textproduct: La Crosse

KEY MESSAGES

- Dangerous and potentially historic winter storm moves into the region beginning this evening.

- Snow will be favored throughout the overnight and morning hours on Sunday north of I-94 with snowfall rates of 2-4 inches per hour likely in Taylor County. Impactful freezing rain and sleet is expected for the I-90 corridor on Sunday morning where ice accumulations of up to 0.25" will be possible.

- By late Sunday afternoon/early evening everyone in the forecast area will see snow. Winds increase Sunday afternoon and continue through the overnight with sustained northwest winds of 25 to 35 mph with gusts of 45 to 55 mph. This will result in blizzard conditions across the forecast area.

DISCUSSION

Issued at 243 PM CDT Sat Mar 14 2026

This Evening - Early Sunday Afternoon: Heavy Snow North of I-94 with rates of 2-4"/hr, Wintry Mix Near I-90.

Well it is the calm before this storm this afternoon as the upper- level shortwave associated with our advertised high impact winter storm has moved onshore in the Pacific Northwest. As a result of this, have noticed some model shifts this morning primarily in the HRRR/RAP which has noticed a fairly dramatic shift south in its 12z/15z runs with it positioning the surface low shifting from northern IA to southern IA during the morning hours on Sunday, something that we thought could occur in previous forecast cycles here at the 11th hour. Overall, the expected evolution with our potentially historic winter storm favors an initial warm advective wing of light snow that develops from west to east generally I-90 on north around 6-8pm and gets progressively more intense in snowfall rates through this evening and into the overnight. As the warm advection increases aloft throughout the overnight, a fairly pronounced warm nose can be noted in the HRRR/RAP soundings at KLSE during the early morning hours on Sunday. As a result, expecting a transition from the initial light snow over to sleet/freezing rain for the morning hours on Sunday within the vicinity of the I-90. With this strong warm advection moving in ahead of the deepening low a remarkable sloping frontogenetic signal develops across the region with fairly robust instability atop this frontogenetic layer. As a result, precipitation rates will likely be quite intense during the Sunday morning timeframe, especially for areas near I-90 and northward.

Along the I-90 corridor this period of intense forcing will likely manifest as potentially heavy sleet and freezing rain on Sunday morning with the 14.12z HREF having respectable probabilities (40-70%) for freezing rain accumulations of 0.25" or greater. Additionally with the convective nature of this, could see some fairly rapid accumulations of sleet where this is the favored precipitation type with the 14.12z HRRR having a small axis of 1-2" of just sleet on Sunday morning near I-90. In addition to this, MUCAPE values approach 200 J/kg atop this frontogenetic layer which will not only aid in increasing precipitation rates, but could result in some thunder during this sleet/freezing rain period on Sunday morning.

Further north, particularly in northern Clark and Taylor counties, an all snow solution seems to be the highest confidence scenario throughout the entire event as the warm nose does not manage to make its way into north-central WI. During this morning period in Taylor County snowfall rates will likely be very impressive as the 14.15z RAP has a profound 700mb frontogenetic signal over north-central WI which is situated squarely in the dendritic growth zone. In addition, some instability atop this layer will add additional fuel for snowfall rates to become potentially absurd. Currently, the 14.12z HREF has high confidence for snowfall rates in excess of 2 inches per hour during the 3am to 8am, primarily north of Hwy 29 in Wisconsin. Furthermore, the HREF even has a probability (10-20%) footprint for even 4"/hr snowfall rates in north-central WI, something almost never seen in this part of the country. This period in particular will be extremely dangerous as it is completely feasible north of Hwy 29 in Wisconsin that you could pick up 12-18" or more of snow in a 6-12 hour period on Sunday morning. Thinking with the instability above the frontogenetic layer some thundersnow cannot be ruled out as well. One thing we will need to watch is that recent CAMs have exhibited a southern trend in their most recent runs, this may result in the heaviest snow totals shifting closer to the I-90 corridor with a faster transition to snow. If this happens these 2-4"/hr rates at times may reach further south, perhaps into Wabasha through Jackson counties where then the probability for 12- 18+" totals would increase dramatically. In any case, this will be an extremely dangerous period, in all honesty travel throughout the day on Sunday really should be avoided expect for emergencies.

Sunday Night-Monday: Blizzard Conditions Sunday Night into Monday Morning, Much Colder Temperatures

This part of the forecast has remained largely unchanged over the past few days. The surface low moves over the Great Lakes and in the process of shifting eastward it deepens. Another thing item to talk about that has been in development over the last couple of models runs is another push of moisture that comes up during Sunday evening and into early Monday morning. As a result, more snow would be possible as this secondary plume of moisture comes up. Using the low to mid level frontogenesis, this also shows up as a secondary band, indicating that snow rates could increase for much of the area. This tightens the pressure gradient and increases surface winds. Currently we have 25 to 35 mph sustained northwest winds with gusts between 40 and 50 mph, with some potential to reach 55 mph. As the winds increase, the snow band shifts and orients itself in a southwest to northeast orientation. This band then gradually shifts off to the east. In addition, a deformation band of snow develops as low to mid level frontogenesis increases. With this deformation band, snow may continue longer into Monday morning and snow rates will be higher. Total snow accumulations are varied across of the forecast area. The highest amounts are currently focus north of Highway 29 with 2 to 3 feet possible. Between Highway 29 and the I- 90 corridor, generally looking at 10 to 20 inches with the lower totals closer to I-90. For northeast Iowa, snow totals range from 4 to 10 inches. For far southwestern Wisconsin into central Wisconsin, snow totals are roughly 6 to 18 inches with the lower amounts in far southwestern Wisconsin. There are some caveats to these totals, particularly around the I-90 corridor and far southwestern Wisconsin. For the area around I-90 and into northeast Iowa, there has a been a southerly trend in the recent models pushing some snow amounts higher across the I-90 area. This could result in totals more closer to the 12 to 18 inch range when the storm is all said and done as snow would be starting earlier than previously forecasted. Another caveat is where the secondary push of moisture ends up. This would impact snow totals in far southwestern Wisconsin the most. All in all snow totals are a little uncertain still given the timing of when the rain to snow transition occurs and where exactly the secondary push of moisture occurs. Stay tuned for for updates heading into the overnight!

At the tail end of this event, while it is still snowing, much colder air shifts over the area. Low temperatures in the single digits to low teens are expected Monday morning. With the wind still howling during the overnight, feels like temperatures end up in the single digits and teens below zero!

Tuesday-Wednesday: Light Snow Chance

As northwest flow aloft continues into early next week, this helps a shortwave dip down into the Upper Midwest and increase snow chances Tuesday evening into Wednesday morning. Current LREF probabilities for at least 1" of snow is 50 and 75% across the forecast area. The cooler weather continues as highs only get into the low 20s. These temperatures are dependent on how much snow we get as the morning temperatures could be colder than currently forecasted in most locations due to the light winds and mostly clear skies. Regardless, high temperatures will be at least 15 to 25 degrees below normal.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1236 PM CDT Sat Mar 14 2026

Widespread VFR conditions continue through the rest of the afternoon. Heading into this evening, lowered flight categories begin in north central Wisconsin and gradually shift south during the early overnight resulting in most locations being in the IFR to LIFR range for both visibility and CIGS. Snow begins to spread into north central Wisconsin this evening. Snow rates will be quite high approaching 2 to 3 inches per hour at times heading into the overnight and morning period. While light snow is possible for areas south of I-94 during the evening and early overnight, a wintry mix of freezing rain, sleet, and snow is expected for areas along the I-90 corridor. Further south into northeast Iowa and southwest Wisconsin precipitation will start out as rain. Eventually all precipitation switches to snow by Sunday evening. Precipitation type changeover times are still uncertain and could result in snow starting across much of the region as early as mid Sunday morning. Southeast winds shift to northeast winds Sunday morning and increase as they switch. By mid Sunday morning most locations will see sustained winds of 15 to 25 mph with gusts of 30 to 40 mph.

ARX WATCHES/WARNINGS/ADVISORIES

WI...Blizzard Warning from 10 AM Sunday to 7 AM CDT Monday for WIZ017-029-032>034. Winter Weather Advisory from 1 AM to 1 PM CDT Sunday for WIZ054-055. Winter Storm Warning from 7 PM this evening to 10 AM CDT Sunday for WIZ017-029-032>034. Winter Storm Warning from 7 PM this evening to 1 PM CDT Monday for WIZ041>044-053. Winter Storm Warning from 1 PM Sunday to 1 PM CDT Monday for WIZ054-055-061. MN...Blizzard Warning from 10 AM Sunday to 7 AM CDT Monday for MNZ079-086>088-094>096. Winter Storm Warning from 10 PM this evening to 10 AM CDT Sunday for MNZ079-086>088-094>096. IA...Winter Weather Advisory from 1 AM to 10 AM CDT Sunday for IAZ008-009. Blizzard Warning from 10 AM Sunday to 7 AM CDT Monday for IAZ008-009-018-019. Winter Weather Advisory from 1 AM to 1 PM CDT Sunday for IAZ010-011. Blizzard Warning from 1 PM Sunday to 7 AM CDT Monday for IAZ010-011-029-030.