544
FXUS63 KARX 191752
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
1252 PM CDT Wed Aug 19 2026

.KEY MESSAGES...

- Dry and pleasant today.

- Thunderstorm potential returns Thursday evening into Friday
  morning with the main hazard being lightning.

- Seasonal temperatures in the 70s to lower 80s are forecast each
  afternoon over the next week.

&&

.DISCUSSION...
Issued at 1240 PM CDT Wed Aug 19 2026

This Afternoon to Thursday Morning: Dry and Pleasant Conditions

A cooler, drier airmass will remain in place through the rest of
today into Thursday morning over the Upper Midwest. Pleasant
conditions are forecast during this time frame with light winds
and mostly clear skies. Light winds and clear skies tonight may
support the formation of some patchy fog, especially in the
river valleys of far southwestern Wisconsin. Otherwise, Thursday
will be a few degrees warmer with increasing cloud cover out
ahead of the next weather system.

Thursday Afternoon through Friday: Thunderstorm Potential

A shortwave trough, originating out of the Canadian Prairie
Provinces, is forecast to move southeast towards the Great Lakes
region Thursday into Friday. Out ahead of this system, mid level
moisture will increase which will result in the formation of showers
and thunderstorms from the Northern Plains down through the Upper
Midwest. Although it is possible a storm may be strong to marginally
severe as they move into the western CWA on Thursday evening,
confidence in that scenario is low since CIN is rapidly increasing
as storms approach the area. Flooding is not really a concern with
the storms either, as PWAT values are only near the 75th percentile
(based on sounding climatology from KMPX) and the storms should be
moving relatively quickly. The bulk of the precipitation should be
east of the area by sunrise on Friday. Cloud cover should clear out
throughout the day as drier air makes its way over the area once
again and temperatures should be able to rise up into the upper 70s
to lower 80s during the afternoon.

This Weekend into Next Week: Seasonal and Mostly Dry Conditions

Forecast guidance remains consistent in building a ridge of high
pressure across the western and central US with a trough across the
eastern US this weekend into the next work week. This pattern would
place the Upper Mississippi River Valley in between these systems,
which does lead to uncertainty regarding the exact details of the
forecast throughout this time frame. In general, this pattern favors
seasonal temperatures and mostly dry conditions. Ensemble forecast
guidance hints at the potential for some light rainfall early next
week, however that will highly depend upon moisture remaining over
the area as well as the precise track of upper level disturbances.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1240 PM CDT Wed Aug 19 2026

VFR conditions are forecast with this TAF cycle. Light and
variable winds are almost certain through much of this 24 hour
period. The wind will eventually shift to out of the southwest
at the terminals with the wind increasing up to 10 kts at the
end of this TAF issuance. Mostly clear skies are expected with
some high clouds moving in over the region.

&&

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

&&

$$

DISCUSSION...Muscha
AVIATION...Muscha