NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 051512 AAA
AFDMKX

Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
912 AM CST Wed Nov 5 2025

.KEY MESSAGES...

- A period of light rain (55-75% chance) will lift through
  southern Wisconsin Thursday night into Friday morning.

- Additional precip chances (~40-65%) arrive Saturday afternoon through
  Sunday morning, with snow and rain/snow mix possible. Minor &
  slushy accumulation can't be ruled out, especially on grassy
  surfaces.

- First winter-like air of the season arrives late this weekend
  into early next week, with temperatures 10 to 15 degrees below
  normal in spots.

&&

.UPDATE...
Issued 912 AM CST Wed Nov 5 2025

Breezy northwest winds are expected behind a cold front today
along with decreasing clouds. The forecast looks on track
through the afternoon hours with no significant updates
anticipated.

DDV

&&

.SHORT TERM...
Issued 315 AM CST Tue Nov 4 2025

Today through Thursday:

Low pressure continues to push through the central Great Lakes
region this morning with the front likely getting through
southern WI over the next few hours bringing breezy northwest
winds behind it and mostly clear skies by the late morning/
early afternoon. Given the unstable conditions given the CAA
behind this system decent mixing is to be expected and thus
gusty northwest winds to 30mph with be possible with some modest
LLJ winds. This will also allow for temps to reach the mid to
upper 50s despite the stronger CAA from Canada. The overall
cooler conditions will moderate RH values and prevent the low
end outcomes and prevent fire weather concerns for the most
part.

As the low pushes out today, high pressure will build into the
region weakening winds and allowing for clear skies to continue
but also for cooler overnight temperatures. This high pressure
will quickly exit the region to the east but will remain the
dominant feature over the course of the day Thursday, with
perhaps some upper clouds building late in the afternoon as
another system approaches from the west.

Kuroski

&&

.LONG TERM...
Issued 315 AM CST Tue Nov 4 2025

Thursday night through Friday:

Into Thursday evening winds will increase from the south as
precip chances increase as well, as the low to mid levels
moisten up with strong LLJ and WAA. The signals for PVA in the
upper levels continue to be modest but are more favorable that
previous models runs, but the focus for ascent continues to be
in large part drive by midlevel WAA/LLJ.

Now there continue to be some failure points with this system
but generally models have come more in line on the solutions.
There remains some phasing concerns, especially as that relates
to when moisture gets into this system in the low to mid levels.
The concerns for the westerly extent of precip seems to now be
justified with a downward trend in pops for western parts of the
CWA. This primarily due to the later influx of moisture into the
system or that the system is moving slightly quicker. In either
case western parts of the CWA continue to see a downward trend
on precip chances (40-60%), which may actually continue to
decline further. However, central and eastern parts of the CWA
continue to see much better chances as models have come into
better agreement on the where and when to expect the influx of
moisture. The most likely outcome looks to be that showers
develop in the western to central portions of the CWA and as
moisture and forcing increase with the LLJ moving directly
overhead we will see showers become more widespread. It should
however be noted that because moisture depth is still not
profound in any way that its not expected to be a washout with
QPF very likely remaining well under 0.25 in for most if not all
of the CWA. Highest rainfall will very likely be seen on the
eastern parts of the CWA. This system will push out Friday
morning as the surface low pushes out toward the far easter
Great Lakes region. We cannot rule out a brief shower on the
backend of this system late Friday/Friday night, but it
currently remains unlikely (10-15%). Otherwise expect breezy
northwest winds behind the low Friday.

Kuroski

Friday Night through Tuesday:

Synopsis: Behind the departing Thursday-Friday system, northwest
surface winds, will begin to pull cooler air into the western Great
Lakes Friday night, resulting in chillier overnight lows and high
temperatures during the day on Saturday. Dry weather will hang on
through early Saturday morning. Conditions will change during the
afternoon and evening hours, when a compact upper shortwave will
drive into the western Great Lakes and Ohio River Valley from the
Northern Plains. The arriving wave will encourage surface
cyclogenesis in the vicinity of the Iowa-Missouri border during the
afternoon hours, with further deepening anticipated to the south and
east of the region Saturday night. Lift the shortwave, in addition
to sharpening frontogenesis along/north of the developing surface
low, will thus result in returning precipitation chances Saturday
afternoon through early Sunday morning. Evening/overnight timing of
precipitation, in addition to the cooler air mass already in place.
Snow and rain/snow mix continue to be a possibility given overnight
timing and the cooler air already in place. Minor, slushy
accumulation can't be completely ruled out, particularly on grassy
surfaces. Precip potential will trend down by Sunday afternoon as
lift moves east of the region. Renewed northwesterly surface winds
will pull the first Winter-like air mass of the season into southern
Wisconsin Sunday afternoon into the beginning of next week.

Saturday through Sunday Morning: Precip chances return areawide
ahead of the next disturbance. Have maintained NBM precip
probabilities in the overnight forecast, which depict broad 40-65%
values across most of southern Wisconsin. Given a heavy
frontogenetic component to forcing in this system, do anticipate
that PoP gradients will begin to tighten up (and potentially
increase further in spots) as the system approaches & forecast
guidance settles on the locations of peak frontogenesis. As
mentioned in the synopsis, snow and rain/snow mix will be a
possibility, with some potential for minor/slushy accumulation.
Probabilistic guidance shows low to medium (~20-50%) chances for a
trace or more, with current values for anything greater than an inch
much lower. Expect that any minor accumulation would focus on grassy
surfaces, with road temperatures still above freezing across much of
the area. Will continue to monitor trends, particularly as mesoscale
model guidance starts coming into range over the next 24 hours.

Sunday Afternoon through Tuesday: The season's first batch of Winter
air will settle into the region behind departing low pressure.
Northwesterly surface winds will contribute to sustained cold
advection through Monday night, resulting in well below normal
temperatures (~10-15 degrees). Current NBM guidance suggests that
highs could struggle to reach 40 degrees Sunday/Monday, with
widespread lows in the lower 20s Sunday night and Monday night.
Scattered overnight lows in the teens are possible, particularly
away from Lake Michigan.

Quigley

&&

.AVIATION...
Issued 912 AM CST Wed Nov 5 2025

Breezy northwest winds are expected behind a cold front today
along with decreasing clouds as high pressure builds in from the
west. Winds will ease this evening into tonight as the high
moves overhead, with mostly clear skies likely. Breezy southerly
winds will develop on Thursday as high pressure moves on to the
east ahead of an approaching low. Mid to high level clouds will
increase tomorrow ahead of the low.

DDV

&&

.MARINE...
Issued 315 AM CST Tue Nov 4 2025

Winds will turn to northwesterly behind a low pressure system
and associated cold front this morning. Winds will approach gale
force later this morning through this afternoon until the
pressure gradient weakens and the low moves into the New England
states. Small Craft Advisory remains in effect through 9PM CST
tonight for breezy northwest winds.

This evening winds will diminish and become light as high
pressure moves from the Northern Plains into the Ohio River
Valley. Light northwest winds will turn to southerly Thursday.
Winds will increase again as the pressure gradient tightens ahead
of an incoming low pressure Thursday night. There is a
potential for some southerly gales during this time. This low
will cross northern Minnesota and move over Lake Superior
dragging a cold front across Lake Michigan. Behind the front
Friday morning, brisk northwest winds are expected. These brisk
winds will persist through Monday. Expect additional periods of
Small Craft conditions from Thursday afternoon through the
weekend.

Kuroski

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 9 PM
     Wednesday.

&&

$$

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