060
FXUS63 KARX 081738
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
1238 PM CDT Sat Aug 8 2026

.KEY MESSAGES...

- Periodic bouts of showers and storms expected through
  Wednesday of next week. These may produce heavy rain and
  severe weather at times. If severe weather does occur,
  damaging winds would be the main threat. Any flooding will be
  highly dependent upon whether storms can repeatedly move over
  the same areas.

&&

.DISCUSSION...
Issued at 1238 PM CDT Sat Aug 8 2026

Tonight and Sunday Morning

Currently watching a shortwave trough over eastern Montana. The
08.12z models are in general agreement that this wave will move
southeast through the area overnight tonight and on Sunday morning.
While there is general agreement with the upper level features,
there is plenty of uncertainty in the CAMs on how convection
will initiate and where it will track from tonight into Monday
morning.

Some CAMs suggest that storms will develop near the North
Dakota/South Dakota/Minnesota borders during the mid- to late
evening. Over time as cold pools coalesce develop this
convection will form into a line will track southeast along and
south of Interstate 94 overnight and on Sunday morning. In this
scenario, strong to severe straight-line winds would be
favorable. However, the timing of this line does not look favorable
for widespread severe winds due to the instability gradually
waning overnight.

Other CAMs suggest that the MCS, currently over Nebraska, will move
east across Iowa. Eventually a linear MCS moves east across Iowa
tonight. Like the previous scenario, the primary severe weather
threat would be damaging winds. However, this time it would be
mainly south of Interstate 80.

Low temperatures tonight will range from the mid-50s to around 60
along and north of Interstate 94, and in the mid-60s elsewhere.

Sunday afternoon and night

Another shortwave trough, just moving into Washington State, will
move east southeast through areas areas along and south of
Interstate afternoon during the afternoon and evening. The models
suggest that there will be some recovery during the afternoon. How
much recovery is still highly uncertain. Surface-based CAPES will
likely range 1-3K J/kg in parts of southeast Minnesota,
northeast Iowa, and southwest Wisconsin. The better instability
will be found along and south of a weak boundary in this area.
With 0-6 km shear forecast to be in the 35 to 45 knot range,
scattered supercells will be possible. With the better speed
shear being located in the 0-3 km layer, damaging winds will be
the primary threat with maybe an isolated tornado threat.

With warm-layer clouds depths around 4 km and precipitable water
values from 1.5 to 2.5 inches, any showers and storms will be highly
efficient rain producers. Fortunately, the storm motions should be
fast enough to minimize the flooding threat.

High temperatures on Sunday will range from the mid-70s to lower
80s. Low temperatures on Sunday night will range from mid-50s to
around 60 along and north of Interstate 94 and in the mid-60s
elsewhere.

Monday afternoon and Monday night

Some weak cyclogenesis is forecast to develop over eastern South
Dakota. A front will extend east southeast across southern
Minnesota, northern Iowa, northern Illinois, and southern Wisconsin.
Surface-based CAPES will be 2-3K J/kg south of this front and up to
2K J/kg north of this front. With unidirectional westerly flow
in the mid-levels, there is a potential for pockets of damaging
winds in any bowing cells.

With warm-layer clouds depths around 4 km and precipitable water
values between 1.5 and 2 inches, any showers and storms will be
highly efficient rain producers. With the front not expected to move
much, there could be some training cells which would increase the
flooding threat.

High temperatures on Monday will range from the around 80 to mid-
80s. Low temperatures on Monday night will range from mid-50s to
around 60 along and north of Interstate 94 and in the mid-60s
elsewhere.

Tuesday into Wednesday

A front will continue to meander south of Interstate 94. As
shortwaves track east southeast across the area, there will be
periodic showers and storms. Strong zonal flow in the mid-levels may
result in some periods of damaging winds. In addition, with
precipitable water values in the 1.5 to 2 inch range, these
showers and storms will be highly efficient rain producers.

High temperatures on Tuesday will range from the mid-70s to mid-80s.
Low temperatures on Tuesday night will range from mid-50s to around
60 along and north of Interstate 94 and in the mid-60s elsewhere.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1238 PM CDT Sat Aug 8 2026

Clouds and visibilities will be mainly VFR through Sunday
morning. Some CAMS suggest that a line of storms may impact the
TAF sites late tonight and Sunday morning. Confidence remains
low, so kept the the PROB30s.

&&

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

&&

$$

DISCUSSION...Boyne
AVIATION...Boyne