textproduct: La Crosse

KEY MESSAGES

- Ongoing heavy rain locally affects parts of northeast Iowa into far southwest Wisconsin with 2 to 2.5 inches of precipitation expected through today.

- Cooling trend into new week increases frost/freeze concerns mainly Monday morning.

DISCUSSION

Issued at 120 AM CDT Thu Oct 1 2026

Today: Widespread Rainfall

A widespread area of moderate rainfall is slowly making its way north and east out of the Central Plains and into the Mid/Upper Mississippi River Valley. Heavier rainfall is just making it into Northeast Iowa and Southwest Wisconsin late overnight with the heaviest of the precipitation still back near the core of the low around Omaha, NE. That will trek NE through the remainder of the overnight hours and through the morning. This will be co-located with precipitable water values in the 1.6-1.9 inch range. The latest 01.00 HREF 6 hour precipitation LPMM shows a few blotches of 3.5-4 inches across far southern portions of Fayette, Clayton, and Grant Counties. While there is still a 15-30% chance for 3-4 inches in those aforementioned locations, more likely totals will be closer to 2-2.5 inches.

There will be a fairly sharp northern cutoff in QPF with locations outside of Northeast Iowa and Southwest Wisconsin likely not seeing more than 0.5 inches of rain by 12Z Friday, evident in a sharp cutoff of precipitable water values in 01.03 RAP analysis. PWATs drop off to less than 1.5 inches as one moves north of the IA/MN state line with moisture transport more prominent south of our area across Southern and Central Iowa. This moisture transport will continue into northeastern Illinois and southern Wisconsin where the axis of heavy rain will extend by morning. The heaviest rain should push off to the east by mid morning as a cold front starts to move in from the northwest. Rain chances will gradually end through the day with most locations dry by 00Z Friday.

Thursday Night - Friday Night: Dry and Slightly Cooler

High pressure is expected to build in behind the aforementioned cold front. High temperatures Friday will be slightly cooler in the upper 50s to low 60s with lows Thursday night in the upper 30s to upper 40s. Friday night lows will drop into the mid 30s to mid 40s and some places across central and north central Wisconsin could see their first areas of frost this fall.

Saturday - Mid Next Week: Low Rain Chances Sat PM, Dry to Follow

Another cold front is expected to move southeast through the region Saturday afternoon/evening. Low potential for weak scattered showers across portions of Southeast Minnesota and West Central Wisconsin Saturday evening accompanying frontal passage but overall QPF amounts remain low, from 0.01-0.02 inches. This would be a quick hitter and likely wouldn't even have much of an impact on temperatures as highs Saturday and Sunday will be comparable in the mid 60s. The only thing of note would be the potential for frost across portions of Central and North- Central Wisconsin Monday morning as low temperatures could fall into the mid-30s across that region. Otherwise, high pressure looks to keep conditions dry next week with high temperatures generally in the 60s to near 70 degrees.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 549 AM CDT Thu Oct 1 2026

Ongoing rainfall will continue through the early morning hours, exiting east of much of the local area within a couple hours of 01.12Z TAF issuance. Subsequent potential for a narrow band of MVFR ceilings through the later morning hours before VFR conditions and strengthening north winds through the daytime hours.

ARX WATCHES/WARNINGS/ADVISORIES

WI...Dense Fog Advisory until 7 AM CDT this morning for WIZ017-029. MN...None. IA...None.