textproduct: La Crosse

KEY MESSAGES

- A few snow showers possible late tonight into Sunday morning. No impacts are anticipated.

- Warming trend for the early to mid portion of next week.

DISCUSSION

Issued at 200 PM CDT Sat Apr 18 2026

The breezy to gusty wind from this afternoon will diminish overnight with boundary layer decoupling. A short wave currently over central Saskatchewan, will descend southeast through the steep northwest flow aloft and arrive across the area after 06z. Moisture availability with this system will be limited to any attendant moisture with the system. The general consensus is there will be a brief period with a near saturated layer up to around 10 kft depth with a shallow dry layer below it. That saturated layer will be cold with much of it residing with in the dendritic growth zone and colder temperatures above that layer. Theta-e advection with the attendant moisture and good kinematic forcing with provide ample vertical ascent and hydrometeors development and snow shower formation. Not expecting any impacts with warmer road temperatures but it is possible some minor accumulations could occur on grassy areas.

High pressure will move into the region through the day on Sunday and will lead to gradual clearing skies and diminishing winds during the afternoon. Good radiational cooling conditions will setup Sunday evening before the high pressure system begins to pass to the southeast setting up the area in return flow. In addition, some high level cloudiness may arrive late Sunday night as well as theta-e advection begins to develop aloft. Currently have forecast lows in the 20s and with colder high temperatures in the 40s on Sunday, these lows still look on target. though some adjustments may be needed if clouds or warm advection arrive sooner than currently forecast.

Stronger warm advection will arrive late Monday with much warmer temperatures returning Tuesday through Thursday. An upper level low across the western CONUS on Wednesday will translate east into Thursday leading to steepening southwest flow aloft. The Gulf moisture stream will open up by Wednesday night along with the low level jet pointing into the western forecast area. This may bring an elevated thunderstorm chance Wednesday night. More widespread thunderstorms chances arrive Thursday and Thursday night as a cold front moves through the region. This synoptic setup is favorable for increasing deep layer shear through the day Thursday that would promote organized strong to perhaps severe convection. Cooler weather returns to end the week.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 653 PM CDT Sat Apr 18 2026

VFR conditions are expected this evening and into the overnight with increasing low-VFR cigs across the region closer to daybreak. Cannot rule out (20-40% chance) a couple of snow showers at KRST towards daybreak with accompanying MVFR cigs and vsbys. Otherwise, winds will decrease after sunset and remain from the west before increasing to 10-15 kts and switching to northwesterly for the afternoon on Sunday.

HYDROLOGY

Issued at 200 PM CDT Sat Apr 18 2026

Flood watches and warnings remain in effect for area rivers, including the Black, Yellow, and Wisconsin Rivers, mainly for Minor flooding. These are expected to crest within the next few days. No meaningful additional precipitation is expected through the weekend and into mid-next week. Apart from a few flurries today and tonight, conditions should remain dry through Wednesday.

ARX WATCHES/WARNINGS/ADVISORIES

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