Area Forecast Discussion
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
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056 FXUS63 KARX 121101 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 601 AM CDT Wed Aug 12 2026 .KEY MESSAGES... - Periodic storm chances through the weekend. Any severe potential looks low at this time. - Temperatures remain near normal over the next few days before slightly cooling this weekend into early next week. && .DISCUSSION... Issued at 1152 PM CDT Tue Aug 11 2026 Early This Morning through Thursday: Storm Chances Continue Scattered thunderstorms have developed across central to west central Wisconsin at the time of this writing. The environment remains largely supportive for the potential for storms to become severe given sufficient CAPE and shear. The main factor that is still lacking over the area is upper level lift. Storms earlier this evening struggled to sustain themselves and the current expectation is that the trend will continue, even though the storms right now are more widespread and have stronger cores than earlier. It is unknown how long these storms may last but they could go for at least a few hours early this morning. Another potential for storms, some of which could be severe, may reach the far southern counties in our CWA Wednesday morning. A shortwave trough, that is currently moving across the Dakotas, will continue to quickly move east to southeast overnight into Wednesday morning. The forcing provided by that feature combined with sufficient moisture will likely lead to yet another storm complex moving towards the Midwest going towards sunrise. Right now, the current expectation is that most storms will remain south of the CWA, but a few counties in northeastern Iowa or southwestern Wisconsin may get clipped by the northern extent of the line. Model guidance indicates a tight H700 theta-e gradient setting up across northern Iowa towards the WI/IL state line by Wednesday morning. So the line of storms is anticipated to stay along and south of the gradient. If any storms are able to get far enough north into the area, the potential for severe storms will remain in place with damaging wind gusts being the primary hazard. If any storms do move in, they should quickly move east out of the area by mid to late morning. Isolated thunderstorm development will remain possible in the afternoon on Wednesday, but the lack of synoptic scale forcing should keep storm coverage on the lower end. Another shower and storm complex will likely move out of the Plains towards the Midwest on Thursday morning. The potential for severe storms at this time is quite low. Even though there is expected to be morning convection both on Wednesday and Thursday, temperatures should be able to rise into the upper 70s to 80s both afternoons. Friday to Early Next Week: Cooler with Continued Rain Chances Upper level ridging elongates over the upper Midwest on Friday but will quickly weaken this weekend into early next week as the center of high pressure weakens and moves back west towards the southern High Plains. Even though H850 temperatures increase on Friday into Saturday over the region, persistent cloud cover along with the potential for rain showers and storms will keep temperatures in the 70s to low 80s. Speaking of the rain potential, mid level moisture increases Friday into Saturday with southwesterly to westerly flow over the region. Shortwaves embedded in the flow will provide opportunities for widespread showers and storms, with the highest chances (60-80 percent) on Friday night into Saturday morning. Heavy rain will be possible with this activity as mean ensemble PWAT values increase up to 2 inches on Saturday morning. Some flooding concerns may arise given this potential, especially with more chances for rain Saturday night into Sunday. Rain chances may continue into the new work week as shortwaves continue to move over the northern Plains towards the Great Lakes. Temperatures during this time period will remain a few degrees below average in the 70s to lower 80s. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 600 AM CDT Wed Aug 12 2026 Areas of fog have overspread portions of the Upper Mississippi Valley early this morning. LIFR conditions have been reported at the terminals this morning and this will likely continue for the next hour or two before lifting after sunrise. VFR conditions should prevail after that. Some near surface smoke may impact the terminals this afternoon and evening but visibilities will should stay VFR. Winds will remain light and variable. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Muscha AVIATION...Barendse