textproduct: La Crosse

KEY MESSAGES

- Sleet will change over to freezing rain overnight and continue into Thursday morning. The greatest icing will be Clark, Jackson, and Taylor counties where anywhere from 3 tenths to a half inch of ice may accumulate.

- There will be a potential of severe weather in southwest Wisconsin and adjacent northeast Iowa this afternoon. This will be associated with a few discreet supercells along a cold front. The main severe weather threats will be large hail, damaging winds, and isolated tornadoes. If they were to occur, it would be between 2 pm and 8 pm

- There will be another possibility for severe storms on Friday night. If they occur, the main threat will be large hail.

DISCUSSION

Issued at 211 AM CDT Thu Apr 2 2026

Overnight

During the evening, there was trend upward in the dew points west of the Mississippi River. They climbed into the mid-30s. There was some thoughts that the freezing rain threat might shift north, but as the precipitation rates declined, the dew points once again dropped below freezing.

Through the night north of Interstate 94, the warm nose will gradually warm and grow in depth. As this occurs, the sleet will gradually transition to freezing rain. Additional icing amounts will likely range from a tenth to around a quarter inch in Clark, Jackson, and Taylor counties.

Further south between the Interstate 90 and 94 corridors, the freezing rain is expected to continue through much of the night. Like further north, the warm nose is expected to warm and grow in depth overnight. As precipitation continues to fall into the shrinking cold pool near the surface, the surface temperatures will gradually warm and the freezing rain threat will come to an end. This will likely occur close to sunrise. Icing in these areas overnight will likely see anywhere from a light glaze to a tenth of an inch.

Elsewhere, rain is expected to continue with additional rainfall totals of a quarter to a half-inch.

This Morning

Along and north of Interstate 94, the warm nose will gradually grow in depth and magnitude. As this occurs, the freezing rain will transition to rain. As infrared radiation from the sun (even through the thick clouds) increases during the day, any additional icing will be more on elevated surfaces. Additional icing will likely range from a tenth to a quarter inch. These totals are higher than what they looked like they would be yesterday.

Like yesterday, there does not look to be much additional icing between Interstates 90 and 94 as either the freezing rain threat would have ended or will end shortly after dawn as warm air aloft is brought down from aloft by the rain.

This Afternoon and Evening

As the surface low moves northeast out of the Missouri into the Upper Mississippi River Valley, there should be some air mass recovery in the wake of the morning convection. There continues to be plenty of uncertainty on how much recovery there will be and how much of the area will be possibly impacted. At this time, it looks like it would be just southwest Wisconsin and the adjacent portions of northeast Iowa. There appears to be just enough shear (45 knots) and CAPES (up to 1000 J/kg) for a few discrete supercells along the cold front. This might result in large hail, damaging winds, and maybe an isolated tornado. If severe weather occurs, it would between 2 PM and 8 PM.

Friday Night

Another low pressure system will track across across the Upper Mississippi River Valley. This is a very similar track to the one this afternoon, but it doesn't move into the area until night. With less instability, the severe weather threat looks to remain mainly south of the area. If it did occur, the main threat would be large hail from elevated storms.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 1259 AM CDT Thu Apr 2 2026

Rain is ongoing south of I-90 with freezing rain beginning to build in between I-90 and I-94. Freezing rain is expected to continue for these areas into the mid morning hours. Rain will be the only precipitation type for areas south of I-90. Some light snow is expected for areas north of I-94 before transitioning to freezing rain during the overnight. All locations will see a switch to rain by the late morning hours. MVFR to IFR CIGS are currently being seen along and south of I-90. These lowered CIGS will gradually push further northeast and encompass the entire area during the overnight. These lowered CIGS are expected to hang around through the TAF period. Visibility's hang around the MVFR range during the overnight before dropping into the IFR category later this morning. East to southeast winds shift to northwest winds this evening.

HYDROLOGY

Issued at 139 PM CDT Wed Apr 1 2026

Overall rain totals for the first system range from a 0.5 inches to 1.5 inches. Some locations could see slightly higher totals given the convective nature of the rain later in the day on Thursday. Given the antecedent dry conditions, basins should be able to handle this first batch without too much cause for concern. Rises are expected with some of the flashier basins potentially going into action stage before this first round. Unless we significantly over-achieve on totals, this first round should be a healthy rainfall.

In the wake of the first system, additional rainfall amounts of 0.5 to 1.25", localized amounts up to 2 inches, will increase the risk of flooding on some area rivers. While confidence in any flooding is low, confidence for how river rises will manifest will increase further after the rainfall from the system tonight and into Thursday occurs.

ARX WATCHES/WARNINGS/ADVISORIES

WI...Winter Weather Advisory until 10 AM CDT this morning for WIZ032-033-041>044-053-055. Ice Storm Warning until noon CDT today for WIZ017-029. Ice Storm Warning until 10 AM CDT this morning for WIZ034. MN...Winter Weather Advisory until 10 AM CDT this morning for MNZ079-086>088-095-096. IA...None.