River Flood Warning 6, NWS La Crosse, WI

Area Forecast Discussion
National Weather Service La Crosse WI
647 PM CDT Wed Apr 23 2025

.KEY MESSAGES...

- Periodic chances of showers and storms are on tap through
  Friday. Some storms could become strong to severe this
  evening, with large hail being the main threat, and locally
  damaging winds as a lesser, secondary threat.

- There is a low risk of localized flooding due to heavy
  rainfall possible Thursday night. Total rainfall amounts
  through Friday are expected to range between 0.5" to 1.5",
  heaviest over southeast MN and northeast IA.

- A strong trough could bring another risk of severe weather and
  heavy rainfall to the region next Monday and Tuesday, along
  with seasonably warm temperatures in the 70s.

&&

.DISCUSSION...
Issued at 303 PM CDT Wed Apr 23 2025

We will continue to see periodic chances of showers and
thunderstorms through the day Friday, with the most likely chances
coming Thursday night (70 to 90%). Before Thursday night, zonal flow
aloft should provide only weak forcing for ascent overall. However,
we are keeping an eye on a cold front that will sweep through the
area late this afternoon into the evening hours. There could be
enough instability to spark off some storms during this time. The
threat for strong to severe storms remains pretty marginal, given
MUCAPE values to around 500 to 1000 J/kg per the 23.12z HREF
ensemble, with mid-level lapse rates progged around 6 to 7 C/km.
This would support the threat for large hail. Locally strong wind
gusts appear to be more of a secondary threat with any strong storms
as there is a brief window of time before the boundary layer
decouples and stabilizes the lower levels. SPC has maintained a
Marginal Risk (level 1 of 5) for severe weather this evening for
areas along and south of a line from Osage, IA to Monroe Center, WI.

As we go into the day Thursday, the zonal flow aloft will gradually
breakdown, making way for a mid-level impulse to sweep through the
Upper MS Valley region Thursday night into Friday morning.
Increasing chances (70-90+%) of mainly showers are expected with
this wave, given meager instability and mid-level lapse rates.
However, the main focus for Thursday night will be heavier downpours
due to copious moisture. Pwat values between 1 to 1.4" are progged
with this activity, which is above the 90th percentile on the EC
ensemble percentiles for precipitable water. The bulk of the
precipitation for tonight through Friday should come during this
time. Total rainfall should range between 0.5" to 1.5", but some
locally higher amounts to around 2" are possible, per the HREF LPMM
QPF fields.

Eventually, conditions will dry out Friday, thanks to an area of
high pressure that will build out of the Canadian Prairies. This
should result in a seasonal Saturday, with high temperatures warming
to the lower 60s across the area and dry conditions under mostly
sunny skies. Sunday appears to be mostly dry to start, although
shortwave ridging could spark off some more showers and perhaps an
isolated thunderstorms later in the day.

As we look ahead towards the start of the work week, we continue to
keep an eye on an increased threat for strong to severe storms over
the Upper MS Valley as a longwave upper-level trough approaches the
region. An attendant cold front will eventually move through the
area by late Monday, which should support some likely chances (50-
70%) of showers and storms. The convective parameter space appears
supportive of the potential for strong to severe convection, given
MLCAPE values on the order of 1000-2000 J/kg, and deep-layer shear
values of 40 to 50 knots. ECMWF EFI values for CAPE-Shear are
leaning towards values of 0.6 to 0.7 - on the lower-end of the
scale. However, the CSU-ML severe probabilities suggest a notable
signal for severe weather, with an all-hazards scenario possible.
For now, SPC has outlooked the entire forecast area in a Slight Risk
(level 2 of 5) for severe weather late Monday, so stay tuned to the
latest forecast! It will also feel warmer by Monday, with high
temperatures building into the middle to upper 70s for most
locations.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 645 PM CDT Wed Apr 23 2025

VFR conditions currently present across the area. Isolated
showers and thunderstorms are currently moving east across the
area north of I-90 with the most intense activity east of the
Mississippi River. Convective activity will be fairly limited
across the area with coverage in showers and storms increasing a
bit more overnight into tomorrow morning. Have covered these
chances with PROB30s at the terminals for now but these may need
to be adjusted in future updates. Late in the period looks to
be when coverage becomes more widespread. Any showers and storms
could create brief MVFR conditions with lower CIGs and
visibilities. RST will also see MVFR CIGs begin to build in
late in the period with IFR to LIFR possible after 00Z.

&&

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

&&

DISCUSSION...Zapotocny
AVIATION...Barendse

Hazardous Weather Outlook
National Weather Service La Crosse WI
421 AM CDT Wed Apr 23 2025

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ029-032>034-
041>044-053>055-061-241330-
Mitchell-Howard-Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-
Clayton-Wabasha-Dodge-Olmsted-Winona-Mower-Fillmore-Houston-Clark-
Buffalo-Trempealeau-Jackson-La Crosse-Monroe-Juneau-Adams-Vernon-
Crawford-Richland-Grant-
421 AM CDT Wed Apr 23 2025

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

Periodic showers and thunderstorms today and tonight. An isolated
strong to severe storm could develop over parts of northeast Iowa
or southwest Wisconsin. Large hail would be the primary severe
risk with a secondary risk of damaging winds.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

There is a chance for thunderstorms Thursday and Thursday night.
At this time, severe storms are not anticipated.

Thunderstorms return to the forecast Sunday through Tuesday. It is
too early to determine the severe weather risk.

.SPOTTER INFORMATION STATEMENT...

While spotter activation may not be utilized today, any severe
weather reports would be appreciated.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

WIZ017-241330-
Taylor-
421 AM CDT Wed Apr 23 2025

This Hazardous Weather Outlook is for portions of north central
Wisconsin.

.DAY ONE...Today and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Thunderstorms return to the forecast Sunday through Tuesday. It is
too early to determine the severe weather risk.

.SPOTTER INFORMATION STATEMENT...

No action needed.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

Zapotocny

Special Weather Statement
National Weather Service La Crosse WI
626 PM CDT Wed Apr 23 2025

WIZ041-042-240000-
La Crosse WI-Monroe WI-
626 PM CDT Wed Apr 23 2025

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL LA CROSSE AND
SOUTHWESTERN MONROE COUNTIES THROUGH 700 PM CDT...

At 626 PM CDT, Doppler radar was tracking a strong thunderstorm over
Bangor, or 9 miles southwest of Sparta, moving east at 30 mph.

HAZARD...Half inch hail.

SOURCE...Radar indicated.

IMPACT...Minor hail damage to vegetation is possible.

This storm will remain over mainly rural areas of east central La
Crosse and southwestern Monroe Counties, including the following
locations... Leon, Farmers Valley, and The Coulee Experimental
Forest.

This includes Interstate 90 in Wisconsin between mile markers 16 and
19.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4383 9108 4388 9109 4393 9064 4381 9064
TIME...MOT...LOC 2326Z 265DEG 26KT 4387 9097

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...<30 MPH

Ferguson

Special Weather Statement
National Weather Service La Crosse WI
701 PM CDT Wed Apr 23 2025

WIZ043-044-240045-
Juneau WI-Adams WI-
701 PM CDT Wed Apr 23 2025

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL JUNEAU AND CENTRAL ADAMS
COUNTIES THROUGH 745 PM CDT...

At 700 PM CDT, Doppler radar was tracking a strong thunderstorm over
Dellwood, or 7 miles west of Friendship, moving east at 35 mph.

HAZARD...Half inch hail.

SOURCE...Radar indicated.

IMPACT...Minor hail damage to vegetation is possible.

This strong thunderstorm will be near...
  Adams and Friendship around 705 PM CDT.

Other locations impacted by this storm include Kens Marina And
Campground, Highway 13 And County E, Buckhorn State Park, The Preston
Cliffs, Grand Marsh, County Roads G And M, Roche A Cri State Park,
and Highway 21 And County G.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4392 9007 4400 9006 4402 8960 4388 8960
TIME...MOT...LOC 0000Z 272DEG 29KT 4394 8997

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...<30 MPH

Ferguson