


Area Forecast Discussion
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
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480 FXUS63 KARX 081958 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 258 PM CDT Wed Oct 8 2025 .KEY MESSAGES... - Areas of frost in portions of western and central Wisconsin tonight and Thursday morning. - Increasing shower chances (30-50%) Thursday night areawide. Rainfall amounts of under 0.1" are generally expected. - Slight warming trend into the weekend and early next week with highs in the middle 60s to 70s for many. && .DISCUSSION... Issued at 258 PM CDT Wed Oct 8 2025 Tonight - Thursday Morning: Additional Frost Potential For West- Central Wisconsin GOES-19 water vapor imagery and 08.15z RAP 500mb heights depicts our region currently being subjected to northwesterly flow with an upper- level trough situated to our east and a ridge to our west. As a result, we have a corresponding region of high pressure directly overhead which has entrenched a cooler airmass in place. As we head into the overnight hours, this surface high pressure system will slowly push eastward allowing a relatively stronger pressure gradient to sneak in west of the Mississippi River and increase our surface winds slightly. Therefore, while the cooler airmass that has resided in our region the last couple days remains in place, really only expecting frost potential across portions of west/north-central WI where winds will more likely remain light enough to contribute to frost formation. Consequently, have issued a Frost Advisory for these areas through 9am on Thursday. Thursday - Friday: Showers Overnight Thursday Thursday will feature the aforementioned surface high pressure center pushing east of the local area allowing for slight moderation in temperatures as the upper-level ridge further west tries to nudge its way into the local area. However, its approach into the region will be delayed as a shortwave that will cut-off into a closed low pushes southeast out of Ontario and into the Great Lakes region. As this occurs, a frontal boundary will push through the area with some weak convergence out ahead. Consequently, noting fairly uniform shower development within the CAMs during the late evening Thursday through the overnight. This is seconded by the grand ensemble (GEFS/EC/Canadian ensemble) which has very high (60-80%) probabilities for measurable precipitation during this period. As a result, have increased precipitation chances from the national blend in accordance with these model trends. This Weekend & Early Next Week: Trending Slightly Warmer, Occasional Rain Chances By the weekend the aforementioned upper-level ridge begins to slide directly overhead allowing for a slightly warmer airmass to advect into the region resulting in highs trending near to slightly above normal. Sunday may feature the passage of a subtle shortwave that may increase our precipitation chances for the second half of the weekend. Consequently, noticing some fairly high probabilities for measurable precipitation (50-80%) in the grand ensemble (GEFS/EC/Canadian ensemble) during the Sunday into Monday period. The pattern for next week begins to favor an upper-level trough situating over the western CONUS with the upper-level ridge directly overhead. As this trough very slowly tries to meander eastward, shortwave perturbations will meander through the flow into the Plains and Upper Midwest which may increase precipitation chances throughout the week. However, the resolvability of any particular shortwave at this time remains low. Regardless, would expect temperatures to remain warmer than normal with southwesterly flow into the area and at least some periodic chances for precipitation into next week. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1243 PM CDT Wed Oct 8 2025 VFR conditions continue over the next 24 hours as high pressure remains the primary influence over the region although the typical river valleys may see patchy fog develop again overnight. Light and variable winds continue for portions of Wisconsin this afternoon with southeasterly winds elsewhere. Winds over Wisconsin will veer to the southeast tonight into Thursday. Gusts of 10-15kts are possible overnight into Thursday, primarily west of the Mississippi River, further increasing towards the end of the TAF period. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...Frost Advisory from 4 AM to 9 AM CDT Thursday for WIZ017-029- 033-034-041>044-053-055. MN...None. IA...None. && $$ DISCUSSION...Naylor AVIATION...Falkinham