textproduct: La Crosse

KEY MESSAGES

- Main forecast concern continues to be wildfire smoke causing unhealthy to hazardous air quality this afternoon into Friday morning for the northeastern half of the local forecast area from southeast Minnesota into southwest and central Wisconsin.

- Medium-low confidence (20-40%) in precipitation potential today with heavy rain as the main concern where storms form.

- Next best chances for widespread rain/storms looks to come early next week Monday into Tuesday with a low chance (less than 15%) of seeing some strong to severe storms.

DISCUSSION

Issued at 122 PM CDT Thu Jul 16 2026

Rain Chances This Afternoon and Evening

Early this afternoon, a small cluster of showers has formed along and west of a quasi-stationary front draped across SE Minnesota and NE Iowa. The airmass in this area is very unstable with 2000-3000 J/kg of SBCAPE with little to no capping west of the boundary where smoke has stayed much more diffuse, if present at all. These showers are very pulse-like in nature though as shear remains hard to come by with less than 20 kts of effective shear expected through the afternoon. Some of these may develop into storms with some marginal lightning threat later this afternoon as destabilization continues through the afternoon. The main impact with any showers and storms will be heavy rainfall as PWats across the region are still around 1.5 inches. And given the lack of steering flow, storms will tend to sit over the same area so they will drop all their water in one place. A quick 0.5-1 inch(es) of rain won't be unheard of in locations under these showers given some of the QPF seen from yesterday's showers in the same airmass and overall setup. Some brief gusty winds can't be ruled out with some collapsing cores given DCAPE values over 1000 J/kg across the region but it's unlikely any gusts reach strong to severe thresholds. These showers and storms will gradually drift northeast into the evening hours with the boundary and dissipate as diurnal heating wanes and the nighttime inversion sets back up.

Smoke and Air Quality Concerns into Friday

Near surface smoke lingers across most of SE Minnesota and Wisconsin this afternoon with hazardous air quality conditions lingering into tomorrow. Visibilities have improved for many outside of North Central Wisconsin to around 3-5 miles with locations further north that are more solidly in the fetch of dense smoke still at or below 2 miles. Air quality index values for much of the area remain in the unhealthy to hazardous categories and this is expected to linger into tomorrow morning before smoke finally starts to move northeast as southwesterly low level flow starts to pick up through the morning hours. Air quality alerts for both Minnesota and Wisconsin run through 11am/Noon Friday with any extensions to be decided upon tomorrow. Unfortunately, this may not be the end of the smoke as round 2 of smoke may come back for Saturday as winds turn back to the north and pull some of that smoke back south. It's still uncertain as to whether air quality alerts will be needed for this potential second round of smoke but it will be something to monitor over the next day or two.

Precipitation Chances into Early Next Week:

The next solid chance for precipitation across the region looks to come Monday into Tuesday as the upper ridge retrogrades to the west and allows for a modestly strong shortwave trough axis to drop south/southeast out of the Western Hudson Bay/Manitoba and into the Upper Midwest. While instability in the range of 2000-3000 MUCAPE and strong vertical shear look to coincide on Monday, the main question will be with convective inhibition given an expected stout EML in place. As this is 5 days out, there is still plenty of time for things to change and shift but this looks to be the next time we could see some widespread rain and maybe some severe weather. Surface high pressure looks to build in behind this as we transition to northwest flow aloft. Luckily for us, this means cooler temperatures in the 70s and 80s are on the horizon for next week to give us some relief from this blistering 90+ degree heat.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 644 PM CDT Thu Jul 16 2026

Scattered showers and storms will move across southeast Minnesota early this evening and western Wisconsin through the early overnight. It will then be mainly dry across the Driftless region through the remainder of the TAF period. Between 17.06z and 17.14z, valley fog will cause IFR/MVFR ceilings and visibilities.

ARX WATCHES/WARNINGS/ADVISORIES

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