Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 94, NWS La Crosse, WI

August 27, 2021Clayton County, Iowa; Crawford County, Grant County, Wisconsin

NWS La Crosse, WI issued this severe thunderstorm warning at Aug 27, 2021, 8:03 PM CDT for Clayton County, Iowa; Crawford County, Grant County, Wisconsin. It was in force for 42 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 27, 2021, 8:03 PM CDT (01:03 UTC)
Expired
Aug 27, 2021, 8:45 PM CDT
In force
42 min
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

Counties Clayton County, IA, Crawford County, WI, Grant County, WI

The radar

The La Crosse radar (KARX), 99 km from the middle of the area, began a volume at 01:08 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 27, 5:15 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.1 hours before the alert went out and 154 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 00:00Z on 2021-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 995 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2021-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.1939Sfc1 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
995 J/kg
Mixed-layer CIN
-68 J/kg
Mixed-layer LCL
1707 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3

Open this sounding in Storm Lab

The text

As transmitted.

027 
WUUS53 KARX 280103
SVRARX
IAC043-WIC023-043-280145-
/O.NEW.KARX.SV.W.0094.210828T0103Z-210828T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service La Crosse WI
803 PM CDT Fri Aug 27 2021

The National Weather Service in La Crosse has issued a

* Severe Thunderstorm Warning for...
  North central Clayton County in northeastern Iowa...
  West central Grant County in southwestern Wisconsin...
  Southwestern Crawford County in southwestern Wisconsin...

* Until 845 PM CDT.

* At 802 PM CDT, a severe thunderstorm was located near McGregor, or
  near Prairie Du Chien, moving east at 30 mph.

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

  SOURCE...Trained weather spotters.

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

* Locations impacted include...
  Prairie Du Chien, McGregor, Bloomington, Marquette, Bridgeport,
  Beetown, Mount Ida, Bagley, and Mount Hope.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

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

&&

LAT...LON 4294 9130 4309 9117 4300 9067 4274 9080
TIME...MOT...LOC 0102Z 289DEG 25KT 4301 9126 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH

$$

Skow

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 27, 7:04 PM CDTAreal Flood AdvisoryARXChickasaw, Howard116 min
Aug 27, 7:29 PM CDTSevere Thunderstorm WarningARXAllamakee, Clayton, Winneshiek46 min
Aug 27, 7:38 PM CDTFlash Flood WatchARXAllamakee, Chickasaw, Clayton, Fayette, Floyd, Howard and 2 more18 hr
Aug 27, 8:09 PM CDTSevere Thunderstorm WarningARXMitchell25 min
Aug 27, 8:45 PM CDTFlash Flood WarningARXHoward, Mitchell9 hr
Aug 27, 10:26 PM CDTSpecial Weather StatementARXChickasaw, Howard, Winneshiek34 min
Aug 27, 11:07 PM CDTSpecial Weather StatementARXWinneshiek23 min
Aug 27, 11:12 PM CDTFlash Flood WarningARXChickasaw, Floyd6 hr
Aug 28, 1:16 AM CDTFlash Flood WarningARXFayette, Winneshiek4 hr
Aug 28, 3:00 AM CDTSpecial Weather StatementARXClayton30 min
Aug 28, 3:06 AM CDTRiver Flood WarningARXClayton3 days
Aug 28, 3:06 AM CDTRiver Flood WarningARXClayton3 days
Aug 28, 4:05 AM CDTRiver Flood WarningARXFloyd70 hr
Aug 28, 9:39 AM CDTAreal Flood WarningARXChickasaw, Fayette, Floyd, Howard, Mitchell, Winneshiek30 hr
Aug 27, 8:48 PM CDTSevere Thunderstorm WarningARXGrant42 min
Aug 27, 8:59 PM CDTTornado WarningARXGrant31 min
Aug 27, 11:24 PM CDTSpecial Weather StatementARXVernon36 min
Aug 27, 11:31 PM CDTSevere Thunderstorm WarningARXRichland, Vernon59 min
Aug 27, 11:41 PM CDTFlash Flood WarningARXVernon4 hr
Aug 27, 11:53 PM CDTSevere Thunderstorm WarningARXRichland37 min
Aug 28, 1:40 AM CDTSevere Thunderstorm WarningARXCrawford, Richland49 min
Aug 28, 3:15 AM CDTRiver Flood WarningARXLa Crosse, Trempealeau5 days
Aug 28, 4:14 AM CDTRiver Flood WarningARXVernon31 hr
Aug 28, 10:24 AM CDTRiver Flood WarningARXCrawford4 days
Aug 28, 10:38 AM CDTRiver Flood WatchARXJuneau22 hr
Aug 28, 10:46 AM CDTRiver Flood WatchARXCrawford23 hr

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2021Severe Thunderstorm Warnings in Iowa, 2021Every severe thunderstorm warning 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.