textproduct: La Crosse

KEY MESSAGES

- Severe thunderstorms will be possible around 4 PM to 8 PM this afternoon in far southwestern Wisconsin and adjacent parts of northeast Iowa, southeast of a Oelwein IA to Richland Center WI line. A level 3 out of 5 risk for severe storms is present in southern Grant County WI and extreme southeastern Clayton County IA. Damaging winds and hail are the main threats but a tornado may be possible as well.

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

- Combined effects of precipitation last night into this evening and again tomorrow afternoon into Saturday will lead to rises on area streams and rivers. Flashier or already higher running basins such as the Kickapoo, Turkey, and Black, may see minor (5-40% chance) flooding.

UPDATE

Issued at 1153 AM CDT Thu Apr 2 2026

Ongoing Ice Accretion This Afternoon:

While surface temperatures have slightly warmed to near and a couple degrees above freezing, east surface winds have locked the colder air in place across much of the forecast area, limiting warmer air to the southern half of the forecast area. Resultant additional ice accretions being observed on trees and tree limbs causing concern for power outages through the early afternoon. Therefore, have extended the previous Ice Storm Warning until 18Z and issued a Special Weather Statement for potential power outages from downed trees and limbs.

DISCUSSION

Issued at 1217 PM CDT Thu Apr 2 2026

Strong to severe storm threat primarily lies along southern peripheral counties in far southwest Wisconsin this afternoon evening. As the surface low progresses east-northeast through the afternoon, a slightly more eastern jog is expected as storms near the forecast area, glancing the southern most peripheral counties in far southwest Wisconsin. Amount of clearing through the afternoon will determine available convective instability, subsequent northern extent of storms and intensity. Current confidence is limited for amount of clearing, keeping higher confidence mostly shunted to the south. Low level shear will support damaging winds and potential tornado should surface clearing occur, allowing storms to reach the surface.

Subsequent storm potential during additional cyclogenesis through the Central to Northern Plains Friday afternoon and evening. Similar eastern shunt to meso-low occlusion through the afternoon shunts more unstable airmass slightly south of the forecast area at current forecast hour. While a similar dependence and discrepancy between forecast models hinge on sky cover and associated availability of building instability north into the local forecast area, high resolution model discrepancies surrounding mid level lapse rates steepness affect storm solutions. While select models suggest steep lapse rates infiltrating through the local forecast area, an overall weakening trend limits confidence in strong to severe storms penetrating far north through the local forecast area. While high resolution model soundings suggest strong shear supportive of strong to severe storms, elevated storms limit severe hazards to damaging winds and hail. Timing will be slightly later, albeit dependent on cyclogenesis and synoptic forcing, lasting storm threat into the overnight hours.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1217 PM CDT Thu Apr 2 2026

IFR conditions are expected to be predominant over the next 24 hours. Ongoing rain will taper off this evening but low ceilings should remain. Some indication for fog in guidance but low level parameters suggest clouds will remain a few hundred feet off the surface. This moisture and thus stratus should (70%+) remain over the next 24 hours with additional rain expected after the period ends 18z Friday. Next good chance for widespread VFR isn't until Sunday.

HYDROLOGY

Issued at 1217 PM CDT Thu Apr 2 2026

Repeat rounds of heavier rainfall will cause rises on local rivers into the early weekend. HREF members suggest 48 hour totals of 2"+ from southwest into central Wisconsin. Flashier rivers such as the Kickapoo and potentially Turkey would therefore be initially impacted with rises. These QPF forecasts would ride river levels above Action near Minor Flooding at sites along the Kickapoo. However, given the convective mode of heavy rainfall, higher amounts are possible in select spots and warrant further monitoring in coming forecasts.

ARX WATCHES/WARNINGS/ADVISORIES

WI...Ice Storm Warning until 1 PM CDT this afternoon for WIZ017-029. MN...None. IA...None.