrictions will develop as well.

Light and variable winds overnight should become east to
southeast on Sunday for terminals near Lake Michigan, and more
south to southeast further inland.

Wood

&&

.MARINE...
Issued 214 PM CDT Sat Jul 18 2026

Wildfire smoke will return to Lake Michigan into tonight and
may become dense once again. The smoke is expected to reduce
visibility to 1 nautical mile at times, and a Marine Dense Smoke
Advisory is in effect across Lake Michigan into early Monday
morning.

Gusty northwest winds will veer north to northeast behind the
front into this evening. Winds then quickly taper off tonight,
as high pressure around 30.1 inches moves over the northern
Great Lakes. Northeast to light and variable winds are then
expected Sunday into Sunday night. Gusty south to southwest
winds may then develop Monday into Monday night, with gusty west
to northwest winds possible into the middle of next week.

For the nearshore waters, a Small Craft Advisory is in effect
tonight into early Sunday morning, mainly for building waves of
3 to 5 feet. The winds and waves should then subside, as the
high moves into the region. Winds and waves may reach Small
Craft Advisory levels at times Monday into Wednesday.

For the open waters, a few southerly gales are possible Monday
afternoon and evening, with a few northwest gales possible
Tuesday night into Wednesday.

Wood

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Beach Hazards Statement...WIZ060-WIZ066-WIZ071-WIZ072...7 PM
     Saturday to 7 AM Sunday.

LM...Small Craft Advisory...LMZ643...7 PM Saturday to 2 AM Sunday.

     Small Craft Advisory...LMZ644-LMZ645-LMZ646...7 PM Saturday to
     7 AM Sunday.

&&

$$

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