293
FXUS63 KARX 300602
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
102 AM CDT Wed Jul 30 2025

.KEY MESSAGES...

- A series of thunderstorm complexes will move through the area
  from tonight into Wednesday. With these systems being
  progressive, the threat of flooding remains low. In addition,
  with the better shear and stronger winds remaining north of
  these complexes, severe weather chances looks to be on the low
  side. If severe weather happened to occur, damaging winds will
  be the primary threat.

- Dry and cooler-than-normal temperatures are expected from
  Thursday through Saturday night.

- Rain chances return to the forecast for early next week.

&&

.DISCUSSION...
Issued at 106 PM CDT Tue Jul 29 2025

Tonight through Wednesday

For tonight and Wednesday, a series of shortwave troughs will move
east out of South Dakota and Nebraska and through the Mid- and Upper
Mississippi River Valley. 850 mb moisture transport will help
produce progressive mesoscale convective complexes which will move
east through our area. While the mixed-layer CAPES will range from
1000-1500 J/kg south of Interstate 90, the 0-3 and 0-6 km shear
remains weak (less than 15 knots). Dry air above 750 mb might result
in some localized wind gust of 30 to 40 mph in any collapsing cells.

Wednesday Night through Saturday Night

A surface high, currently centered over the Canadian Prairies, will
build south into the Upper Mississippi River Valley/Great Lakes on
Wednesday night and Thursday, and then remain located over these
regions into Saturday. This high pressure area then shifts east
southeast into the Mid-Atlantic region. High temperatures on
Thursday will be in the lower and mid-70s on Thursday, and then
range from the mid-70s to around 80 through the remainder of the
period. The winds aloft will be favorable for smoke through Friday
morning and then as high drifts further east, the smoke should drift
east of the area.

Sunday into Tuesday

Zonal winds will undercut the upper level ridge over the Canadian
Prairies. This will allow a shortwave trough to move east through
the region. This system will bring a round of showers and storms.
The timing of this rain remains uncertain due to variations on the
timing of this wave. High temperatures early in this period will
range from the mid-70s to around 80 and then warm into the
lower and mid-80s associated with a short-wave ridge in the wake
of this trough.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1245 AM CDT Wed Jul 30 2025

Ongoing precipitation embedded with scattered storms pushing
northeast through northeast Iowa at 30.06Z TAF issuance. Any
accompanying impacts locally have mostly remained MVFR. Stronger
storms southwest of the local forecast area in central Iowa
causing IFR visibilities.

Storms spread northeast through the morning hours. Current
confidence (50-80%) places northern edge north of both TAF
sites (KLSE & KRST). While RA will be widespread, coverage of
TSRA may be limited and require further adjustment in subsequent
TAF (30.12Z) issuance(s). A very moist atmosphere can cause
temporary LIFR reductions where storms impact. Storms shift
southeast out of the local forecast area tonight.

Besides low confidence (<20%) for river valley fog, overall VFR
expected into the weekend.

&&

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

&&

$$

DISCUSSION...Boyne
AVIATION...JAR