textproduct: La Crosse

KEY MESSAGES

- A round of light snow moves into the region Saturday into Saturday night, mainly affecting areas east of the Mississippi River where there is a 20 to 50% chance of at least 1" of snow.

- A brief lull in precipitation chances to occur Sunday into Monday before low chances return off and on through the end of next week,

DISCUSSION

Issued at 311 AM CST Fri Jan 9 2026

Friday - Saturday: Chances for Light Snow Return

Early this morning, the surface low had tracked north and east of our area with precipitation coming to an end from west to east across the Driftless Region. Snow has failed to materialize thus far across the region and with precipitation waning, it's unlikely we'll see any areas of significant accumulation. Preliminary analysis shows warmer temperatures aloft than what was originally forecast/initialized into the models. A warm nose present on the 00Z MPX sounding shows evidence as to why rain has prevailed across the region. While in many cases cooling aloft usually helps to cool the low level isothermal profile below 0 deg C and allow for the transition to snow to occur, this is one of the times when the cooling wasn't quite enough to pull the low level temperatures below the 0 deg C isotherm. Precipitation should be out of the forecast area by around 12Z with dry conditions prevailing through the rest of the day today. Some places could even see some sunshine peaking through the high clouds.

With system 1 generally out of the way, it's time to look at system 2, which is continuing to look less and less impressive with each suite of new guidance. The upper level pattern looks very similar to previous model runs with two troughing regimes: one to the north across the Canadian Plains and the other across the South Central Rockies. Through tonight and into tomorrow, these are expected to come into phase with one another and create a fairly stout upper low across the Upper Midwest by Sunday. So if all of this is on track as before, why have totals come down so much? The simple answer? Moisture. The more detailed answer? Two weak surface lows are expected to form in conjunction with their respective upper lows/troughs. The northerly one is expected to track generally along the US/Canada border into the Upper Great Lakes. The southerly (and more prominent) surface low is expected to develop around the Lower Mississippi Valley and track northeast into the Ohio River Valley, forming in the left exit region of a 500 mb jet max. This southerly surface low is expected to bring an ample amount of moisture north with it. Over the last few days, the track of this southerly low has shunted even further to our southeast, keeping deep moisture well out of reach for us. In addition, the northerly system is expected to move a little quicker than before, with its associated cold front tending to wipe out what little moisture we still have across the area. So for many, the only snow we'll likely see now is along the frontal passage early Saturday morning which likely won't amount to more than a trace of snowfall.

There are still totals east of the river in the 0.5-1 inch range and this is likely due to a small pocket of deeper moisture making its way into Southwest Wisconsin ahead of the cold front from the northern system. As this moisture interacts with the lift from the surface boundary and upper low, this will allow for a bit more robust area of snow to develop Saturday morning. Overall, the best chances for snow remain to the east of our area as lake enhancement will likely help to boost totals closer to the lakeshore. Probabilities for 1 inch of snowfall have been relegated to east of the river with only places across North Central and Central Wisconsin seeing probabilities higher than 40%. Probabilities for 2 inches or more are virtually non-existent, outside of a small 10-20% chance for portions of the Chimney. Overall, this event is looking much less impactful than it was before with only light snow and minor accumulations expected.

Saturday - Mid Next Week: Brief Lull before Low Precip Chances Return

As the upper low and subsequent trough axis finally begin to move away from the region Sunday, our area will be under northwest flow aloft. This should remain pretty benign until Tuesday when mid range models have a shortwave disturbance dropping south out of Canada and into the eastern Great Lakes region. A fairly substantial area of deep moisture will drop south with this trough, creating chances for precipitation early Tuesday. Current indications are that this would start as rain before transitioning to snow as a cold front moves through the area. With the northwest flow staying put, low precipitation chances continue on and off throughout the week as bits of shortwave energy pass overhead. Temperatures will be at their warmest Monday and Tuesday with highs in the mid 30s to lower 40s. All other days should see near normal temperatures in the 20s to low 30s.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1201 PM CST Fri Jan 9 2026

This morning's MVFR ceilings have largely begun to scatter out leading to predominantly VFR conditions into the evening hours, but some lingering MVFR restrictions may continue over the next few hours primarily along and east of the Mississippi River. Overnight, a cold front moves west to east through the region, bringing another bout of MVFR ceilings, generally 1-2kft, and possibly a period of light snow as the 09.12z HREF depicts 20-40% probabilities of precipitation. There is also some potential for IFR visibility reductions in this snow, generally 20-50%. Northwest winds begin to increase behind the front, but will be strongest towards the end of the TAF period.

ARX WATCHES/WARNINGS/ADVISORIES

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