658
FXUS63 KARX 121747
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
1247 PM CDT Wed Aug 12 2026

.KEY MESSAGES...

- Periodic storm chances through the weekend. Any severe potential
  looks low at this time.

- Temperatures remain near normal over the next few days before
  slightly cooling this weekend into early next week.

&&

.DISCUSSION...
Issued at 1152 PM CDT Tue Aug 11 2026

Early This Morning through Thursday: Storm Chances Continue

Scattered thunderstorms have developed across central to west
central Wisconsin at the time of this writing. The environment
remains largely supportive for the potential for storms to become
severe given sufficient CAPE and shear. The main factor that is
still lacking over the area is upper level lift. Storms earlier this
evening struggled to sustain themselves and the current expectation
is that the trend will continue, even though the storms right now
are more widespread and have stronger cores than earlier. It is
unknown how long these storms may last but they could go for at
least a few hours early this morning.

Another potential for storms, some of which could be severe, may
reach the far southern counties in our CWA Wednesday morning. A
shortwave trough, that is currently moving across the Dakotas, will
continue to quickly move east to southeast overnight into Wednesday
morning. The forcing provided by that feature combined with
sufficient moisture will likely lead to yet another storm complex
moving towards the Midwest going towards sunrise. Right now, the
current expectation is that most storms will remain south of
the CWA, but a few counties in northeastern Iowa or southwestern
Wisconsin may get clipped by the northern extent of the line.
Model guidance indicates a tight H700 theta-e gradient setting
up across northern Iowa towards the WI/IL state line by
Wednesday morning. So the line of storms is anticipated to stay
along and south of the gradient. If any storms are able to get
far enough north into the area, the potential for severe storms
will remain in place with damaging wind gusts being the primary
hazard. If any storms do move in, they should quickly move east
out of the area by mid to late morning.

Isolated thunderstorm development will remain possible in the
afternoon on Wednesday, but the lack of synoptic scale forcing
should keep storm coverage on the lower end. Another shower and
storm complex will likely move out of the Plains towards the Midwest
on Thursday morning. The potential for severe storms at this time is
quite low. Even though there is expected to be morning convection
both on Wednesday and Thursday, temperatures should be able to rise
into the upper 70s to 80s both afternoons.

Friday to Early Next Week: Cooler with Continued Rain Chances

Upper level ridging elongates over the upper Midwest on Friday but
will quickly weaken this weekend into early next week as the center
of high pressure weakens and moves back west towards the southern
High Plains. Even though H850 temperatures increase on Friday into
Saturday over the region, persistent cloud cover along with the
potential for rain showers and storms will keep temperatures in the
70s to low 80s. Speaking of the rain potential, mid level moisture
increases Friday into Saturday with southwesterly to westerly flow
over the region. Shortwaves embedded in the flow will provide
opportunities for widespread showers and storms, with the highest
chances (60-80 percent) on Friday night into Saturday morning. Heavy
rain will be possible with this activity as mean ensemble PWAT
values increase up to 2 inches on Saturday morning. Some flooding
concerns may arise given this potential, especially with more
chances for rain Saturday night into Sunday. Rain chances may
continue into the new work week as shortwaves continue to move over
the northern Plains towards the Great Lakes. Temperatures during
this time period will remain a few degrees below average in the 70s
to lower 80s.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1243 PM CDT Wed Aug 12 2026

A lack of overall surface or near surface smoke impacts resulted
in removal of previous mention for 12.18Z TAF issuance.
Therefore, subsequent impacts will be low potential for Fog
(30%) overnight into Thursday morning and subsequent storm
chances moving west to east shortly thereafter. Highest local
probabilities expected along and south of Interstate 90,
therefore south of local TAF (KLSE/KRST) sites at the current
forecast hour. Additional fine tuning will be required in coming
forecasts as northern extent of storm chances becomes
increasingly clear.

&&

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

&&

$$

DISCUSSION...Muscha
AVIATION...JAR