textproduct: La Crosse

KEY MESSAGES

- Rain chances return Thursday (15 to 30%), mostly impacting portions of northeast Iowa and southwestern Wisconsin, however amounts remain below 0.1".

- Rain likely (95%) for Friday morning and thunderstorms for Friday evening, with potential for severe thunderstorms Friday evening. There is a 40 to 80% chance for at least 1" of rain to fall Friday into Saturday.

DISCUSSION

Issued at 140 PM CST Wed Mar 4 2026

Today-Thursday: Mostly Dry and Mild

A low currently sitting over the southern Plains will move into the Midwest Thursday morning. This increases rain chances mainly for areas outside of our CWA. The better moisture transport remains in northern Illinois. This system has also shifted slightly southward so current PoPs have been lowered to 15 to 30% for portions of northeast Iowa and southwest Wisconsin. HREF probabilities for measurable precipitation have also lowered and are now between 30 and 60% in portions of northeast Iowa and far southwestern Wisconsin. Yesterday's forecast had a low chance of rain accumulations reaching 0.1" in Grant county. This chance has no dwindled to almost nothing based on the recent HREF probabilities. Another sign that the better moisture remains out of our forecast area. Temperatures for today and Thursday remain in the upper 40s to low 50s.

Friday: Rain in the Morning, Potential for Severe Storms in the Evening/Overnight

Heading into Friday, a deepening trough and resultant surface low eject out of the central Rockies and into the central Plains. Ahead of this low, strong moisture advection pushes northward into the Upper Midwest. As a result, PWATs are forecasted to be in the 1 to 1.25" range which is in the 99 to 99.5 percentile based on the NAEFS. Widespread rain with more rain in the evening to overnight, as the surface low moves through the region, will lead to quite a bit of rain over much of the forecast area. On the EFI side of the things, there is a footprint for 0.6 to 0.7 across our forecast area for QPF which indicates the amount of rain is on the higher side of climatological normal. Current NBM probabilities for at least 1" of rain falling between Friday morning and Saturday morning is between 40 and 80% for locations along and south of I-94. Current forecasted amounts are generally between 0.75 and 1.25" across the CWA. Given that there are areas that have frozen ground, around 6 to 17 inches of frost depth, this amount of rain may not be able to enter the ground and much of the falling rain may end up as runoff which could result in creek and river rises. One thing that could help alleviate the amount of runoff is that highs are well above freezing, in the upper 40s to low 50s for today and Thursday and upper 50s to low 60s for Friday, which will help warm up the ground and allow for more rain to enter the ground rather than end up as runoff.

In addition to the rain, there is a potential for severe thunderstorms to occur Friday evening and into the early overnight. As the low shifts into the region, strong southwesterly flow aloft, 35 to 50kts at 850mb, will be in place ahead of this low. Combining this with the south winds at the surface, there will be decent low level shear, however the instability is what may be lacking for more widespread severe weather chances. A couple of factors will impact how unstable the atmosphere can get. The first is how much can we recover given the morning rain and storms. Will this be enough to inhibit our temperatures from warming into the upper 50s to low 60s? Another thing to note is how far north the warm air can get. There remains quite a bit of uncertainty amongst models on how far north the warmer air can get. The GFS and RAP are the further north outliers while the NAM is the furthest south solution. Depending on which solution plays will determine the extent of the severe weather potential. One thing that is for certain is that there is currently a few hundred joules of MUCAPE available to give us thunderstorms. Based on the amount of shear and the extent of the warm sector, there is a slight risk (level 2 out of 5) for portions of northeast Iowa and far southwestern Wisconsin with a Marginal (level 1 out of 5) for majority of the rest of the CWA. CSU ML probabilities also show some severe threat over the entire CWA. We will continue to monitor this and hopefully models hone in on a solution over the next day or so. Saturday-Monday: Cooler Saturday, Pleasant End of Weekend and Early Next Week

A dry weekend is expected as we are in zonal to slightly southwest flow aloft. After a cold front moves through early Saturday morning, highs remain in the 40s, but northwest winds at 10 to 15 mph will keep feels like temperatures in the mid to upper 30s. Warm, southwest flow returns for Sunday and Monday which will help to increase temperatures into the upper 50s to low 60s for Sunday and the mid to upper 60s for Monday.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 535 PM CST Wed Mar 4 2026

IFR conditions are expected to return to areas west of the Mississippi overnight with stratus favored rather than fog tonight. Either way, should see extended IFR at many locations, including RST. Situation farther east is a bit more uncertain as conditions remain a bit drier there but still think at least lower end MVFR is probable. Should skies at ONA/LSE/PDC/OVS remain clear, will need to watch out for potential valley fog as winds remain light overnight before stratus spreads eastward. Southeasterly winds should bring additional moisture to the area tomorrow so stratus may hang on deep into the daytime hours once again.

ARX WATCHES/WARNINGS/ADVISORIES

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