textproduct: La Crosse

KEY MESSAGES

- Light snow spreads southeast across the Upper Mississippi River Valley early this morning. Highest local accumulations of 1" to 2" expected in northeast Iowa and southeast Minnesota. - Low confidence (<20%) for light precipitation Monday Night and Wednesday. Moderate confidence (50%) for wintry mix Thursday.

- Near normal daytime highs Wednesday. Above normal daytime highs for Thursday.

DISCUSSION

Issued at 237 AM CST Sun Feb 1 2026

Light Snow Spreading Southeast This Morning:

Previous snowfall forecast for today remains on track as radar imagery loops show meridional bands of reflectivity progressing east through Minnesota early this morning towards the Upper Mississippi River Valley. Initial band of heavier (0.5"-0.75" hr-1) snowfall rates expected to be on the weakening trend upon reaching and progressing through the western half of the forecast area due to weakening frontogenetical bands and transient separation between the south-southeast digging low level trough and synoptic ageostrophic forcing.

Regardless, expect initial band to progress southeast through the forecast area this morning, providing 1" or more primarily west of the Mississippi River Valley and a Trace to 1" elsewhere. The frontal boundary and trough slowly advect through the forecast area through today, perpetuating light snowfall chances area wide before eventually increasing again north of Interstate 90 from southeast Minnesota through central Wisconsin later this afternoon and evening.

Subsequent Early Week, Low & Light Snow Chances:

While subsequent overall impacts through the start of the week appear minimal, progression of the antecedent mid level wave remains determining factor for local impact potential. A more northeasterly solution in the most recent GEFS (01.00Z) permits an open wave to graze the western periphery of Upper Mississippi River Valley, increasing subsequent precipitation chances Monday Night and Tuesday morning. Most recent GEFS (01.00Z) remains intra and inter-ensemble outlier with 20-40% probabilities for 0.01" of QPF in 6 hours in the western half of the forecast area. Box and whisker LREF sounding plots suggest precipitation type would be snow however light.

Another lower confidence (<20%) precipitation forecast for Wednesday as low level WAA excites from west to east and LREF QPF probabilities drop as they approach the Upper Mississippi River Valley. Higher, albeit moderate confidence (25%-50%) precipitation forecast for Thursday locally limited to Wisconsin as a longer, separated synoptic wave progresses southeast. Besides the GEFS, intra-ensemble confidence has decreased compared to previous runs as more solutions support a stronger surface low well to the northeast of the forecast area within the northern stream of synoptic forcing. Precipitation type could be a concerning factor according to ensemble sounding plumes with a few members of the GEFS & EPS aligning with many members of the GEPS with a warmer off surface layer and below freezing temperatures somewhere in western/central Wisconsin.

Near Seasonable Wednesday, Above Seasonable Thursday:

While LREF members disagree on strength and exact location of low shifting through the Great Lakes, all suggest a troughal appendage of colder air covering the Upper Mississippi RIver Valley through much of Wednesday. The earliest solution in the GEPS permits low level WAA Wednesday evening while the EPS/GEFS wait until Wednesday night. Regardless, all models suggest near or above normal temperatures for Thursday before confidence plummets and forecast spread widens for Friday.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 523 AM CST Sun Feb 1 2026

Band of snowfall causing quick, transient reduction in visibilities to IFR-LIFR through central Minnesota seen nearing KTOB and KRST shortly after 01.12Z TAF issuance. Expect IFR visibilities as snowfall passes this morning and again this evening primarily north of Interstate 90. Confidence for lingering snowfall and accompanying intensity through the day remains the largest unknown. Have continued MVFR visibilities at KRST with stronger winds and proclivity for reductions while TEMPO'ing IFR at KLSE should stronger snowfall occur.

ARX WATCHES/WARNINGS/ADVISORIES

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