Wilmot Mountain

000
FXUS63 KMKX 312353
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
653 PM CDT Sat Oct 31 2026

.KEY MESSAGES...
 
- Predominantly dry weather tonight through Sunday night; an
  isolated sprinkle of rain possible at times. 

- Unsettled weather pattern will impact the area Monday through Wednesday,
  bringing widespread rainfall and a few thunderstorms. 

- Unsettled weather may continue into the end of the week before
  dry conditions take hold next weekend.

&&

.UPDATE...
Issued 650 PM CDT Sat Oct 31 2026

Sprinkles of rain have largely ended for the rest of the evening
and tonight, some isolated feint radar echoes are all that
remain over portions of eastern and east-central WI. A decaying
patch of showers over west-central IL moving northeastward could
deliver some additional sprinkles or even light rain showers
late tonight (after Midnight), mainly for areas near the WI/IL
border. No thunder expected with this activity.

Similarly, an isolated sprinkle cannot be ruled out on Sunday,
though forcing for ascent is insufficient for much else. Should
be predominantly dry through the rest of the weekend. 

Sheppard

&&

.SHORT TERM...
Issued 205 PM CDT Sat Oct 31 2026

This Afternoon through Sunday Night: 

Synopsis/Mesoanalysis: High pressure is centered near Lake Erie this 
afternoon, resulting in generally southeast winds across southern 
Wisconsin. A weak area of low pressure is centered over northeast 
Wyoming, with a diffuse warm front extending east-southeast from the 
low through South Dakota into southwest Wisconsin. Surface 
temperatures differences are ill-defined across the Wisconsin 
segment of the boundary, though residual warm advection and 
frontogenesis near 925 mb have provided sufficient forcing for rain 
currently extending from Platteville toward Janesville. Expect this 
activity to attempt to work northeast through the remainder of the 
afternoon and into the first half of the evening. Currently centered 
over the Kansas City vicinity, shortwave troughing will shift toward 
southern Lake Michigan tonight. Affiliated lift from the wave may 
trigger an isolated shower or sprinkle in far southeast Wisconsin, 
with other locations staying dry. Aforementioned areas of surface 
high and low pressure will linger over the same vicinities on 
Sunday, with sunnier skies allowing for warmer high temperatures in 
the presence of southeasterly surface flow. 

Rest Of This Afternoon: Anticipating that rain currently ongoing 
from Janesville to Platteville will continue to migrate northeast 
along a band of 925 mb warm advection and frontogenesis. Despite 
larger dew point depressions in the near-surface layer regionally, 
forcing within the WAA-FGEN band has provided sufficient lift to 
overcome evaporation/produce a brief period of rain. Have adjusted 
near-term precip probs to account for expectations. Accumulations 
will remain light (~0.1" or less), with an absence of instability 
pointing toward minimal thunder/lightning potential.

Quigley

&&

.LONG TERM...
Issued 205 PM CDT Sat Oct 31 2026

Monday through Saturday:

Synopsis: A elongated area of upper troughing will progress into 
central portions of the continent Monday through the middle of the 
week, slowly dragging an attendant surface front eastward in the 
process. The trough and surface front will pull close enough to 
influence southern Wisconsin's weather Monday afternoon into at 
least Tuesday night, when widespread rain and a few thunderstorms 
are possible. Precise pattern evolution becomes considerably more 
uncertain from mid-week onward, with a multitude of potential 
solutions regarding the progression & fate of the early week trough 
and surface front in-play. With some potential for one or both of 
the features to linger in the vicinity of southern Wisconsin, 
conditional periods of rain chances continue through the end of next 
week. Temperatures are expected to remain either at or above early 
November normals through the duration of the period.  

Monday afternoon through Tuesday: The most confident window of the 
long term forecast period opens as a coupling of low & mid-upper 
synoptic forcing arrive into the area, driving widespread rain 
potential. Expecting precip to begin Monday afternoon & evening as 
large scale warm advection increases regionally, with rain potential 
extending into Tuesday as the primary surface front & upper wave 
encroach from the west. Available medium-range forecast soundings 
hint at some weak MUCAPE through this portion of the period, so 
can't entirely rule out a few thunderstorms mixing in with the 
widespread rainfall. Tend to think that projected MUCAPE values will 
be too meager to support any stronger thunderstorms, but will be 
monitoring trends. Presence of embedded convection within an 
environment characterized by 1.3"+ precipitable water values could, 
however, lead to some brief heavy downpours in storms. Not 
anticipating a widespread flooding threat at this time given the 
isolated & brief nature of any such downpours. Initial probabilities 
from the NBM point toward 0.25-0.50" rainfall totals areawide, with 
the potential for locally higher totals to 0.75"+ where any heavier 
downpours focus.  

Wednesday-Friday: Off/on, conditional rain chances remain forecast 
with some potential for the early week surface front and/or upper 
trough to linger regionally. Whether one/both of these features 
actually do linger will depend on 1) the phasing of northern and 
southern perturbations embedded within the broader area of longwave 
troughing and 2) the subsequent impacts on the strength of the 
surface front. If upper phasing occurs, height falls will linger 
over the western Great Lakes through the end of the week, combining 
with the remains of the surface front to support continued off/on 
rain chances. If phasing doesn't occur, a tendency toward height 
rises will become favored, combining with a decaying surface front 
to support drier conditions. Neither deterministic nor ensemble-
based guidance point toward a favored solution at the moment, with 
trends being monitored for convergence over coming updates. Given 
the prevailing uncertainty, have maintained precip probabilities 
from the NBM in the afternoon update & will plan to refine as this 
portion of the period draws closer. 

Quigley

&&

.AVIATION...
Issued 650 PM CDT Sat Oct 31 2026

Predominantly dry and VFR conditions expected through the TAF
period, with light south to southeast winds and overcast to
broken cloud cover creating VFR ceilings (around 7,000 ft AGL on
average, generally no lower than 4,000 ft). Some isolated
sprinkles of rain and/or patches of MVFR ceilings are possible
at times. Best shot at a stray rain shower would be near the 
WI/IL border late tonight (after Midnight) through predawn
Sunday morning. 

Sheppard

&&

.MARINE...
Issued 205 PM CDT Sat Oct 31 2026

1032 mb high pressure is centered near Lake Erie this afternoon, 
resulting in generally east to southeast winds across the open 
waters of Lake Michigan. The high will drift southeast into the 
northeastern United States through Sunday, allowing winds to trend 
southerly across the lake. Low pressure near 1000 mb will develop 
over eastern Colorado Sunday evening, progressing into the Upper 
Mississippi River Valley into early Tuesday morning. Winds will 
steadily become gusty ahead of the approaching low, approaching or 
exceeding gale force over at least the central third of the lake 
Tuesday afternoon and evening. Anticipate that headlines will become 
necessary in later forecasts. 

Winds will remain breezy, though likely below gale levels Wednesday 
and Wednesday night as 1020 mb high pressure slowly builds into the 
Canadian Great Plains. Said high will move into the western Great 
Lakes through the second half of next week, allowing for westerly 
and eventually north winds by next weekend. 

A brief period of elevated waves continues through this afternoon in 
nearshore zones, with a Small Craft Advisory in effect through 10 PM 
CDT from North Point Light to Sheboygan. A prolonged period of gusty 
winds and elevated wave heights is then anticipated from Monday 
through at least Wednesday morning, with a combination of Small 
Craft Advisories and Gale Warnings becoming necessary in later 
forecasts. Most likely period for gales will be Tuesday afternoon & 
evening, with Small Craft Advisory conditions anticipated in the 
lead up to and following the gale time frame. Conditions will 
improve Wednesday night into Thursday.

Quigley

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory...LMZ643-LMZ644 until 10 PM Saturday.

&&

$$

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