textproduct: La Crosse

KEY MESSAGES

- Fog through early this morning, mainly east of the Mississippi River where the heaviest rain fell yesterday. Visibilities may touch a quarter of a mile at times.

- Dry conditions today and tonight with the risk for storms returning Sunday afternoon into Monday, which could produce locally heavy rain.

- Trending hot for the middle to end of next week with highs likely in the 90s and heat indices approaching the 100 degree mark.

DISCUSSION

Issued at 1250 AM CDT Sat Jun 6 2026

Today: Fog Early, Dry

Surface/upper level ridging builds into the area through today. With recent rainfall, light winds, and clear skies overnight, fog is forming across areas along and east of the Mississippi River, which may spread a little west closer to sunrise. The higher probabilities of a quarter mile or less visibilities will across north central Wisconsin. The rest of the day is dry with above normal temperatures reaching into the mid to upper 80s for highs.

Sunday into Monday: Rain Returns, Locally Heavy

As ridging builds over the Great Lakes region, southerly flow returns over the central United States. This will advect deeper Gulf moisture into region through the day on Sunday. Precipitable water values increase to near 2 inches by 00z Monday. Upper level trough embedded in the southwesterly flow aloft will track into the Upper Great Lakes/Northern Plains States Sunday into Monday. With decent moisture convergence/ forcing associated with the upper level trough, expect showers and storms to increase in coverage Sunday afternoon into Monday. Given the deeper moisture and prolonged nature of the rainfall, rainfall amounts of 1-2 inches are not out of the question (currently 40% for 1 inch south of I-90 and about 10% for 2 inches).

Rest of the Week: Trending Hotter

As we head late into the week, an upper-level ridge will become situated over the local area resulting in southerly low-level flow across the local area. As this occurs, moisture advection will result in dewpoints increase fairly dramatically across the local area with the grand ensemble (GEFS/EC/Canadian ensemble) having high probabilities (70-90%) for dewpoints in the 70s. This coupled with highs approaching the 90s would suggest that we could see heat indices approaching the 100F mark. Some conflicting guidance between the bias-correction in the NBM and the raw models leads to some uncertainty in exactly how warm we will get. But given the EC Extreme Forecast Index has a fairly strong probability footprint (70-90%) for temperatures to exceed model climatology, thinking temperatures will be fairly above normal, just a matter of how much above normal and if any finer details such as precipitation potential would keep us cooler.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 530 AM CDT Sat Jun 6 2026

Shallow LIFR fog mainly north of a RGK to LSE to DLL line burns off quickly after sunrise with VFR conditions for the rest of the TAF period. Winds will be light (<5 kts) and variable through the period as they gradually swing to the east and southeast early Sunday morning.

ARX WATCHES/WARNINGS/ADVISORIES

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