textproduct: La Crosse

KEY MESSAGES

- Light snow chances (20-40%) this morning north of I-94 could bring a dusting.

- Messy wintry mix of snow, sleet, and freezing rain is likely to create slippery travel north of I-90 Sunday afternoon- evening. A glaze of ice and minor sleet accumulations are possible. Snow will be more favored to the north of I-94 with 0.5 to 3" possible.

- Milder temperatures next week but monitoring a couple systems on the horizon: light freezing rain potential (20% chance) late Monday night turning to rain on Tuesday, and a more potent late-week storm system.

DISCUSSION

Issued at 309 AM CST Sat Jan 3 2026

Light Snow Chances This Morning, Mainly North of I-94

A weak vort max embedded in northwest flow can be seen on water vapor pushing into northwest MN. Toward daybreak, this feature will dive southeast and bring a shot at some light snow through early afternoon, mainly north of I-94. Snow extent will largely hinge on whether the currently dry low levels can moisten sufficiently in conjunction with the incoming weak forcing. RAP/HRRR show a tongue of dry air in the 1000-850mb layer that extends up the Mississippi River Valley and encompasses southern WI. Corresponding forecast soundings show the greatest snow potential this morning to be north of I-94, particularly over Taylor and Clark counties. Meanwhile, other guidance is quicker to bring the low levels closer to saturation outside of north- central WI, suggesting the potential for flurries in other parts of the forecast area later this morning. Regardless, today's snow potential should be of little to no impact given the transient weak forcing and limited moisture. North of I-94, both the HREF and REFS max suggest a dusting, while NBM 95th percentile suggests locally up to 1 inch.

Messy Wintry Mix Brings Snow/Ice Sunday Afternoon-Evening

Overall details/timing: Main attention is on the increasing likelihood (now a 40-100% chance depending on location) for a messy wintry mix near and north of I-90. A deepening shortwave trough will eject from the Intermountain West Sunday morning, with strengthening isentropic lift and moisture return out ahead of it. Low level frontogenetic forcing will also likely form a north-south oriented band on the system's southern periphery, which high-res model reflectivity already depicts. As a whole, this system looks to be very progressive, which is good news from the standpoint of limiting overall amounts of messy wintry precipitation. CAMs are in good overall agreement with the system arriving midday Sunday around 11am-noon in our west, then quickly continuing east through the afternoon and largely exiting our area by 5-6pm. Any given location may only see precipitation last for a duration of 1-3 hours given how quickly it is progged to move through, but impacts could potentially linger through late evening north of I-94, closer to the heart of the system.

Precipitation types: Low level warm air advection will introduce a warm nose between 900-700mb, most pronounced south of I-94 where temperatures aloft could exceed +3C. If they reach this magnitude, falling hydrometeors would completely melt to liquid in the warm layer. A closer look at the surface cold layer in forecast soundings shows its depth may range from 2000-3000 ft along I-90. Generally 2500+ ft deep is more favorable for sleet, so will have to closely watch forecast trends over the next 24 hours to determine if sleet might end up being more favored than freezing rain. Still early to be splitting hairs between the two ptypes, as there are enough forecast factors that could end up favoring freezing rain more instead. For now, will continue to message the likelihood of a wintry mix between I-90 and I-94. Snow will be more favored the further north you go from I-94, but the wintry mix now looks like it may extend further north of I-94 than it did with earlier forecasts given the warm nose.

Precipitation amounts: Tricky...very tricky...as it will depend on ptypes and duration. Given the warmer, wetter airmass, snow ratios will be around 8:1 or less, favoring a wet/heavy snow variety. Where snow is most favored over Taylor and Clark counties, amounts should range from 0.5 to 3" (from south to north, respectively), which is in line with NBM's 75th percentile. Further south into the wintry mix, any sleet accumulations would be relatively minor. Ice accumulation from freezing rain is obviously the bigger concern, and if fzra would end up being the more favored ptype, much of the area between I-90 and I-94 could see up to 0.05", which is close to the NBM's 90th percentile. As mentioned above, forecast soundings are giving more of a look of sleet for this area, so not convinced freezing rain impacts will be quite so widespread. But will need to watch forecast trends very closely through Sunday morning.

Impacts: Regardless of ptype, the main message is this system will bring a messy wintry mix that is likely to create slippery travel near and north of I-90 on Sunday afternoon-evening. Into Sunday night, will need to watch if areas north of I-94 could see a lingering small chance of freezing drizzle.

Milder Next Week With A Couple Systems to Monitor

As a more zonal pattern takes hold next week with some low amplitude ridging, milder temperatures will return with daytime highs climbing well into the 30s and even mid 40s for some. Despite the milder conditions, there will be a couple systems to keep an eye on. Late Monday night could bring some light freezing rain that changes to rain during the day Tuesday. Then a more potent system is on the horizon sometime late week as a deep western trough crosses the Rockies.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 550 AM CST Sat Jan 3 2026

Current ceilings around 8-10kft will lower through the morning hours, becoming 3-4kft for most this afternoon. Those west of the Mississippi River are expected to see MVFR ceilings of 2-3kft develop instead. Ongoing light snow over eastern Minnesota and northern Wisconsin will shift southeastward through the morning hours, allowing for periods of snow and minor visibility reductions into the early afternoon, primarily along and north of I-94. Still can't rule out some flurries elsewhere this morning, but overall impact will be little to none. Overnight, there's some indication fog/mist may develop west of the Mississippi River, namely in the 03.07z NBM, which suggests 20-40% probabilities for visibility less than 5SM.

ARX WATCHES/WARNINGS/ADVISORIES

WI...None. MN...None. IA...None.