textproduct: La Crosse

KEY MESSAGES

- Light precipitation expected late tonight and Tuesday mainly along and north of Interstate 94. If the low levels are able to saturate fast enough there may be some light freezing rain (probability up to 15 percent) north of Highway 29 in north- central Wisconsin otherwise the precipitation will be snow tonight. On Tuesday, temperatures will be warm enough that any precipitation that falls would be rain. The highest probabilities (up to 30%) will be in north-central Wisconsin.

- Tuesday night into Wednesday is looking drier. Continued the trend of lowering or removing precipitation chances. It continues to look like it will be brisk with sustained winds will be in the 15 to 30 mph range and the wind gusts will range from 25 to 40 mph. The strongest winds will be west of the Mississippi River.

- There continues to much uncertainty on how cold it will be this weekend with large spreads between the 10th and 90th percentiles.

DISCUSSION

Issued at 246 PM CST Mon Jan 12 2026

Tonight into Tuesday

There continues to look like there will be 2 rounds of precipitation with a 500 mb shortwave trough that will be moving southeast through the region late tonight and Tuesday.

The first round of precipitation will be associated with the warm air advection ahead of this wave tonight. This will result in precipitation developing either late this evening or overnight. Like the past couple of days, there is plenty of uncertainty on how fast the boundary layer will saturate. The sooner that this occurs, the better chance of there being some light freezing drizzle/rain. The HREF probabilities for at least 0.01 inches of freezing rain has decreased from 30-50 percent in its 00z run to less than 15 percent in its 12z run north of Highway 29 in north-central Wisconsin. The 12z BUFKIT soundings suggest that by the time there is enough saturation for precipitation to occur, ice crystal seeding from aloft should be occurring and the precipitation would be mainly in the form of snow. Little, if any, snow is expected.

The second round of precipitation will be associated with the cold front as it moves southeast through the area. Like the past couple of days, there has been questions on whether we will able to saturate the air mass enough to produce light rain or not. Currently the best chance for that to occur is along and north of Interstate 94. Even then, the probabilities of measurable rain is only up to 30 percent (higher north of Wisconsin 29).

Tuesday night and Wednesday

Another 500 mb shortwave trough will move southeast through the Upper Mississippi River Valley and Great Lakes. With this wave moving more east of the local area, the precipitation chances were removed for much of the forecast area.

Like the past couple of days, the NBM winds continue to look too light for this time period, so used a 50-50 blend of the NBM and the NBM 90th percentile to raise both the sustained winds and wind gust. The sustained winds will be in the 15 to 30 mph range and the wind gusts will range from 25 to 40 mph. The strongest winds will be west of the Mississippi River.

Thursday into the Weekend

The models continue to show that a 500 mb longwave trough will develop across the eastern US. However, there continues to be many questions with this trough, such as, how will it be orientated, where will be the western periphery of this trough, where will the coldest core be located in this trough, ect. As a result, this impacts the storm track and temperatures. The largest 2 meter temperature spreads occur this weekend. On Saturday, La Crosse has a spread of 14F from 0F for the 10th percentile to 14F for the 90th percentile and Rochester has a spread of 16F from -5F for the 10th percentile to 11F for the 90th percentile at noon. The spreads for 2 meter temperatures increase even more for Sunday. La Crosse has a spread of 31F from -7F for the 10th percentile to 24F for the 90th percentile and Rochester has a spread of 34F from -11F for the 10th percentile to 23F for the 90th percentile at noon.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 545 PM CST Mon Jan 12 2026

Primary aviation concern over the next 24 hours is potential (30%) for light freezing drizzle along and north of an EAU-MFI line between 06z and 12z. No precip is expected to the south of this line and a transition to rain is expected by 12z. Other concern is potential for low level wind shear affecting valley terminals, including LSE, from around 06z this evening until 15z Tuesday morning as west-northwesterly low level jet ramps up atop light southerly surface winds in valleys. For ridgetops, surface winds will be southwesterly with higher speeds, precluding mentionable level LLWS. Finally, good signal for MVFR ceilings to spread southward during the latter portion of the TAF period, so have added this to RST/LSE TAFs.

ARX WATCHES/WARNINGS/ADVISORIES

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