FXUS63 KARX 200823 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 323 AM CDT Wed Aug 20 2025 .KEY MESSAGES... - River valley fog continues through the mid morning and may form again Thursday morning. - Showers and storms may return Friday (20 to 35%) as a cold front moves through the region. - Seasonable temperatures through the week with below normal temperatures beginning this weekend and lingering into early next week. && .DISCUSSION... Issued at 323 AM CDT Wed Aug 20 2025 Today-Friday: Seasonable and Mostly Dry Midweek, Showers and Storms for Friday? Latest satellite imagery continues to show fog expanding in many of the river valleys. This is expected to continue through the mid morning and may occur again Thursday morning as light surface winds, saturated low levels from rain that occurred over the weekend, and clearing skies are expected to linger. Surface high pressure continues to build into the region as well as the northeast flow in the low levels. Despite this normally meaning we are dry, there is a slight uptick in the moisture transport this afternoon that could result in a shower or two in central and southern Wisconsin. The confidence on this occurring is low, so have opted not to bring in higher PoPs for these areas. With the high pressure in place, high temperatures remain near normal through the week with temperatures in the upper 70s to low 80s. Heading into Friday, a cold front ahead of a longwave trough sweeps down from the northern Plains and impacts our CWA later Friday afternoon and evening. PWATs rise again into the 1.2 to 1.5 inch range ahead of the front with dewpoints returning to the upper 60s to low 70s. Instability builds out ahead of the front as well with MLCAPE values up to 1500 J/kg. Showers and thunderstorms are expected fire out ahead of the front, however confidence in their location and how widespread the development will be has kept PoPs between 20 and 35%. This can also be seen in the moisture transport as it is weaker than Thursdays moisture transport over the northern Plains. Saturday-Early Next Week: Cooler Temperatures Drier conditions are expected behind the cold front, however with cyclonic flow on Saturday, showers may form on the backside of the surface low. After Saturday, PWATs dip below 1 inch as the drier air lingers over the area. Cooler air comes down from Canada as the longwave trough dips into the region with 850mb temperatures between 4 and 8C from Saturday through Tuesday, with the coolest temperatures on Sunday and Monday. EFI values are also highlighting early next week with values of -0.7 to -0.9 for the high and low temperatures. With these values, the EFI is indicating that these forecasted temperatures would be on the lower end of the climatological normal. Current forecasted highs for this period are in the mid 60s to low 70s with overnight lows in the upper 40s to low 50s. There are even some low 40s forecasted for Tuesday morning. With dewpoints decreasing for the weekend and these temperatures, it is shaping up to be a pleasant weekend and beginning of next week! && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 1245 AM CDT Wed Aug 20 2025 Similar to last night, light winds at the surface and just above the surface, saturated conditions from the previous days rain, and generally clear skies, widespread fog is expected to develop early this morning causing lowered flight categories into the IFR/LIFR range. Some areas may see dense fog, however how much dense fog we see is uncertain. All fog and low clouds dissipate by the mid morning and VFR conditions resume with light northeast winds. && .HYDROLOGY... Issued at 323 AM CDT Wed Aug 20 2025 River flooding continues on parts of theTurkey, Trempealeau, and Cedar Rivers as a result of the weekends rain. A few gauges remain in minor flood stage as of this morning and are expected to remain there through at least today. As a result, river flood warnings remain in effect for portions of these rivers. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Cecava AVIATION...Cecava HYDROLOGY...Cecava