Alert archive / Wisconsin / Areal Flood Advisories in 2021

Areal Flood Advisory 12, NWS La Crosse, WI

August 7, 2021La Crosse County, Trempealeau County, Wisconsin; Winona County, Minnesota

NWS La Crosse, WI issued this areal flood advisory at Aug 7, 2021, 2:23 PM CDT for La Crosse County, Trempealeau County, Wisconsin; Winona County, Minnesota. It was in force for 112 min.

The area

The counties it named.

The facts

Issued
Aug 7, 2021, 2:23 PM CDT (19:23 UTC)
Expired
Aug 7, 2021, 4:15 PM CDT
In force
112 min
Issued by
NWS La Crosse, WI
Area
Storm-based polygon

Counties Winona County, MN, La Crosse County, WI, Trempealeau County, WI

The radar

The La Crosse radar (KARX), 33 km from the middle of the area, began a volume at 19:23 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.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 7.4 hours before the alert went out and 282 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 2021-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1645 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 2021-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 39 square meters per square second.193958Sfc1 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
1645 J/kg
Mixed-layer CIN
-79 J/kg
Mixed-layer LCL
1006 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
39 m²/s²
0-3 km storm-relative helicity
37 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood advisory 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 areal flood advisory went out at Aug 7, 12:04 PM CDT, 2 hours 19 minutes earlier.

Area forecast discussion, Aug 7, 12:04 PM CDT, 2 hours 19 minutes before
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Hazardous weather outlook, Aug 7, 2:49 AM CDT, 11 hours 34 minutes before
Hazardous Weather Outlook
National Weather Service La Crosse WI
249 AM CDT Sat Aug 7 2021

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-081200-
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-
249 AM CDT Sat Aug 7 2021

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

.DAY ONE...Today and Tonight

Periods of thunderstorms are likely through tonight with a few
severe storms possible. The main hazards will be large hail,
damaging winds and torrential rainfall. An isolated tornado is
also possible. Localized flooding could occur if storms repeat
over the same area.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Additional thunderstorms are expected Sunday into Sunday night. A
few storms could produce strong winds and hail. Any storms also
will be capable of producing torrential rainfall.

Periodic thunderstorm chances will continue for most of next week.
At this time it is too early to discern any severe weather threat.

.SPOTTER INFORMATION STATEMENT...

Spotter reports may be needed at times this weekend.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

In the hours before

Special weather statement, Aug 7, 12:12 PM CDT, 2 hours 11 minutes before
Special Weather Statement
National Weather Service La Crosse WI
1212 PM CDT Sat Aug 7 2021

MNZ079-071730-
Wabasha MN-
1212 PM CDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of central Wabasha
County through 1230 PM CDT...

At 1211 PM CDT, Doppler radar was tracking a strong thunderstorm 9
miles north of Elgin, or 15 miles southwest of Wabasha, moving
northeast at 35 mph.

HAZARD...Penny size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

Locations impacted include...
West Albany, Bremen, Zumbro Falls, Millville, Hammond, Jarrett,
Zumbro Bottoms Campground, Conception, County Roads 18 And 4, County
Roads 33 And 4, Dumfries, Theilman, Kruger Campground and County
Roads 31 And 2.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4431 9244 4442 9212 4441 9211 4423 9201
      4420 9239
TIME...MOT...LOC 1711Z 245DEG 29KT 4426 9232

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...<30 MPH

Skow
Special weather statement, Aug 7, 12:19 PM CDT, 2 hours 4 minutes before
Special Weather Statement
National Weather Service La Crosse WI
1219 PM CDT Sat Aug 7 2021

WIZ055-071745-
Richland WI-
1219 PM CDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of central Richland
County through 1245 PM CDT...

At 1219 PM CDT, Doppler radar was tracking a strong thunderstorm 9
miles west of Richland Center, moving northeast at 25 mph.

HAZARD...Half inch hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

Locations impacted include...
Richland Center, Rockbridge, Sylvan, Boaz, Yuba, County Roads D And N
N, Sabin, Highways 58 And 154, Woodstock, Gillingham, Bloom City,
Neptune, Buck Creek, County Roads A And Z, Five Points, Bosstown,
County Roads Z Z And Q, Hub City, Highways 80 And 56 and Ash Ridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4337 9021 4329 9061 4342 9067 4355 9048
      4355 9041
TIME...MOT...LOC 1719Z 237DEG 20KT 4338 9056

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

Skow
Special weather statement, Aug 7, 12:23 PM CDT, 2 hours before
Special Weather Statement
National Weather Service La Crosse WI
1223 PM CDT Sat Aug 7 2021

MNZ087-088-071800-
Olmsted MN-Winona MN-
1223 PM CDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of western Winona and
southeastern Olmsted Counties through 100 PM CDT...

At 1223 PM CDT, Doppler radar was tracking a strong thunderstorm near
Eyota, or 7 miles southeast of Rochester, moving east at 45 mph.

HAZARD...Penny size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

Locations impacted include...
Rochester, Stewartville, St. Charles, Eyota, Dover, Marion, Viola,
Elba, Chester, Whitewater State Park, and Predmore.

This includes Interstate 90 in Minnesota between mile markers 210 and
238.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4403 9248 4411 9217 4411 9208 4413 9208
      4416 9197 4389 9197 4387 9249
TIME...MOT...LOC 1723Z 253DEG 38KT 4397 9234

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...<30 MPH

Skow
Local storm report, Aug 7, 1:37 PM CDT, 46 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LA CROSSE WI
137 PM CDT SAT AUG 7 2021

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

0135 PM     FLOOD            GOODVIEW                44.07N 91.71W
08/07/2021                   WINONA             MN   EMERGENCY MNGR

            STREET FLOODING OCCURRING IN GOODVIEW AND
            THE WEST SIDE OF WINONA.

&&
Special weather statement, Aug 7, 1:48 PM CDT, 35 minutes before
Special Weather Statement
National Weather Service La Crosse WI
148 PM CDT Sat Aug 7 2021

MNZ088-WIZ032-033-041-071915-
Winona MN-Buffalo WI-Trempealeau WI-La Crosse WI-
148 PM CDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of southeastern Winona,
southeastern Buffalo, northwestern La Crosse and southern Trempealeau
Counties through 215 PM CDT...

At 147 PM CDT, Doppler radar was tracking a strong thunderstorm near
Trempealeau, or near Winona, moving east at 30 mph.

HAZARD...Wind gusts up to 50 mph and nickel size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
La Crosse, Winona, Onalaska, Holmen, Trempealeau, Galesville, Dakota,
French Island, La Crosse Airport, Brice Prairie, Medary, New
Hartford, and Dresbach.

This includes the following highways...
 Interstate 90 in Minnesota between mile markers 254 and 276.
 Interstate 90 in Wisconsin between mile markers 1 and 5.

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.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4411 9163 4407 9110 4382 9122 4383 9128
      4385 9129 4385 9137 4390 9168
TIME...MOT...LOC 1847Z 279DEG 26KT 4401 9155

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...50 MPH

Skow
Special weather statement, Aug 7, 2:14 PM CDT, 9 minutes before
Special Weather Statement
National Weather Service La Crosse WI
214 PM CDT Sat Aug 7 2021

WIZ041-042-071945-
La Crosse WI-Monroe WI-
214 PM CDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of eastern La Crosse
and southwestern Monroe Counties through 245 PM CDT...

At 213 PM CDT, Doppler radar was tracking a strong thunderstorm over
Holmen, or 8 miles north of La Crescent, moving east at 30 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 damage to outdoor objects is
         possible.

Locations impacted include...
La Crosse, Sparta, Onalaska, West Salem, Bangor, Leon, Burns, and
Rockland.

This includes Interstate 90 in Wisconsin between mile markers 6 and
26.

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.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4382 9122 4407 9111 4406 9074 4375 9086
TIME...MOT...LOC 1913Z 285DEG 27KT 4395 9127

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

Skow

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 6:26 AM CDTSpecial Weather StatementARXBuffalo34 min
Aug 7, 7:40 AM CDTSpecial Weather StatementARXLa Crosse35 min
Aug 7, 9:17 AM CDTSpecial Weather StatementARXJuneau28 min
Aug 7, 10:12 AM CDTSpecial Weather StatementARXAdams33 min
Aug 7, 11:17 AM CDTSpecial Weather StatementARXCrawford28 min
Aug 7, 11:24 AM CDTSevere Thunderstorm WarningARXLa Crosse, Vernon27 min
Aug 7, 11:26 AM CDTSevere Thunderstorm WarningARXCrawford, Richland, Vernon21 min
Aug 7, 12:19 PM CDTSpecial Weather StatementARXRichland26 min
Aug 7, 12:59 PM CDTAreal Flood AdvisoryARXBuffalo2 hr
Aug 7, 1:17 PM CDTSevere Thunderstorm WarningARXRichland, Vernon58 min
Aug 7, 1:48 PM CDTSpecial Weather StatementARXLa Crosse27 min
Aug 7, 2:14 PM CDTSpecial Weather StatementARXLa Crosse31 min
Aug 7, 3:02 PM CDTRiver Flood WarningARXMonroe, Vernon21 days
Aug 7, 3:02 PM CDTRiver Flood WarningARXVernon4 days
Aug 7, 3:02 PM CDTRiver Flood WarningARXRichland, Vernon4 days
Aug 7, 3:02 PM CDTRiver Flood WarningARXRichland, Vernon61 hr
Aug 7, 3:02 PM CDTRiver Flood WarningARXBuffalo, Trempealeau19 hr
Aug 7, 3:07 PM CDTAreal Flood AdvisoryARXLa Crosse74 min
Aug 7, 3:17 PM CDTSpecial Weather StatementARXVernon73 min
Aug 7, 3:23 PM CDTFlash Flood WarningARXLa Crosse, Monroe3 hr
Aug 7, 3:35 PM CDTSevere Thunderstorm WarningARXVernon55 min
Aug 7, 3:52 PM CDTSevere Thunderstorm WarningARXCrawford38 min
Aug 7, 4:00 PM CDTTornado WarningARXCrawford30 min
Aug 7, 4:05 PM CDTSevere Thunderstorm WarningARXRichland40 min
Aug 7, 4:19 PM CDTTornado WarningARXCrawford, Grant41 min
Aug 7, 4:27 PM CDTFlash Flood WarningARXVernon3 hr
Aug 7, 4:56 PM CDTTornado Warning Tornado observedARXGrant19 min
Aug 7, 5:53 PM CDTSevere Thunderstorm WarningARXJuneau, Monroe, Vernon37 min
Aug 7, 6:18 PM CDTFlash Flood WatchARXAdams, Buffalo, Clark, Crawford, Jackson, Juneau and 5 more35 hr
Aug 7, 7:21 AM CDTSpecial Weather StatementARXWinona24 min
Aug 7, 10:29 AM CDTSpecial Weather StatementARXOlmsted31 min
Aug 7, 10:33 AM CDTSevere Thunderstorm WarningARXDodge, Olmsted, Wabasha42 min
Aug 7, 11:14 AM CDTSpecial Weather StatementARXWabasha31 min
Aug 7, 12:12 PM CDTSpecial Weather StatementARXWabasha18 min
Aug 7, 12:23 PM CDTSpecial Weather StatementARXOlmsted37 min

Nearby

Areal Flood Advisories in Wisconsin, 2021Areal Flood Advisories in Minnesota, 2021Every areal flood advisory in 2021

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.