textproduct: Milwaukee/Sullivan

KEY MESSAGES

- Rain is overspreads the region in a south to north fashion Thursday afternoon, peaking in intensity from 3 PM to 9 PM, then likely featuring a lull this evening/night. Cannot rule out some thunder this evening.

- The mild temperatures and rain today into Friday will allow for ice to break up along rivers, with potential for ice jams. Isolated minor river flooding and ponding of water in poor drainage areas will also be possible as the rain falls on partially frozen soil.

- Roughly 60 percent chances for light precip to continue into Friday. Some snow may briefly mix in, but will not accumulate. - Accumulating snow is looking likely (60 to 80 percent chances) Saturday for our region. Uncertainty remains quite high at this time.

UPDATE

Issued 1030 AM CST Thu Jan 8 2026

Starting to see signs of the surface low shifting a bit more northwest, thus tracking overhead of the the CWA from the southwest to northeast this afternoon and evening. With this shift expecting the hazards to shift as well first being the band of higher rainfall confined mainly to our northwestern portions of the CWA. HREF continues to ping a band of +1" of rainfall through Sauk County into Marquette and Green Lake counties. Given the increased rainfall rates/totals, partially frozen ground temps, and potential for ponding and minor flood concerns both for low-lying areas/roadways and rivers from ice jams, will issue a Flood Watch from 3 PM CST this afternoon through midnight tonight for the aforementioned counties.

Meanwhile, this shift also brings the warm sector along with higher moisture (+1inch PWATs) into southeastern half of the CWA. Already seeing temps creep into the mid to upper 40s and even a few locations crack 50F late this morning. Given this shift, may overall see less rainfall for these areas, but there is a growing concern for isolated convection to develop later this afternoon and early evening as MUCAPE climbs to around 500 J/kg as the nose of the 50-60 kt LLJ pushes into WI. Thus a few elevated thunderstorms are possible and cannot rule out a stronger or storm or producing small hail and gusty winds at the surface through the evening. Main area of concern would be for a line southeast of Sheboygan to Monroe. So will see how things evolve over the next few hours.

Wagner

SHORT TERM

Issued 330 AM CST Thu Jan 8 2026

Today through Friday:

Quiet and mostly clear skies early this morning as high pressure lingers to the east. However high clouds are starting to push in associated with the next system developing in lee of the Rockies. This low pressure system will begin to push precip into the region by early this afternoon. This system will be associated with a strong shortwave aloft with strong WAA as a strong LLJ swings in as well as strong Fgen. Rain from this system will be light to moderate with the moist column and strong forcing.

However, as quickly as rain moves in we will quickly dry in the mid to upper levels as the dry slot swings in from the south. As the dry slot pushes in there will likely be some instability pushing in as well. Although we may not see much sunlight this may allow for a few storms to pop up within the dry slot for a few hours this evening. The low levels may remain fairly moist as well and with low level forcing around 850mb with the LLJ remaining strong, we may easily see drizzly type precip or even light rain well into the evening but the dry air aloft may impact lower than models currently suggest. Thus we we maintain 20-50% PoPs through the evening/overnight.

Late tonight into Friday morning the backside of the low will swing back through the region as the dry slot pushes out to the east and we will get a return of high precip chances. This will be due in large part to the backside LLJ and TROWAL and the backside of the upper trough and associated shortwave energy swing through with continued higher end moisture. The biggest thing acting against higher end PoPs and potential higher QPF is the drier midlevels, more limited forcing and any forcing being much more transitory. In any case, while this will be mostly rain, the front will have come through cooling temperatures within the column down and thus introducing some snow. Snow looks likely to be restricted to northwest and far western parts of the CWA where cooler temps prevail. While some snow may mix in no accumulations are expected.

By mid to late Friday morning we expected precip to push out with a brief period of high pressure overhead helping to keep us dry for a fairly short period of time before the next system pushes in Friday night.

Kuroski

LONG TERM

Issued 330 AM CST Thu Jan 8 2026

Friday night through Wednesday:

Low temps will be in the mid to upper 20s Fri nt with high pressure overhead. Skies should clear out for a period of time. Thankfully the column looks dry overhead so fog should not be an issue. Fri afternoon winds should help dry out any puddles in time for the freeze as well.

I wish I could say that the models came into better agreement for predicting the snowfall amounts for Saturday, but that is not the case. The predicament is whether or not the northern stream and southern stream upper lows will phase. Not only do the ECMWF and GFS deterministic models take turns phasing/not phasing with each run, but the ensemble members do that as well. This is nearly a boom or bust scenario for getting accumulating snow over southern WI on Saturday. I say nearly because everyone should get at least a tenth or two of snow in the unphased scenario since the northern stream upper low will still swing across the region.

If the upper waves phase, a swath of snow would spread into south central WI by mid Saturday morning and taper off in intensity by early Saturday evening. The overall precip amount (QPF) came down from the previous forecast and is now closer to a quarter inch. This could be as low as 0.05 (or lower) if we only receive precip from the cold core northern stream upper low.

Colder air will briefly settle into srn WI on Saturday night behind that low. Winds will be gusty out of the northwest, but highest if the systems phase. Lows in the teens to around 20 are forecast Sat nt and Sun nt with Sun highs in the 20s.

A clipper may cross WI on Monday and bring flurries and some gustier winds. A stronger clipper will swing across the Upper Great Lakes on Tuesday. Temperatures look to hover around the freezing mark through the column, so a rain/snow mix is forecast, along with gusty winds.

Cronce

AVIATION

Issued 1030 AM CST Thu Jan 8 2026

VFR conditions with high clouds will prevail through the morning hours before low pressure lifts into the area later this afternoon and evening. Expect lower MVFR/IFR to accompany the incoming moderate to heavy rainfall through the evening. Heaviest rainfall will be along and northwest of HWY-151 with lowest visibilities. Meanwhile areas southeast may see less rain as a bit more dry air moves in, but there is a growing potential for a few thunderstorms to develop into the evening. Expect to see lowest flight conditions if any thunderstorms move over a terminal. The bulk of the heavier rain will move out of the area by 03z with fog and drizzle persisting into early Friday morning keeping those lower flight conditions around longer, while another swath of light showers and even some wintry mix swings through by daybreak. Will see conditions improve through Friday morning as high pressure builds in and a return of VFR conditions.

Wagner

MARINE

Issued 330 AM CST Thu Jan 8 2026

Low pressure over the central Great Plains today will track northeast and strengthen as it crosses Lake Michigan by late tonight. Gusty south to southeasterly winds will occur over the southern half of Lake Michigan this evening as the low approaches, veering southwest late. Lighter east winds are expected for the north half of the lake.

As the low departs to the northeast early Friday morning, it swings a cold front southward across the lake. Gusty north to northwest winds are expected behind it, which will persist through early Friday afternoon. Both of these periods of gusty winds are expected to prevail below gale force but we cannot rule out a few gale force gusts. Meanwhile, a Small Craft Advisory remains in effect from 0z to 14z Friday for gusty winds.

Weak high pressure crosses the lake Friday night, with light and variable winds shifting east. Another low pressure system tracking northeast from Arkansas/Louisiana will pass south of Lake Michigan on Saturday. The west to northwest winds behind this system for Saturday night into Sunday may reach gale force over Lake Michigan.

Kuroski

MKX WATCHES/WARNINGS/ADVISORIES

WI...None. LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...6 PM Thursday to 8 AM Friday.