textproduct: La Crosse

KEY MESSAGES

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

- Low confidence (<25%) in precipitation potential today with heavy rain as the main concern should and where storms form.

- Precipitation chances return mainly in Wisconsin Friday night into Saturday and Sunday night into Monday. Current overnight diurnal timing limits storm strength and potential.

DISCUSSION

Issued at 1251 AM CDT Thu Jul 16 2026

Precipitation Potential Today:

As the northerly, dry and smoke contaminated air sags south through northern Wisconsin, the more moist air mass lingers across the southwestern half of the forecast area. While meager, a low level stretching axis will potentially cause precipitation similar to Wednesday. While high resolution model solutions suggests higher confidence, associated soundings limit any instability and overall upper level saturation. Storm strength will also be limited as shear values remain insignificant. Heavy rainfall will be likely should and where storms form as PWATs remain quite moist near 1.5".

Wildfire Smoke & Air Quality Concerns Through Today:

Main forecast concern continues to be poor air quality from Canadian wildfire smoke mainly from southeast Minnesota into southwest and central Wisconsin. Current forecast confidence for smoke impacts to continue through Friday morning, eventually lifting northeast with a slight change in the change in the synoptic pattern. Alleviation may be short lived as an upper level perturbation drags southeast through southern Canada, potentially advecting another, more transient, bout of poor air quality. Minnesota Air Pollution Control Agency expanded the Air Quality Alert in southeast Minnesota based on record poor air quality observations through Wednesday night.

Precipitation Potential Into Early Next Week:

The Upper Mississippi River Valley remains on the periphery of the quasi-Rex block centered over the Great Plains through the weekend, permitting synoptic mid to upper level perturbations to pass along northwest flow causing precipitation potential (GEFS/EPS/GEPS). Initial chances Friday night into Saturday currently remain confined locally to counties in central Wisconsin may require further southwestern brushing of PoPs depending on extent and strength of anticyclonic flow and higher heights over the southwest. While current overnight timing limits instability (GEFS/EPS) and therefore overall storm potential, later advection to this wave into Saturday would also raise more widespread storm concerns. Similar, limited confidence for subsequent synoptic wave into early next week (GEFS/EPS).

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 552 AM CDT Thu Jul 16 2026

Smoke from Canadian and northern Minnesota wildfires continues to reduce visibilities into the MVFR to IFR range and air quality across the region. The smoke will shift slightly more southwestward this morning, as it follows in the wake of a weak front, into portions of southeast Minnesota and northeast Iowa. This boundary will lift northeastward this afternoon and as it does, showers and storms may form (10 to 25%). There is a little uncertainty on the coverage of these storm due to the smoke. The smoke is expected to leave the region later tonight as a wind shift will help to shift it out of the region.

ARX WATCHES/WARNINGS/ADVISORIES

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