Alert archive / Wisconsin / Flash Flood Warnings in 2024

Flash Flood Warning 14, NWS La Crosse, WI

July 15, 2024Grant County, Wisconsin

NWS La Crosse, WI issued this flash flood warning at Jul 15, 2024, 6:45 PM CDT for Grant County, Wisconsin. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 15, 2024, 6:45 PM CDT (23:45 UTC)
Expired
Jul 15, 2024, 9:32 PM CDT
In force
3 hr
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Flood severity
None

County Grant County, WI

The radar

The Quad Cities radar (KDVN), 123 km from the middle of the area, began a volume at 23:47 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.8 hours before the alert went out and 122 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2024-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1844 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2024-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1844 J/kg
Mixed-layer CIN
-134 J/kg
Mixed-layer LCL
967 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
178 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.9

Open this sounding in Storm Lab

The text

As transmitted.

035 
WGUS53 KARX 152345
FFWARX
WIC043-160245-
/O.NEW.KARX.FF.W.0014.240715T2345Z-240716T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service La Crosse WI
645 PM CDT Mon Jul 15 2024

The National Weather Service in La Crosse has issued a

* Flash Flood Warning for...
  Southeastern Grant County in southwestern Wisconsin...

* Until 945 PM CDT.

* At 645 PM CDT, emergency management reported thunderstorms 
  producing heavy rain across the warned area with water over State 
  Highway 80 south of Platteville. Between 1 and 3 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Emergency management reported.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Platteville, Dickeyville, Georgetown, Cornelia, Big Patch and 
  Platteville Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4277 9063 4278 9051 4278 9043 4275 9043
      4268 9043 4261 9043 4262 9064

FLASH FLOOD...OBSERVED

$$

Kurz
2 follow-up statements
034 
WGUS73 KARX 160044
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
744 PM CDT Mon Jul 15 2024

WIC043-160245-
/O.CON.KARX.FF.W.0014.000000T0000Z-240716T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Grant WI-
744 PM CDT Mon Jul 15 2024

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 PM CDT THIS 
EVENING FOR SOUTHEASTERN GRANT COUNTY...

At 744 PM CDT, Emergency management reported thunderstorms producing 
heavy rain across the warned area. Between 1 and 3 inches of rain 
have fallen. Flooding is ongoing.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Emergency management reported.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Platteville, Dickeyville, Georgetown, Cornelia, Big Patch and 
  Platteville Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4277 9063 4278 9051 4278 9043 4275 9043
      4268 9043 4261 9043 4262 9064

FLASH FLOOD...OBSERVED

$$

Shea
011 
WGUS73 KARX 160232
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
932 PM CDT Mon Jul 15 2024

WIC043-160242-
/O.CAN.KARX.FF.W.0014.000000T0000Z-240716T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Grant WI-
932 PM CDT Mon Jul 15 2024

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHEASTERN GRANT COUNTY...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

&&

LAT...LON 4277 9063 4278 9051 4278 9043 4275 9043
      4268 9043 4261 9043 4262 9064

$$

Shea

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS La Crosse, WI wrote its last area forecast discussion before this flash flood warning went out at Jul 15, 2:00 PM CDT, 4 hours 45 minutes earlier. Its key messages:

  • Scattered to areas of storms from late afternoon into early evening. Some will be strong to severe with a damaging wind and hail threat.
  • Turning cooler and less humid for the rest of the week while also trending dry.
Area forecast discussion, Jul 15, 2:00 PM CDT, 4 hours 45 minutes before
Area Forecast Discussion
National Weather Service La Crosse WI
200 PM AM CDT Mon Jul 15 2024

.KEY MESSAGES...

- Scattered to areas of storms from late afternoon into early
evening. Some will be strong to severe with a damaging wind and hail
threat.

- Turning cooler and less humid for the rest of the week while also
trending dry.

&&

.DISCUSSION...
Issued at 200 PM CDT Mon Jul 15 2024

* STORM CHANCES THIS AFTERNOON/TONIGHT - some strong to severe
  possible from late afternoon into early evening

CLouds and showers persisting for the early afternoon, tracking west
to east across southern MN through central WI - working to keep the
local environment relatively stable. Just south of there more sun has
been working on the juicy airmass over IA with the RAP suggesting
3500+ SBCAPE possible over northeast IA by 21z. Bit of shortwave
energy coupled with approaching sfc low and left over outflow
boundary will look to fire convection by mid/late afternoon - but
stout low level cap (per RAP/HRRR bufkit soundings) will keep a lid
on activity before those move in. This could hold off initiation
until after 4 pm. Mostly straight line hodograph in the RAP/HRRR
with 0-6km shear around 40 kts supporting convective updrafts and
some supercellular potential at outset. System could quickly morph
into a convective complex capable of swaths of damaging winds - but
more likely southeast of the local area. Ongoing clouds/showers
provide uncertainty as to northward extent of this particular area
of convection, and this region could change by the hour based on how
the afternoon unfolds. Some HRRR runs keep any significant
convection south/east of the local area. Currently, local severe
threat looks highest for northeast IA and southwest WI in the 4 to 7
pm time frame.

To the north, a cold front with another piece of upper level energy
will be slide cross northern portions of WI. Some clearing there
will increase instability and CAMS models trigger a broken line of
convection (tied to the front) that would drop southeast across the
forecast area. More multicellular with a mixed big of strong/severe
potential outcomes (hail, strong winds). Severe threat is lower with
these storms compared to the anticipated convection over IA.

All the storms would have the potential for locally heavy rain, but
all look to be moving at a good clip with no training of note via
the CAMS. Localized flooding issues could arise, but don't see a
widespread heavy rain/flooding threat that would warrant a Flood
Watch at this time.

* TUESDAY INTO THE WEEKEND - cooler and less humid, trending dry

Another lobe of upper level energy slated to rotate across the upper
mississippi river valley Tue afternoon/evening. Cold air advection a
loft will promote a ribbon of increased low level lapse rates with
perhaps 250-500 J/Kg of MUCAPE. Questions on whether there will be
enough saturation to play with results in mixed signals in the
various short term models (some produce spotty to scattered late
afternoon shower/storms...others don't). With a bit more support for
at least a smattering of light showers, will paint in some low pops
(20%) for the afternoon in a west-east running band, sliding
southward across the region and mostly south of the area by 00z.

Upper level blocking pattern then taking shape for the rest of the
week as ridge continues to amplify/hold firm across the rockies/west
coast while a trough holds over the new england states.

Much cooler and less humid air will flow in from Canada and set up
shop through the upcoming weekend, and could linger well into the
following week. EPS and GEFS members only show a few degree spread
between their 25-75% for highs - mostly topping out in the 70s
through Fri. Probabilities in the LREF start to push to 40-50% to
climb back into the 80s moving into the weekend, but certainly
nothing trending hot & humid.

Meanwhile, the current upper level layout would generally keep most
of the shortwave activity either into Canada or off to the west.
While can't completely rule out some small rain chances here and
there, it's looking like a dry spate of days for most of the region
through the weekend. A welcome break from the recent soggy
conditions.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1236 PM CDT Mon Jul 15 2024

A cold front will approach the area from the NW this afternoon
bringing shower and thunderstorm chances across the area. Due to the
cloud cover this morning, uncertainty continues on if we will see
thunderstorm chances impact LSE or RST directly. Will plan on
amending TAFs as needed for thunderstorms.

Tonight, there is another chance for fog to impact the river valleys
and LSE, but chances for dense fog are around 10 to 20% at this
time. Boundary layer winds look to be strong enough to stave off
widespread fog issues, but fog chances would increase considerably
if skies clear and winds go light until cold front swings through
and brings in drier air.

&&

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

&&

DISCUSSION...Rieck
AVIATION.....JAW
Hazardous weather outlook, Jul 15, 4:00 AM CDT, 14 hours 45 minutes before
Hazardous Weather Outlook
National Weather Service La Crosse WI
400 AM CDT Mon Jul 15 2024

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-161300-
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-
400 AM CDT Mon Jul 15 2024

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

.DAY ONE...Today and Tonight

Thunderstorms are possible today into this evening. A few storms
may become severe, especially late this afternoon or early evening
with damaging winds, locally heavy rain, and hail possible.

Heat indices of 90 to 100 are expected near and south of
Interstate 94 this afternoon.

River rises or flooding continues along some area rivers. Please
see the latest flood statements for additional details.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter groups could be requested later this afternoon.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

In the hours before

Local storm report, Jul 15, 3:10 PM CDT, 3 hours 35 minutes before
Preliminary Local Storm Report
National Weather Service La Crosse WI
310 PM CDT Mon Jul 15 2024

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

0552 PM     Hail             Goodview                44.07N 91.71W
07/13/2024  M2.00 Inch       Winona             MN   Public

0548 PM     Tstm Wnd Dmg     5 E New Rome            44.20N 89.80W
07/13/2024                   Adams              WI   Public

            Numerous trees down in the Lake Arrowhead
            and Lake Sherwood subdivisions.

&&
Special weather statement, Jul 15, 4:34 PM CDT, 2 hours 11 minutes before
Special Weather Statement
National Weather Service La Crosse WI
434 PM CDT Mon Jul 15 2024

IAZ029-152230-
Fayette IA-
434 PM CDT Mon Jul 15 2024

...STRONG THUNDERSTORMS WILL IMPACT SOUTHERN FAYETTE COUNTY THROUGH
530 PM CDT...

At 433 PM CDT, Doppler radar was tracking a cluster of strong
thunderstorms near Fairbank, or near Oelwein, moving east at 30 mph.

HAZARD...Wind gusts up to 30 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...
  Oelwein and Maynard around 440 PM CDT.
  Arlington around 500 PM CDT.

Other locations impacted by this storm include Highway 93 And County
W 14, Highway 93 And County V 68, Volga River State Park, Wadena,
Randalia, Westgate, County Road W 33 And 187, and County Roads 3 And
W 13.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
northeastern Iowa.

&&

LAT...LON 4264 9208 4290 9208 4289 9161 4265 9161
TIME...MOT...LOC 2133Z 273DEG 26KT 4272 9201

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

Rieck
Special weather statement, Jul 15, 5:07 PM CDT, 1 hour 38 minutes before
Special Weather Statement
National Weather Service La Crosse WI
507 PM CDT Mon Jul 15 2024

IAZ029-030-152315-
Clayton IA-Fayette IA-
507 PM CDT Mon Jul 15 2024

...A STRONG THUNDERSTORM WILL IMPACT SOUTHERN CLAYTON AND
SOUTHEASTERN FAYETTE COUNTIES THROUGH 615 PM CDT...

At 506 PM CDT, Doppler radar was tracking a strong thunderstorm near
Lamont, or 13 miles east of Oelwein, moving east at 35 mph.

HAZARD...Wind gusts up to 50 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...
  Strawberry Point around 510 PM CDT.

Other locations impacted by this storm include Camp C.S. Klaus,
Mederville, Highways 3 And 187, Turkey River, Bixby State Park,
Highway 13 And County C 24, Fairview, Osborne, and Millville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
northeastern Iowa...and southwestern Wisconsin.

&&

LAT...LON 4264 9185 4278 9186 4282 9108 4274 9105
      4269 9095 4268 9090 4265 9090
TIME...MOT...LOC 2206Z 266DEG 32KT 4266 9165

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Rieck
Special weather statement, Jul 15, 5:26 PM CDT, 1 hour 19 minutes before
Special Weather Statement
National Weather Service La Crosse WI
526 PM CDT Mon Jul 15 2024

WIZ061-152330-
Grant WI-
526 PM CDT Mon Jul 15 2024

...STRONG THUNDERSTORMS WILL IMPACT SOUTHERN GRANT COUNTY THROUGH 630
PM CDT...

At 525 PM CDT, Doppler radar was tracking a cluster of strong
thunderstorms near Colesburg, or near Guttenberg, moving east at 35
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...
  Cassville around 530 PM CDT.
  Platteville around 615 PM CDT.

Other locations impacted by this storm include Kieler, Lock And Dam
11, Big H Campground, Sandy Hook, Potosi, Beetown, Cornelia,
Rockville, Burton, and Nelson Dewey State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
northeastern Iowa...and southwestern Wisconsin.

&&

LAT...LON 4254 9064 4258 9068 4263 9070 4264 9073
      4269 9097 4274 9104 4274 9105 4281 9108
      4282 9043 4251 9043 4251 9064
TIME...MOT...LOC 2225Z 269DEG 29KT 4269 9111

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

Rieck
Local storm report, Jul 15, 6:16 PM CDT, 29 minutes before
Preliminary Local Storm Report
National Weather Service La Crosse WI
616 PM CDT Mon Jul 15 2024

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

0558 PM     Tstm Wnd Gst     North Buena Vista       42.68N 90.96W
07/15/2024  E75 MPH          Clayton            IA   Law Enforcement

&&
Local storm report, Jul 15, 6:31 PM CDT, 14 minutes before
Preliminary Local Storm Report
National Weather Service La Crosse WI
631 PM CDT Mon Jul 15 2024

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

0628 PM     Tstm Wnd Gst     Hazel Green             42.53N 90.44W
07/15/2024  M72 MPH          Grant              WI   Emergency Mngr

&&

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 14, 8:28 PM CDTRiver Flood WarningARXVernon60 hr
Jul 15, 1:34 PM CDTAreal Flood WarningARXJuneau19 hr
Jul 15, 5:26 PM CDTSpecial Weather StatementARXGrant64 min
Jul 15, 5:50 PM CDTSevere Thunderstorm WarningARXGrant55 min

Nearby

Flash Flood Warnings in Wisconsin, 2024Every flash flood warning in 2024

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.