La Crosse, Wisconsin 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

148
FXUS63 KARX 251742
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
1242 PM CDT Sat Apr 25 2026

.KEY MESSAGES...

- Outside of low, light precipitation chances grazing
  northwestern peripheral counties in southeast Minnesota and
  central Wisconsin, a mostly dry Sunday is expected before
  precipitation chances increase Sunday night through Monday
  morning.

- Strong to severe storm chances remain for Monday afternoon and
  evening primarily for the southern half of the forecast area
  from northeast Iowa into southwest Wisconsin. Local forecast
  area on northern periphery of higher confidence for stronger
  storms. All hazards (i.e., large hail, damaging winds,
  tornado) remain possible where severe storms form.

- Colder, slightly below normal temperatures expected through
  next week.

&&

.DISCUSSION...
Issued at 1231 PM CDT Sat Apr 25 2026

Today & Sunday:

Ongoing light precipitation grazing local northwestern peripheral
counties from southeast Minnesota through central Wisconsin has
had little to no local impacts outside of a sharp temperature
gradient resultant of diurnal heating influences raising
temperatures in the mid 60s from northeast Iowa through west-
central Wisconsin. Expect these light precipitation chances to
linger along the accompanying pressure saddle shrink/stretching
axis over these same areas into tonight. Eventual enhancement
in synoptic forcing from a subtropical jet streak seen nearing
the eastern Pacific on GOES upper level derived winds advects
the higher moisture northeast through the Upper Midwest through
the end of the weekend.

Sunday Night & Monday Morning Precipitation Chances:

Resultant increasing precipitation chances progress from west
to east through the local forecast area Sunday evening, becoming
widespread by Monday morning. Although, ongoing storms will be
outrunning increased instability within the warm sector as
isentropic upglide progresses northeast through the forecast
area. Therefore, while widespread, stronger storm chances
initially remain lower locally, they can`t be completely ruled
out as ongoing storms attempt to penetrate northeast while a
tightening pressure gradient associated with upstream
cyclogenesis affects the local forecast area. While enhancement
of a potential low level jet will ultimately depend on location
of cyclogenesis upstream of the forecast area, the additional
forcing along its terminus will encourage storm development,
currently expected along our western periphery.

Strong to Severe Storm Chances Monday Afternoon & Evening:

Similarly, northern extent of unstable airmass spreading northeast
through Monday remains dependent on location of cyclogenesis
upstream subsequently traversing/grazing the local forecast
area. Synoptic ascent from phasing of the mid level wave due to
strengthening of the subtropical jet streak along its base as
well as upstream of its axis will provide required forcing for
storm chances to reach the forecast area through the afternoon.
While LREF agreement in exact location of the low center has
increased slightly compared to previous runs, mesoscale-beta
factors will influence and cause mesoscale-alpha forecast
discrepancies until a much closer forecast hour is reached.

Ongoing morning storm coverage affecting sky cover and incoming
diurnal shortwave radiational budget may cause a slight
temporal or spatial displacement affecting northern extent of
more unstable air. Coincidental timing of upstream ancillary lee
cyclogenesis initially resulting in a double-barrel resemblant
low center causing an eventual zonal progression to the
afternoon/evening cold front will be another forecast detail to
closely monitor as forecast hour nears. While overall
confidence is lower to do local forecast area proximity to
severe parameters, all hazards will remain possible where severe
storms do form.

Slightly Below Seasonable Temperatures Through Next Week:

A Canadian Polar airmass attempts to poke south through the Upper
Mississippi River Valley through the middle of next week, raising
concerns for frost/freeze initially Tuesday night locally. While
initial timing of colder remains dependent on timing of trough
ejection, synoptic agreement for colder air settling into region
through the middle of the week increases some confidence for
near freezing overnight temperatures by the end of the week.
Coldest solution in the GFS/GEFS advects the 850mb 0C isotherm
through most of Iowa by the end of the work week. Irregardless,
current forecast confidence (80%) for slightly below normal
temperatures through the end of April.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1227 PM CDT Sat Apr 25 2026

A shortwave trough will move northeast through the area this
afternoon and evening. With very dry located below 700 mb, we
are only looking at mid and high clouds from this system.

&&

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

&&

$$

DISCUSSION...JAR
AVIATION...Boyne