textproduct: La Crosse

KEY MESSAGES

- Measurable snow (potentially 1-3 inches) looking likely near Interstate 90 late tonight and on Tuesday morning.

- Rain later in the week (Thursday night and Friday) is looking far less likely, so transitioned the forecast drier.

DISCUSSION

Issued at 234 AM CST Mon Nov 17 2025

This Afternoon through Tuesday

The 17.00z ensembles are general agreement that the surface low will track southeast from eastern Nebraska through southwest Iowa and then east across northern Missouri and central Illinois. Soundings along Interstate 90 are slightly cold than they were yesterday indicating more of a chance of snow after midnight tonight and on Tuesday morning. Moderate to strong 800 to 600 mb frontogenesis continues to be shown south of Interstate 94. In addition, the lift is being enhanced by upper level divergence associated with the left exit region of the upper jet. The 17.00z HREF shows a narrow (1 to 2 county wide) 2-4 inch snow band along Interstate 90. The probability of matched mean indicate that there is a potential for localized 4-6 inch amounts. Hourly snow amounts will be likely up to a half-inch. Lowered the hourly temperatures overnight by a degree and the transition to all snow to 34 degrees. This resulted in a band of 2-3 inches which seems rather realistic considering the forcing and the DESI snow probabilities.

Thursday Night into Friday

Unlike yesterday, there has been significant shift southward track in the low pressure system that was supposed to affect the area during this time period. It is now forecast to move east through the Mid-Mississippi River Valley east into the Mid- Atlantic region. With this new track, the area is looking drier, so trended the forecast that way.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 440 AM CST Mon Nov 17 2025

CIGS: Mid level VFR cigs expected much of today, lowering into MVFR/IFR as we move through tonight. Could drop into LIFR at KRST toward 12z Tue - with short term guidance suggesting they would then hold through Tue afternoon.

WX/vsby: rain spreads in from the south this evening, mixing with and changing over to snow mostly after 06z. Vsby restrictions of 1- 2SM in the snow. Accumulations mostly on cold, grassy surfaces. Accums from 1 to 2" currently expected. Snow, wintry mix looks to exit east by Tue afternoon.

WINDS: easterly through the period, mostly around/below 10 kts.

ARX WATCHES/WARNINGS/ADVISORIES

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