Severe Thunderstorm Warning 164, NWS La Crosse, WI

Area Forecast Discussion
National Weather Service La Crosse WI
111 PM CDT Fri Aug 7 2026

.KEY MESSAGES...

- Severe storm risk this afternoon remains a lower confidence
  forecast owing to early morning storms. Pockets of damaging
  winds and heavy rain would be the main threats, which look to
  be focusing over south-central MN and north-central IA.

- Additional rounds of storms return to the forecast from early
  Sunday morning through midweek. There may exist a severe
  weather threat with these storms, but confidence in such
  details is low at this time.

- Seasonal temperatures continue for the weekend with a slight
  cooling trend by midweek as the storm risk pushes south.

&&

.DISCUSSION...
Issued at 110 PM CDT Fri Aug 7 2026

This Afternoon: Storm Details

Several rounds of storms have developed since sunrise on the
nose of a 850-700-mb theta-e ridge that is advancing eastward
just ahead of a surface cold front bifurcating Minnesota from
SW to NE. As expected, the complex hodographs and linear
forcing, coupled with a narrow instability axis in which storms
have little residence time, have resulted in transient storm
structures and a rapid upscale growth. The southern side of the
line has become the dominant feature as of 18Z and is making the
southeastward turn as the cold pool becomes established. This
trend will continue over the next few hours, with damaging winds
being the main threat.

Additional storms may form along the nose the the theta-e ridge,
but time is running out for this to occur before the cold front
arrives. The cold front may serve as a source for additional
convective initiation, but there has been ample anvil shading
along the front and any risk for these storms may be displaced
further north towards northern Wisconsin.

Sunday Morning: Next Round of Storms, Heavy Rain Threat?

Cooler and more stable air filters southward tonight in the wake of
the cold front and persists for much of Saturday as the front stalls
and pivots near I-80 in Iowa. Lee cyclogenesis along the Front Range
helps push this (now warm) front northward across the region once
again late Saturday night into Sunday morning. Aided by a 30-40 kt
LLJ, these storms could be more robust in nature and produce heavy
rainfall. While confidence is increasing that there will be some
sort of MCS across the region, the devil is in the details as to
when exactly it will form, which will dictate its track. Aided by
increasing Gulf moisture and PWATs of 1.5 to 2 inches, coupled with
an increasing line parallel storm motion, this complex could put
down efficient rainfall rates in short order and will need to be
monitored for any flooding risk.

Early Next Week: Continued Storm Risk

The lower tropospheric front stalls between central Iowa and
southern Minnesota for later Sunday through Tuesday, presenting
multiple windows of opportunities for convection that could
bring heavy rain. However, details of these storms remain very
nebulous and will be refined over the coming days.

Mid to Late Week: Drier and Cooler

The medium to longer range solutions are in general agreement
that a a polar airmass will build southward through mid to late
week as the surface baroclinic zone sags southward. This should
result in cooler and drier weather, though with the surface
front not far away, it will not take much of a wobble in the
forecast to bring this rain back northward.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1200 PM CDT Fri Aug 7 2026

Primary concern over the next 24 hours is the likelihood (60%)
for TS to move west to east across the area this afternoon and
evening, affecting both LSE/RST. Have maintained previous TAF
posture of TS mentions with TEMPO groups of IFR visibility but
with timing adjustments. After TS departs to the east,
northwesterly winds should be predominant and should (80%)
serve to keep stratus/fog concerns confined to the Wisconsin
River valley around OVS overnight into Saturday morning.

&&

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

&&

DISCUSSION...Skow
AVIATION...Ferguson

Hazardous Weather Outlook
National Weather Service La Crosse WI
908 AM CDT Fri Aug 7 2026

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-081815-
Mitchell-Howard-Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-
Clayton-Wabasha-Dodge-Olmsted-Winona-Mower-Fillmore-Houston-
Taylor-Clark-Buffalo-Trempealeau-Jackson-La Crosse-Monroe-Juneau-
Adams-Vernon-Crawford-Richland-Grant-
908 AM CDT Fri Aug 7 2026

This Hazardous Weather Outlook is for portions of northeast Iowa.

.DAY ONE...Today and Tonight

Strong storms are possible this afternoon and evening with
damaging winds (15% chance) as the main hazard.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Additional rounds of storms are possible on Sunday and into early
next week, some of which may approach severe levels and produce
heavy rain.

.SPOTTER INFORMATION STATEMENT...

No action needed.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

KDS