Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI

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FXUS63 KMKX 181719
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1119 AM CST Sun Nov 18 2018

.UPDATE...

No significant changes anticipated through the afternoon.

&&

.AVIATION(18Z TAFS)...

Light west to southwest winds will prevail through the next 24
hours. Skies will generally be clear this afternoon, with some
high clouds building in late tonight. A cold front will approach
tomorrow afternoon, with lower clouds expected behind that front.
However, this should occur after 18Z tomorrow.

&&

.MARINE...

Open Waters...Winds will become westerly over the lake this
morning, with some gusts to around 30 knots expected over the
north half of the open waters. Further south, expect gusts to
around 20 knots.

Winds will become northerly tomorrow evening, with gusts 25-30
knots expected overnight. An area of higher waves to 8 feet is
expected to move from north to south along the lake in response.

Winds will then increase from the south to southwest Tuesday into
Wednesday, with gale force gusts possible over the open waters.

Nearshore...Quiet conditions are expected today, with waves
increase tomorrow afternoon and evening. A Small Craft Advisory
may be needed for this time.

PREV DISCUSSION... (Issued 250 AM CST Sun Nov 18 2018)

DISCUSSION...

Today and tonight...Forecast confidence is high:

High pressure will bring a quiet day to southern Wisconsin today.
Skies have begun to clear from the northwest and will continue to
do so through the early morning. Sunny skies are thus expected for
the majority of the upcoming day. Despite plenty of sun, temps
will remain below normal due to the chilly airmass in place.

Mid and high level clouds will increase tonight, which should put
a damper on radiational cooling later in the night. Below normal
low temps in the low 20s are still expected though.

Monday and Monday night...Forecast confidence is high.

Surface low pressure will track from northern WI to northern
Lower Michigan on Monday. A trailing cold front will sweep across
the area during the afternoon...bringing yet another reinforcing
shot of colder air to the area. Most of the associated weather
will stay to the north...across central and northern Wisconsin.
But, can`t completely rule out some light snow with the frontal
passage, so will maintain the small chcs we`ve had going. No
accumulation is expected. Cold high pressure builds in for Monday
night. However, winds turn north to possibly northeast near Lake
Michigan Monday night and this could allow some lake effect snow
showers to clip our far southeast later Monday night. The bulk of
that snow should be an Indiana/Illinois problem.

Tuesday and Tuesday night...Forecast confidence is high.

After a cold start with a high pressure ridge overhead in the
morning, low pressure will track just north of Lake Superior while
the ridge pushes south. This eventually puts us in a southwest
return flow with decent h8 warm air advection in the afternoon. We
won`t really benefit much at the surface as the warm air remains
mostly elevated into Tuesday night. A cold front trailing the low
will push south into the area by Wednesday morning, but it will
be washing out due to the persistent elevated WAA it`s pushing
into. At this point, any associated weather should stay well north
of the forecast area.

Wednesday through Thursday night...Forecast confidence is high.

The upper level pattern begins evolve from a cold northwest flow
to a zonal one by Wednesday night, eventually going southwest
Thursday night. This signals the start to a noticeably milder, more
normal trend in temperatures later in the week. This period looks
dry under high pressure. Temperatures will also be a bit milder,
but still a few degrees below normal.

Friday through Sunday...Forecast confidence is medium.

A southerly flow will pull a warmer and more moist air mass north
into the region. A low pressure trough approaching from the west
pushes in very slowly late in the week. The Canadian/GFS/ECMWF are
handling a complex mid level trough evolution somewhat differently
resulting in varied timing/pressure pattern details at the
surface. For now, it will have to suffice to generalize as a
milder period with chance of precip from time to time. Given the
thermal profile, rain looks to be the dominant precip type.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...None.
&&

$$

Update...Boxell
Today/Tonight and Aviation/Marine...Boxell
Monday THROUGH Saturday...99



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