Dense Fog in Wisconsin, September 30, 2021

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
404 AM CDT Thu Sep 30 2021

.SHORT TERM...
(Issued 310 AM CDT Thu Sep 30 2021)

Today through Friday Night:

Fog continues this morning given calm winds and strong high
pressure overhead making for good enough conditions for fog
despite upper level clouds. Fog has mostly remained to the east
and seems to be denser to the northeast and much shallower
elsewhere. Thus we have a Dense Fog Advisory in effect until 14z
for Fond du Lac, Sheboygan, Washington and Ozaukee counties with
areas to the south seeing pockets of dense fog.

Into the day today we should expect the sun to help the fog
dissipate within a few hours after sunrise. The rest of the day
looks to remain fairly quiet with the strong surface and upper
level ridge dominating the region and keeping the CWA dry.

Into tonight we expect the upper level ridge to begin breaking
down with the surface high slowly pushing east. However recent
trends in the models suggest the surface high may stick around a
bit longer with the upper level ridge breaking down but remaining
strong enough to keep forcing associated with the shortwave to
the west and out of the area at least through much of the day
Friday and possibly through Friday night as well. Friday night it
appears as though better chances for precipitation will begin to
sneak into the western parts of the CWA but much of the region
should still remain dry.

Kuroski

&&

.LONG TERM...
(Issued 400 AM CDT Thu Sep 30 2021)

Saturday through Wednesday:

A weak sfc low will move from the nrn Great Lakes to the lower
Great Lakes for the weekend. Its cold front will slowly pass Sat
nt possibly lingering into Sun AM over far se WI. A moist flow
ahead of the low will increase PWs to 1.5 inches with tall, skinny
CAPE present on fcst soundings. Various weak vorticity maximums
will affect the area during this time. Thus, scattered showers
and storms are expected for the weekend, and could become more
widespread especially over far srn WI for Sat nt-Sun. Above normal
temps will continue into Sat with humid conditions. Nly winds in
the wake of the cold front will cool temps back to normal for Sun
and beyond. High pressure will then build into the nrn Great Lakes
later on Mon and expand into Tue-Wed. Lgt enely winds and
pleasant autumn conditions are fcst.

Gehring

&&

.AVIATION...
(Issued 310 AM CDT Thu Sep 30 2021)

VLIFR VSBYS due to fog continue across the eastern parts of
southern Wisconsin and will likely continue through the early
morning hours before the sun helps to dissipate the fog. It's
important to note that fog is certainly more dense to the north
and east whereas further south it appears to be shallower and
less widespread. Otherwise CIGS related to fog remain very low as
well but generally once the sun comes up fog will clear out
bringing VFR conditions the rest of the day with light southeast
winds. Fog is less likely tonight given the increase in winds.

Kuroski

&&

.MARINE...
(Issued 310 CDT Thu Sep 30 2021)

High pressure of will remain over the Great Lakes through Friday
pushing slowly east, lingering a bit longer than originally
expected. This will keep lighter winds across the lake though we
will still see modest increases as winds turn more southerly for
Friday. This will also keep chance for precip to the west for a
longer period of time. By Saturday the low pressure system should
push in bringing chances for precip through Sunday. The low will
likely deepen as it pushes through potentially bringing some
breezy northerly winds behind the system for Monday.

Kuroski

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Dense Fog Advisory...WIZ051-WIZ052-WIZ059-WIZ060-WIZ065-WIZ066
     until 9 AM Thursday.

LM...None.
&&

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Hazardous Weather Outlook
National Weather Service Milwaukee/Sullivan WI
318 AM CDT Thu Sep 30 2021

WIZ046-047-051-052-056>060-062>072-010830-
Marquette-Green Lake-Fond du Lac-Sheboygan-Sauk-Columbia-Dodge-
Washington-Ozaukee-Iowa-Dane-Jefferson-Waukesha-Milwaukee-
Lafayette-Green-Rock-Walworth-Racine-Kenosha-
318 AM CDT Thu Sep 30 2021

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

.DAY ONE...Today and Tonight

Dense fog continues across portions of east-central Wisconsin
where a Dense Fog Advisory is in effect. The Dense Fog Advisory
has been expanded a bit further south and still may need
additional expansion southward.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

There are small chances for thunderstorms Saturday and Saturday
night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

LMZ643>646-010830-
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-
318 AM CDT Thu Sep 30 2021

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

.DAY ONE...Today and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

There are small chances for thunderstorms Saturday and Saturday
night.

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-010830-
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-
318 AM CDT Thu Sep 30 2021

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

.DAY ONE...Today and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

There are small chances for thunderstorms Saturday and Saturday
night.

www.weather.gov/mkx