965
FXUS63 KARX 201204
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
704 AM CDT Sun Sep 20 2026

.KEY MESSAGES...

- A cloudy and damp morning gives way to peaks of sun this
  afternoon.

- A 20-40 percent chance of showers Monday into Monday night,
  through impacts look to be minimal.

- Cooler and drier conditions are expected through much of the
  new week.

&&

.DISCUSSION...
Issued at 655 AM CDT Sun Sep 20 2026

Today: Light Morning Showers, Drying Out this Afternoon

The surface boundary that was situated across the Upper Mississippi
River Valley over the past day or so has shifted well south of
the region, taking the heavy rainfall south with it. A few
elevated showers will percolate through the morning, mainly
south of I-90, before drier air filters in from the north.
Cloudy skies likewise will start to break up by this afternoon,
but most locales will see more clouds than sun today. Highs
today should remain seasonably cool with readings topping out in
the mid-60s to around 70, dictated by the exact degree of cloud
cover we see.

Monday: Potential for Showers Returns

Monday into Monday night brings additional potential for
rainfall as the upper level closed low currently over the
northern Rockies shifts eastward into the Upper Midwest.
Currently thinking areas along and south of I-90 will be favored
to see shower activity during this period as the current
trajectory of the upper low and the placement of a surface
boundary suggests the strongest QG forcing should reside across
these areas.

Rainfall amounts should be on the lower side compared to the last
day or so with the 20.01z NBM suggesting amounts are favored to be
under 1 inch with only a 10-20% chance to exceed this amount. That
said, some flooding potential does exist, mainly across southeast
Minnesota and northeast Iowa, if amounts exceed 1 inch given the
saturated soils, but should largely be mitigated by fairly marginal
parameters for heavy rainfall.

Tuesday - Friday: Cooler and Drier

Cooler and more fall-like temperatures are in store for the Upper
Mississippi River Valley through much of the new week as high
pressure and lower heights become situated over the Great Lakes by
Tuesday with highs in the 60s to low 70s and lows in the 40s. A
drier airmass also sinks southward into the Upper Midwest during
this period, limiting any additional rainfall potential as we head
into next weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 539 AM CDT Sun Sep 20 2026

MVFR and lower ceilings are still being observed across the area
this morning. The low clouds should begin to lift after sunrise
and a return to VFR conditions is possible as early as 16-18z.
Brief MVFR conditions may continue through the afternoon, but
the current expectation is that once the sites become VFR, they
should remain that way through the rest of this TAF issuance.
The wind is forecast to stay out of the east over the next 24
hours with gusts up to 20-25 kts during the daytime hours.

&&

.HYDROLOGY...
Issued at 655 AM CDT Sun Sep 20 2026

Multiple area rivers remain above flood stage. The Cedar River
around Austin is cresting and expected to start falling today.
The crest is working down the Root River in Fillmore and Houston
counties with most locales touching minor flood stage today or
tomorrow before falling. Additional crests are working down the
Turkey and Volga rivers in northeast Iowa with minor to moderate
flooding ongoing or expected over the next few days. Confidence
in the degree of flooding along the Kickapoo is on the lower
side given that the river has been trending lower than forecast
with most locales only expected to touch flood stage at best.
Little additional impactful rainfall is expected today.

&&

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

&&

$$

DISCUSSION...Falkinham/Skow
AVIATION...Muscha
HYDROLOGY...Skow