textproduct: La Crosse

KEY MESSAGES

- Storm chances increase this evening into tonight primarily along western peripheral counties in southeast Minnesota with higher confidence for storm initiation from southern through central Minnesota weakening while shifting east.

- Lingering storm chances through Monday with warming temperatures into midweek, question of 90 degree isotherm coverage and duration remains current confidence detail.

DISCUSSION

Issued at 1245 AM CDT Sun May 24 2026

Storm Chances Through Tonight:

Scattered, non-severe storm chances increase through Sunday evening as storms are expected to initiate west-northwest of the local forecast area from southern into central Minnesota on the nose of increased low level moisture transport and accompanying frontal boundary. A east-southeast storm progression due to mean west- northwest flow with a sagging meager upper level perturbation seen upstream through the Canadian Rockies on GOES upper level water vapor imagery drags higher storm chances through the forecast area into the nighttime hours. While local mid level lapse rates sustain meager off surface instability through much of the daytime, very dry low level air and a lack of shear limit local confidence earlier through the day and/or stronger storms into the nighttime hours.

Precipitation & Storm Chances Through Monday:

Depending on southeastern progression of frontal boundary through Sunday night, local storm chances may linger through Monday morning and potentially Monday evening (<20%) as low level moisture transport reinvigorates along our western periphery. Low level anticyclonic flow keeps overall, widespread local confidence lower however. Similar lower confidence locally for precipitation through midweek as anomalous (90th+ percentile 500mb heights ABR SPC RAOB Climatology) heights build through the Central CONUS.

Warm Through Midweek:

Similar to previous forecasts, warmer temperatures expected through midweek with limited spread in most recent NBM (24.03Z) near 90 degrees Tuesday through Thursday. Unfortunately these higher temperatures seem overwhelmingly influenced by bias corrections evident in comparisons to raw model inputs, 3-7 degrees higher depending on exact local locale. Therefore, have toned down 90 degree mention by blending in some slightly colder model solutions, bringing daytime highs down a couple of degrees, still in the mid to upper 80s to grazing the low 90s Tue/Wed. Will be a detail to continue monitoring should NBM bias correction continue to skew a warm bias in the forecast.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 551 AM CDT Sun May 24 2026

Patchy to areas of fog are around this morning in many river valleys. This fog will dissipate by mid-morning. Mostly clear skies expected for today until this evening. Showers and storms move into southeast Minnesota and western Wisconsin between 05Z and 08Z. These showers and storms move southeast across the region and move into southern and central Wisconsin by the late morning hours on Monday. CIGS during the rain will be mostly be around 4kft to 8kft. Southwest winds generally between 5 and 15 mph expected through the TAF period.

ARX WATCHES/WARNINGS/ADVISORIES

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