textproduct: La Crosse

KEY MESSAGES

- Wintry mix concerns Monday night into Tuesday morning with potential for freezing drizzle. While near freezing surface temperatures and lingering drier air limit widespread confidence, HREF (02.00Z) probabilities of 20-50% for accumulating freezing drizzle dot the local forecast area.

- Gradual warming through midweek with perpetual rain chances increasing Friday night with possible heavy rain and thunder.

DISCUSSION

Issued at 1110 PM CST Sun Mar 1 2026

Wintry Mix Tonight:

As surface high pressure progresses east of the forecast area through the morning hours, return flow ramps up, attempting to moisten the Upper Mississippi River Valley airmass. Exit behavior of anticyclonic flow locally remains an important forecast detail as the drier air mass will create contention for location and amount of saturation, potentially causing a tight gradient or decaying precipitation signal as it advects east. While overall forcing will be on a weakening trend as the mid level low on GOES water vapor imagery near the Pacific West Coast gradually decays, fragments of low level frontogenesis could provide sufficient forcing for precipitation within the incoming moisture.

Accompanying low level WAA struggles to take shape as the anticyclonic flow lingers the 0C isotherm at 925mb over the forecast area into tonight. While, current forecast confidence for near freezing surface temperatures overnight limits overall confidence in precipitation type, the farther east and north saturation is able to occur, icing risk also increases. Current HREF confidence for freezing rain is highest (30-50%) in northeast Iowa initially Monday night, spreading into southwest Wisconsin and southeast Minnesota into Tuesday morning.

Temperatures & Rainfall Through The Week:

The gradual warm up continues through the week with daytime highs pushing into the mid 50s and potentially 60s through the weekend. Southwest flow through the central CONUS and a lingering meager baroclinic boundary strewn across the Upper Midwest perpetuates precipitation chances primarily along the southern half of the forecast area through the week. Precipitation chances capable of producing heavy rain and thunder increase Friday with GEFS (01.18Z) probabilities from 50 to 70% for 0.5" of QPF in 24 hours grazing locally southern most counties in northeast Iowa and southwest Wisconsin Friday night. While the warmer temperatures and moisture will ameliorate thickest snow and rain on snow ablation concerns by then, 15"+ frost depths will hinder ability of water run off should heavy rain occur.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 529 AM CST Mon Mar 2 2026

VFR conditions currently present across the area with a small cluster of stratus moving east/northeast around FL070-090. Lower stratus, currently creeping north across Central Iowa, will eventually work its way into our area later today with MVFR CIGs moving into the KRST terminal as early as this afternoon. Did not have enough confidence to include this early arrival in this package just yet as some guidance indicates scattering this afternoon but trends and observations will need to be monitored through the day. The brunt of the MVFR stratus will move in this evening, eventually impacting the KLSE terminal, likely after 06Z. Have included some PROB30s at KRST for the potential of freezing drizzle and MVFR visibilities with increased probabilities of precipitation overnight. Probabilities remain too low at KLSE to include with this package but as we get closer, this may need to be adjusted in future updates. IFR/LIFR CIGs look to move into SE Minnesota and NE Iowa late in the period, impacting the KRST terminal after the end of this package. Winds will remain out of the south through the day, peaking around late morning/early afternoon between 8-15 kts, before decreasing into the evening hours and slowly backing to the southeast.

ARX WATCHES/WARNINGS/ADVISORIES

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