778 FXUS63 KARX 270434 AFDARXArea Forecast Discussion National Weather Service La Crosse WI 1130 PM CDT Fri Sep 26 2025
.KEY MESSAGES...
- High pressure will provide dry weather through much of next week. As a result, the forecast is dry with enhanced chances of warmer-than-normal temperatures.
&&
.DISCUSSION... Issued at 1236 PM CDT Fri Sep 26 2025
Tonight and Saturday
A 500 mb shortwave trough will move through the region late tonight and Saturday morning. This system will have little moisture to work with, so other than a wind shift there will no impact to the sensible weather. With increasing winds and shallow boundary layer moisture tonight, the fog potential looks very low. Low temperatures tonight will be in the 50s tonight and high temperatures will range from the mid-70s to lower 80s.
Saturday night through Thursday
In the wake of the system tonight and Saturday, a 500 mb ridge of high pressure will build across the Upper Mississippi River Valley and eventually the Canadian Prairies. If Imelda comes into the southeast United Sates early next week, a Rex Block would gradually develop. This will keep the forecast dry through this time period. Even if does not develop, the strong 500 mb ridge will keep the area dry. High temperatures will range from the mid-70s to lower 80s for this time period. Currently, the high temperatures for Wednesday and Thursday are in the lower and mid-70s. If these trends continue, these temperatures will have to be eventually raised into the 75th percentile which ranges from the mid-70s to lower 80s.
&&
.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1130 PM CDT Fri Sep 26 2025
CIGS: SKC/SCT through the period with some high level (15-20kft) clouds attached to a passing trough/cool front today. Some threat for low stratus at KLSE Sunday morning.
WX/vsby: only concern is for the potential fog/low stratus at KLSE the next few mornings. T/Td spreads, sfc winds, and the depth of the light wind layer, will be the main factors to keep an eye on. As of now, RAP/NAM suggest the vert wind speeds will be too brisk to support fog late Sat night/Sun morning - but could lighten up enough for 300 ft stratus to spread across KLSE. Something to watch.
WINDS: winds will swing west/northwest with the passage of the cool front this morning. Some increase to around 10+ kts post the front, but those settle down Sat evening as a sfc high moves back in.
&&
.ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None.
&&
$$
DISCUSSION...Boyne AVIATION.....Rieck
NWS ARX Office Area Forecast Discussion