Special Weather Statement, NWS La Crosse, WI

Area Forecast Discussion
National Weather Service La Crosse WI
707 AM CDT Wed Jul 1 2026

.KEY MESSAGES...

- Several rounds of severe storms for the remainder of the week,
  bringing the risk for mainly damaging winds and heavy rain.
  The main time periods for severe weather in the next 24 hours
  are early this morning and again later this afternoon and
  evening.

- Warm and muggy conditions persist for the remainder of the
  week, but heat indices will be slightly cooler than the start
  of the week and shifting to the south.

- More seasonable temperatures for the holiday weekend, though
  shower/storm chances exist (40-60%).

&&

.DISCUSSION...
Issued at 1200 AM CDT Wed Jul 1 2026

Early this Morning: First Round of Storms

Another convective complex is progged to develop on the nose of
a 30-40 kt LLJ in northern Iowa after 06-09Z and translate NE
through the morning hours. Damaging winds will be the main
concern with these storms quickly becoming outflow dominant and
not last too long given the compact/complex hodographs but ample
MUCAPE values of 1500-2000 J/kg. The recent CAMs are all
depicting this feature in some way shape and form with the
explicit gusts from the HRRR hitting 50-60 kts in small pockets
from south-central MN into west-central WI. The other area of
focus with these morning storms is if/where they lay out an
outflow boundary that could modulate the threats and area of
concern for storms later in the day.

This Afternoon/Evening: Round 2 of Severe Storms

Confidence is increasing that the morning convection will lay
out a differential heating boundary from south-central Minnesota
into west-central Wisconsin, but the devil is in the details as
to its strength and position, which will feed into the behavior
of storms later in the afternoon. The 01.00Z HREF guidance is
targeting this boundary for convective initiation around 19-21Z,
though in what form remains less certain. The ARW/NMM cores
have the length of the line initiating in unison and growing
upscale, while the HRRR holds the cap longer and rides more
discrete convection along the boundary--a scenario that would
increase the tornado and hail risk. This aspect of the forecast
remains fluid and likely will remain as such until the midday
hours when we can better assess the environment behind the
morning convection.

No matter how storms form, they will be feeding on a favorable
thermodynamic and kinematic profile with MLCAPE values of
2000-2500 J/kg and somewhat elongated hodographs that would
support organized cell structures. Upscale growth into a bowing
line segment is anticipated, but timing of this transition
remains less certain. The tornado threat looks to continue with
this upscale transition if bowing line segments can reorient
themselves with the 0-3-km shear vector, though we'll have to
see if there is localized backing of the 0-1-km wind field to
further enhance this tornado threat.

In addition to damaging winds--which are the main threat with
the afternoon convection--concerns are increasing about the
possibility for multiple rounds of heavy rainfall in the evening
and overnight. Boundary-parallel mid-level flow coupled with
continued theta-e advection into the initiating front could
result in training cells bringing pockets of 3-6 inches of rain
in short order. In fact, all of the 01.00Z HREF guidance members
have this corridor of higher QPF, but differ in 150 miles on
its location between I-90 in southern Minnesota and I-80 in
central Iowa. Thankfully, antecedent conditions are dry and we
are entering a prime time in which cropland can better absorb
such rains, but obviously such rains in urban locales and
steeper topography could result in flooding.

Thursday - Friday: Severe Storm Risk Continues

The hits keep coming for Thursday and Friday with the lower
tropospheric baroclinic zone wobbling across the region during
this time, but more or less staying across the forecast area.
This will serve as the focus for convective initiation as we go
later in the week, but like a game of dominoes, one small
deviation in storms earlier in the forecast can totally turn the
forecast on its head in a hurry. One thing to watch for
Thursday is how long storms later tonight persist, with a longer
residence time towards morning possibly delaying or shifting
the severe weather threat in the afternoon. Friday faces even
more uncertainty in the timing and hazards with the convection,
but the ingredients are all there, it is just a matter of how
they are mixed.

Holiday Weekend- Early Next Week: Seasonable Temperatures With
Additional Shower/Storm Potential

As the upper level pattern becomes more zonal as we head into
the holiday weekend, several shortwave impulses are depicted to
traverse the mean flow by the deterministic global models. These
waves should result a reprieve from this week's heat as they
usher in cooler air, slightly cooling temperatures towards the
mid 80s, more seasonable for this time of year. Outside of the
more seasonable temperatures, there is the potential for showers
and storms throughout the weekend (40-60%), though these may
shift more to the south depending on how Thursday and Friday's
storms unfold.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 705 AM CDT Wed Jul 1 2026

There will be several rounds of storms through tonight. Like the
01/06z TAFS used the CAMS to try add some timing to them. The
first round will be likely continue through 01/15z. Then there
will likely be scattered supercells this afternoon followed by
widespread convection for late this afternoon and evening.

&&

.CLIMATE...
Issued at 127 AM CDT Wed Jul 1 2026

On June 30, the low temperature at La Crosse Regional Airport was
81F. This surpassed the previous warm low temperature record for
the date of 78F in 1931.

This low temperature was the warmest June low temperature. The
previous record was 80F on June 29, 1931 and June 22, 2025.

It also tied the warmest low temperature ever recorded in La Crosse.
An 81F low temperature has occurred 4 times (July 21, 1901; July
13, 1995; July 4, 2012; and June 30, 2026).

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...Heat Advisory from 1 PM this afternoon to 8 PM CDT this
     evening for WIZ041>044-053>055-061.
MN...Heat Advisory from 1 PM this afternoon to 8 PM CDT this
     evening for MNZ096.
IA...Heat Advisory from 1 PM this afternoon to 8 PM CDT this
     evening for IAZ008>011-018-019-029-030.

&&

DISCUSSION...Falkinham/Skow
AVIATION...Boyne
CLIMATE...Boyne

Hazardous Weather Outlook
National Weather Service La Crosse WI
246 AM CDT Wed Jul 1 2026

IAZ008>011-018-019-029-030-MNZ096-WIZ041>044-053>055-061-021100-
Mitchell-Howard-Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-
Clayton-Houston-La Crosse-Monroe-Juneau-Adams-Vernon-Crawford-
Richland-Grant-
246 AM CDT Wed Jul 1 2026

This Hazardous Weather Outlook is for portions of north central
Iowa...northeast Iowa...southeast Minnesota...central Wisconsin...
southwest Wisconsin and west central Wisconsin.

.DAY ONE...Today and Tonight

...HEAT ADVISORY REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO
8 PM CDT THIS EVENING...

Periodic thunderstorms are expected through tonight. Some of
these storms will become severe. Damaging winds will be the main
threat with these storms, along with large hail and possibly a few
tornadoes.

Heat index values of 95 to 105 degrees this afternoon and
evening.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

The threat for severe thunderstorms continues on Thursday and
possibly into the weekend.

.SPOTTER INFORMATION STATEMENT...

May be needed at times through the weekend.

.EMERGENCY MANAGEMENT COORDINATION...

A webinar is scheduled at 1 pm this afternoon for the severe
weather threat in the afternoon.

MNZ079-086>088-094-095-WIZ017-029-032>034-021100-
Wabasha-Dodge-Olmsted-Winona-Mower-Fillmore-Taylor-Clark-Buffalo-
Trempealeau-Jackson-
246 AM CDT Wed Jul 1 2026

This Hazardous Weather Outlook is for portions of southeast
Minnesota...central Wisconsin...north central Wisconsin and west
central Wisconsin.

.DAY ONE...Today and Tonight

Periodic thunderstorms are expected through tonight. Some of
these storms will become severe. Damaging winds will be the main
threat with these storms, along with large hail and possibly a
few tornadoes.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

The threat for severe thunderstorms continues on Thursday and
possibly into the weekend.

.SPOTTER INFORMATION STATEMENT...

May be needed at times through the weekend.

.EMERGENCY MANAGEMENT COORDINATION...

A webinar is scheduled at 1 pm this afternoon for the severe
weather threat in the afternoon.

Boyne

Preliminary Local Storm Report
National Weather Service La Crosse WI
523 AM CDT Wed Jul 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0441 AM     Tstm Wnd Dmg     5 NNW Readstown         43.51N 90.80W
07/01/2026                   Vernon             WI   Law Enforcement

            Tree fell onto a house. Roof started to
            leaking letting water into the house.

&&

JSB

Preliminary Local Storm Report
National Weather Service La Crosse WI
525 AM CDT Wed Jul 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0444 AM     Tstm Wnd Dmg     6 E Viroqua             43.56N 90.77W
07/01/2026                   Vernon             WI   Law Enforcement

            Tree fell onto a road State Highway 82 near
            Brush Hollow Rd.

&&

JSB

Preliminary Local Storm Report
National Weather Service La Crosse WI
703 AM CDT Wed Jul 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0651 AM     Tstm Wnd Gst     5 WSW Cummingsville     43.84N 92.35W
07/01/2026  M59 MPH          Fillmore           MN   Trained Spotter

&&

APF

Preliminary Local Storm Report
National Weather Service La Crosse WI
704 AM CDT Wed Jul 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0651 AM     Hail             5 WSW Cummingsville     43.84N 92.35W
07/01/2026  E0.70 Inch       Fillmore           MN   Trained Spotter

&&

APF

Special Weather Statement
National Weather Service La Crosse WI
821 AM CDT Wed Jul 1 2026

IAZ009-010-019-MNZ095-011345-
Winneshiek IA-Chickasaw IA-Howard IA-Fillmore MN-
821 AM CDT Wed Jul 1 2026

...STRONG THUNDERSTORMS WILL IMPACT EASTERN HOWARD...NORTHWESTERN
WINNESHIEK...NORTHEASTERN CHICKASAW AND SOUTHEASTERN FILLMORE
COUNTIES THROUGH 845 AM CDT...

At 821 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Lime Springs to near Cresco to near
Jerico. Movement was northeast at 50 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Strong thunderstorms will be near...
  Cresco and Protivin around 825 AM CDT.
  Harmony and Ridgeway around 830 AM CDT.
  Canton around 835 AM CDT.

Other locations impacted by these storms include Vernon Springs
County Park, Choice, Vernon Springs, Hesper, County Roads V 58 And A
46, Bluffton, Locust, Davis Corners, County Roads W 14 And A 34, and
County Roads W 20 And A 34.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4374 9173 4329 9173 4311 9223 4345 9235
TIME...MOT...LOC 1321Z 236DEG 45KT 4345 9222 4332 9216 4317 9222

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

Ferguson