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000
FXUS63 KMKX 060830
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
330 AM CDT Thu May 6 2021

.SHORT TERM...
(Issued 330 AM CDT Thu May 6 2021)

Today through Friday:

Rain expected to continue this morning as the UL shortwave pushes
through the region. Deep moisture as well as an abundance of
forcing from the upper levels with the shortwave to the low to mid
levels with WAA and plenty of Fgen. This should push out by the
late morning. However, we may see continuing isolated to scattered rain
showers through the afternoon, particularly near the lake, as a
result of some lake breeze surface wind convergence, WAA and
corresponding near surface Fgen. Some of these showers may be in
part forced by the surface trough, especially any more inland
showers. Several of the CAMs suggest potential for these isolated
showers persisting into the late afternoon before another feature
may bring some additional showers in the early evening. This is
shown in the CAMs as well as a few models likely forced by some UL
PVA from the incoming shortwave as well as potentially some WAA
and maybe even some weak surface convergence that appears somewhat
diurnally driven.

There will likely then be a break in the chances for precip for a
few hours in the evening but into the overnight period we will
see that UL shortwave come through the region likely bringing
scattered rain showers. This wave will quickly push through and
will likely be out of the region by just after sunrise. Then we
will again see some daytime lake breeze surface convergence with
plenty of near surface Fgen. This is expected to again provide
some scattered showers near the lake. Overall much of the next few
days will feature chances for rain though not much in the way of
rainfall amounts is expected.

Kuroski

&&

.LONG TERM...
(Issued 330 AM CDT Thu May 6 2021)

Friday night through Thursday:

With surface high pressure and a very dry airmass overhead Friday
night into Saturday morning, widespread frost looks likely as low
temperatures fall to 32 to 35 degrees. This is towards the low
end of guidance, but the expected conditions and pattern certainly
support going this low. Saturday we will see a sunny start to the
morning, with increasing diurnally driven cloud cover as mixing
deepens. Winds will remain light throughout the day as high
pressure tracks across the region, variable Saturday morning then
becoming east-southeast during the afternoon and evening hours.
Highs will top out near 60 across the south-central, while
easterly flow and the lake breeze pushing inland from Lake
Michigan will keep highs in the 50s across east-central and
southeast Wisconsin.

Saturday night through Sunday night, a low pressure system
developing in the lee of the Rockies will track east across the Ohio
River Valley. Deterministic model guidance continues to keep the
bulk of precipitation with this system just off to our south, across
northern Illinois, outside of the 00z GFS which did trend a bit
further north. Members within the EPS and GEFS do support some light
precipitation making it up into southern Wisconsin. Thus, did leave
some PoPs in for late Saturday night through Sunday, focused closer
to the WI/IL border where deterministic and ensemble guidance have
the best combined support at this time. Northeast to north winds
should be on the breezy side as the pressure gradient across the
region increases north of the main surface low.

Next week, high pressure sinks south across the Great Lakes from
the Canadian Prairies. This will bring a stretch of drier weather
and a gradual warm up as a warmer, modified airmass moves into the
region.

Anderson

&&

.AVIATION...
(Issued 330 AM CDT Thu May 6 2021)

Rain continues this morning and is expected to push out by later
this morning. Meanwhile, CIGS will drop as this system moves
through with mostly MVFR CIGS expected, possibly even IFR for a
time based on models and upstream conditions. CIGS will improve
this morning into the early afternoon. May see a few afternoon
showers particularly closer to the lake as the lake breeze may
trigger some showers. In addition we could see some early evening
showers in some areas and then more scattered showers overnight
into Friday morning. Friday afternoon may again feature another
period of lake breeze induced showers.

Kuroski

&&

.MARINE...
(Issued 330 AM CDT Thu May 6 2021)

A weak low of 30.1 inches slides south of the lake today, followed
by another weak trough of 29.9 inches pushing west to east across
the western Great Lakes Friday morning. Behind this second trough,
the pressure gradient builds over Lake Michigan during the day on
Friday, as a 30.2 inch area of high pressure begins to drop south
into the upper Great Lakes. High pressure hangs around Friday night
through Saturday. Saturday night into Monday, low pressure of 29.4
inches in the central Plains tracks east across the Ohio River
Valley and weakens slightly. As the system grazes Lake Michigan to
the south, it does appear we will see stronger NE to N winds over
the southern half of Lake Michigan late Sunday into Monday. Gales
don`t look likely at this time, but NE to N winds of 20-30kt do look
possible over the southern half. If these stronger winds hold up,
the combination of winds and building waves could bring back small
craft conditions.

Anderson

&&

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

$$

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