Severe Thunderstorm Warning 96, NWS La Crosse, WI

542 
WWUS53 KARX 150007
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
707 PM CDT Sun Jul 14 2024

WIC043-150045-
/O.CON.KARX.SV.W.0096.000000T0000Z-240715T0045Z/
Grant WI-
707 PM CDT Sun Jul 14 2024

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM CDT
FOR EAST CENTRAL GRANT COUNTY...

At 707 PM CDT, a severe thunderstorm was located 7 miles northeast of
Bloomington, or 9 miles northwest of Lancaster, moving south at 10
mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of east
central Grant County, including the following locations... Mount
Hope, Werley, and Mount Ida.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4299 9092 4303 9086 4301 9057 4288 9080
TIME...MOT...LOC 0007Z 348DEG 10KT 4296 9082 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

EMS

202 
WWUS53 KARX 150021
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
721 PM CDT Sun Jul 14 2024

WIC043-150031-
/O.CAN.KARX.SV.W.0096.000000T0000Z-240715T0045Z/
Grant WI-
721 PM CDT Sun Jul 14 2024

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL GRANT COUNTY IS
CANCELLED...

The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been cancelled.

A Severe Thunderstorm Watch remains in effect until 100 AM CDT for
southwestern Wisconsin.

&&

LAT...LON 4299 9092 4303 9086 4301 9057 4288 9080
TIME...MOT...LOC 0019Z 290DEG 10KT 4295 9077 

$$

EMS

Area Forecast Discussion
National Weather Service La Crosse WI
304 PM CDT Sun Jul 14 2024

.KEY MESSAGES...

- Storm chances persist for this evening into Monday evening. A
  few storms may be strong to severe with damaging wind gusts
  and localized flooding being the primary threats primarily on
  Monday. Large hail is a secondary threat.

- Hot and humid conditions continue into Monday with highs in
  the upper 80s to near 90. Widespread heat indices in the lower
  to upper 90s with some areas reaching 100 on Sunday.

- Cooler and drier conditions beginning Tuesday and into much of
  the upcoming week with highs in the middle to upper 70s.

&&

.DISCUSSION...
Issued at 304 PM CDT Sun Jul 14 2024

Humid With Storm Chances This Evening, Some Strong to Severe:

Muggy conditions are the name of the game this afternoon with
observed dewpoints across much of the region well into the 70s. Air
temperatures maintaining into the lower to mid 80s are maybe a touch
cooler than expected with some cloud cover around but still
relatively on track to see highs reach into the upper 80s in
spots by late afternoon and early evening with heat indices in
the middle to upper 90s in some locales.

As we head into the evening hours, our convective environment is
essentially a powder keg with guidance showing the potential for the
cap to erode across southern portions of our area during the evening
hours (shown in the KDBQ 14.13z RAP sounding at 6pm). When
considering MLCAPE values of 2000-3000 J/kg across our south would
expect storms to initiate very quickly with anything that provide
any kick in the atmosphere. Looking at GOES-16 water vapor imagery,
a remnant MCV can be noted across western and central MN that
is slowly trekking southeast accompanied with a subtle
shortwave. As a result, many of the CAMs rapidly develop a
cluster of storms across portions of northeast IA and
southwestern WI later this evening. Currently, the main question
with this is the aforementioned cap which tries to erode with
this weak forcing. How much the cap erodes will determine
convective coverage. Shear profiles appear fairly weak with
0-6km shear in the 14.16z RAP being fairly minimal, around 20-30
kts. As a result, would expecting a more multi-cell
configuration with individual cells struggling to maintain.
Consequently, would only expect to see hail with more robust
updrafts. However, with fairly robust DCAPE values collocated
with the MCV, would think that cores could collapse fairly
vigorously which could lead to isolated downburst gusts to 60
mph. Storms will quickly exit the region to the southeast with
the window for storms being likely a few hours (through about
8-9pm at the latest).

Severe Weather Potential Early Monday into Monday Evening:

As we head into the overnight, forecast soundings show in the 14.16z
RAP has low-level saturation and fairly light winds throughout
the low-levels. Consequently, with much of the recent rainfall
we have seen over the past few days, could see areas of fog
initially during the overnight, with questions remaining as for
how long it maintains as an incoming MCV approaches. As this MCV
and accompanying 500mb shortwave approaches, expecting to see
convection as it approaches the local area during the morning
hours. As it then progresses eastward a surface cold front is
draped across our region and pushes south with additional
convective initiation possible. As a result, with severe regimes
in play for Monday several different scenarios may be possible.

Starting with the morning MCV, as the shortwave moves through
the local area (Which also still maintains some uncertainty in
timing amongst deterministic guidance) during the morning hours,
modest MLCAPE of 2000-3000 J/kg would certainly provide enough
of a boost to get convection going. However, deterministic
soundings (14.15z RAP) would suggest a cap is still largely in
place during the morning hours which would be a serious
hindrance to convection as noted in the 14.12z HRRR which has
storms fizzling out as they approach the local area. However, if
storms can form an organized cold pool with the higher
effective bulk shear in the vicinity of the MCV. This type of
convective complex (as illustrated in the 14.12z ARW) would
likely pose some damaging wind threat if it can utilize the
instability gradient and get through the cap.

As we head into afternoon, the aforementioned cold front pushes
through the region during the afternoon. The key question as we
approach this time of day is how the cap will behave, the CAMs
vary considerably on this with the 14.12z HRRR keeping the cap
in place throughout the day leading to minimal convective
development as the front progresses through. This is contrasted
heavily by the most aggressive solution in the 14.12z ARW which
would favor an organized MCS along the boundary pushing south
with relatively uncapped thermodynamics and plenty of 0-3km
shear (roughly 35-50 kts in the 14.15z RAP) for forward
propagation and potential bowing structures. As a result, if
this scenario were to manifest would expect damaging winds to be
the primary threat with heavy rainfall potentially leading to
flash flooding concerns where soils are already very saturated.
Consequently, the SPC has a slight risk (Threat level 2 of 5)
across much of the local area.

The last caveat to this whole forecast is an organized MCS across
central IA that some of the recent CAMs have been trying to pick up
on. While much of the CAMs mainly keep it south of the area through
the afternoon and evening hours, fairly favorable 0-3km shear
profiles and MLCAPE of 3000-5000 J/kg in the 14.15z RAP would enable
a bow echo type structure to push east with the potential for
damaging wind gusts (perhaps approaching 70-80 mph).
Furthermore, this is highlighted in the 14.12z HRRR neural
network probabilities which has modest probabilities (40-50%)
for winds over 50 kts across portions of northeastern IA. With
some uncertainty in exactly where the MCS positions itself the
SPC has put extreme southern portions of our forecast area
across northeast Iowa and southwestern WI in an Enhanced risk
(Threat level 3 of 5) to address this potential. However, many
questions remain such has how any prior convection's outflow
could affect the environment and available instability for this
MCS. As a result, will be very important to stay tuned to
upcoming forecast updates as mesoscale details become more fine
tuned.

Regardless, if storms materialize will want to watch the heavy rain
potential as well with precipitable waters of around 2" and fairly
respectable warm cloud depths (around 3.5 km in the 14.12 NAM)
which would lead to some efficient rainfall makers. While the
14.12z EC/GEFS ensemble generally only has medium probabilities
(30-60% chance) or over 0.5" through Monday night, the 14.12z
HREF ensemble max paints spots of 2-3" over the next 48 hours
which would suggest areas that receive repeat rounds of storms
could see locally heavy rainfall amounts. As a result, when
considering prior rainfall from yesterday of anywhere 2-5"
leading to saturated soils, localized flash flooding may be
possible.

Cooler and Dry Pattern Begins Tuesday:

Going into Tuesday, a broad scale synoptic trough pivots its way
into our region, aiding in the shove cold air advection further
south resulting in a cooling trend through the middle of next week.
As a result, the 14.00z grand ensemble (GEFS/EC ensemble/Canadian
ensemble) with an inter-quartile range of highs at La Crosse
for Wednesday of 71 to 76 with a median of 74. Median
temperatures in the grand ensemble generally trend in the middle
70s to lower 80s. Additionally, with increasing subsidence with
surface high pressure building in mid-week, would expect
minimal precipitation chances through Friday.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1240 PM CDT Sun Jul 14 2024

VFR conditions are expected to prevail through this TAF period.
There is a high-level stratus ceiling moving from west to east
into the local area from a dying thunderstorm complex early this
AM across Iowa. This remnant thunderstorm complex is expected to
bring a chance (30 to 50%) for afternoon thunderstorms along
and south of Interstate 90 this afternoon between 20 and 24Z,
but these chances are not expected to impact LSE or RST.

As the boundary layer decouples tonight, there is a 20% chance
for river valley fog to develop at LSE, but will hold off on
putting in TAF at this time due to uncertainty in development.

&&

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

&&

DISCUSSION...Naylor
AVIATION...JAW

Hazardous Weather Outlook
National Weather Service La Crosse WI
155 PM CDT Sun Jul 14 2024

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-152300-
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-
155 PM CDT Sun Jul 14 2024

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

.DAY ONE...Today and Tonight

Thunderstorms chances return this evening and late tonight with a
few strong storms possible.

Afternoon heat indices of 90 to 100 are expected.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

Thunderstorm chances continue into Monday. Some of the storms
could become strong to severe.

Afternoon heat indices of 90 to 100 are expected.

.SPOTTER INFORMATION STATEMENT...

Spotters may be needed Monday.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

nofwd

Special Weather Statement
National Weather Service La Crosse WI
507 PM CDT Sun Jul 14 2024

WIZ055-142300-
Richland WI-
507 PM CDT Sun Jul 14 2024

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL RICHLAND COUNTY THROUGH
600 PM CDT...

At 505 PM CDT, Doppler radar was tracking a strong thunderstorm 8
miles west of Richland Center, moving east at 25 mph.

HAZARD...Wind gusts up to 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Richland Center, Excelsior, Ithaca, Boaz, Eagle Cave, Loyd, Tavera,
Sextonville, Neptune, Buck Creek, Gotham, Keyesville, and Twin
Bluffs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4325 9066 4339 9066 4348 9019 4320 9019
TIME...MOT...LOC 2205Z 265DEG 21KT 4332 9056

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

EMS

Special Weather Statement
National Weather Service La Crosse WI
558 PM CDT Sun Jul 14 2024

WIZ061-142330-
Grant WI-
558 PM CDT Sun Jul 14 2024

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL GRANT COUNTY
THROUGH 630 PM CDT...

At 557 PM CDT, Doppler radar was tracking a strong thunderstorm near
Platteville, moving east at 15 mph.

HAZARD...Wind gusts up to 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

This strong thunderstorm will be near...
  Platteville around 605 PM CDT.

Other locations impacted by this storm include Arthur, Union,
Ellenboro, and Platteville Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 100 AM CDT for
southwestern Wisconsin.

&&

LAT...LON 4270 9064 4284 9066 4288 9043 4269 9043
TIME...MOT...LOC 2257Z 257DEG 13KT 4278 9050

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

EMS

Special Weather Statement
National Weather Service La Crosse WI
617 PM CDT Sun Jul 14 2024

IAZ008>011-018-019-029-030-WIZ053>055-061-150100-
Mitchell-Howard-Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-
Clayton-Vernon-Crawford-Richland-Grant-
Including the cities of Osage, Cresco, Decorah, Waukon,
Charles City, New Hampton, Oelwein, Elkader, Viroqua,
Prairie Du Chien, Richland Center, and Platteville
617 PM CDT Sun Jul 14 2024

...FUNNEL CLOUDS POSSIBLE THIS EVENING...

WHAT...Funnel clouds are possible through early this evening.
These funnel clouds are typically brief, drop only a few hundred
feet from the cloud base, and rarely become a tornado or cause
damage.

WHERE...Northeast Iowa and southwest Wisconsin.

WHEN...Until 8pm.

IMPACTS...None expected.

PREPAREDNESS AND PRECAUTIONARY ACTIONS...If a funnel cloud is spotted,
report it to the National Weather Service. If a tornado warning
becomes necessary, take appropriate action.

A Severe Thunderstorm Watch remains in effect until 100 AM CDT for
southwestern Wisconsin.

&&

LAT...LON 4270 9064 4284 9066 4288 9043 4269 9043
TIME...MOT...LOC 2257Z 257DEG 13KT 4278 9050

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Boyne

Special Weather Statement
National Weather Service La Crosse WI
623 PM CDT Sun Jul 14 2024

WIZ054-055-061-150000-
Richland WI-Crawford WI-Grant WI-
623 PM CDT Sun Jul 14 2024

...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN GRANT...
SOUTHWESTERN RICHLAND AND SOUTHEASTERN CRAWFORD COUNTIES THROUGH 700
PM CDT...

At 623 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles southwest of Boscobel, or 16 miles east of Prairie Du Chien,
moving east at 25 mph.

HAZARD...Wind gusts up to 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

This strong thunderstorm will be near...
  Boscobel around 630 PM CDT.

Other locations impacted by this storm include Westport, Wauzeka,
Preston, Highway 61 And County T, Werley, Mount Ida, Harris Ridge,
Highways 60 And 61, Port Andrew, and County Roads K And T.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 100 AM CDT for
southwestern Wisconsin.

&&

LAT...LON 4301 9099 4311 9098 4326 9056 4293 9054
TIME...MOT...LOC 2323Z 271DEG 22KT 4309 9081

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

EMS