FXUS63 KARX 220008
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
708 PM CDT Fri Aug 21 2026

.KEY MESSAGES...

- Scattered storms possible in southwest Wisconsin early this
  afternoon, some of which may be on the stronger side.

- Seasonal temperatures continue into next week with highs in 
  the 70s to lower 80s.

- Dry weekend with the next potential round of storms coming
  Tuesday and Wednesday of next week.

&&

.DISCUSSION...
Issued at 1220 PM CDT Fri Aug 21 2026

Early this Afternoon: Storm Potential

As of midday, our weak cold front stretches along a line from 
near Oelwien, IA to east of Eau Claire, WI. Forecast profiles 
in the prefrontal airmass show ample instability on the order of
2000-2500 J/kg of MLCAPE, but the wind profiles--while linear 
to the southeast--will initially struggle to support organized 
convection given that the stronger mid to upper level flow looks
to not arrive until 21-00Z. By the time the stronger flow 
arrives and the hodographs elongate, the front will have 
progressed out of the forecast area and taken the severe weather
threat with it. Therefore, while one cannot rule out a pulse 
storm capable of producing lower end severe hail in southwestern
Wisconsin between 18-21Z, the main severe weather threat window
for the day continues to look to be just to the south and east 
of the forecast area. 

It is also worth noting the 175-200 J/kg of 0-3-km CAPE 
available in southwestern Wisconsin ahead of the front. If a 
local surface vorticity max were to co-locate under an updraft 
for a prolonged period of time, we could see landspout processes
in play. 

Saturday - Midweek: Dry Early, Storms Return Tuesday

Northwest flow returns to the region for the weekend as a 
trough amplifies to our east and the ridge sets up to our west. 
This ridge decays as it moves eastward into early next week. 
With our region in between these two features and under the
influence of surface high pressure, we look to be mostly dry 
and slightly cooler through the weekend until the ridge breaks 
down on Tuesday. High temperatures stay in the low 70s to low 
80s from Saturday through Monday. 

It will not be until Tuesday as a shortwave crests the
flattening ridge that the next risk for storms arrives with the
medium range ensembles in good agreement (60-80%) that there 
will be storms during this period. The exact timing and 
placement details of this rain will be hammered out as we get 
closer to the event. Beyond Tuesday, the forecast is looking
relatively dry for the middle to latter part of next week as the
upper level ridge rebuilds to our west.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 650 PM CDT Fri Aug 21 2026

Moderate (60-80%) for VFR through the 22.00Z TAF period outside
of Wisconsin River Valley FG affecting KOVS. While low
confidence (<15%) due to northwest winds ushering in a locally 
drier airmass, Mississippi River Valley FG affecting KLSE TAF
site would be short lived and limited impact should low level
saturation manage to come to fruition overnight into Saturday
morning.

Northwest winds increase through Saturday.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.

&&

$$

DISCUSSION...Skow
AVIATION...JAR