Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 64, NWS Twin Cities, MN

July 28, 2021Chippewa County, Eau Claire County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 28, 2021, 9:30 PM CDT for Chippewa County, Eau Claire County, Wisconsin. It was in force for 60 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 28, 2021, 9:30 PM CDT (02:30 UTC)
Expired
Jul 28, 2021, 10:30 PM CDT
In force
60 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
70.0 mph

Counties Chippewa County, WI, Eau Claire County, WI

The radar

The La Crosse radar (KARX), 104 km from the middle of the area, began a volume at 02:34 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.

What was reported inside it

TimeReportWhereRemark
Jul 28, 9:40 PM CDTTSTM WND DMG9 S Boyd, WI8-10 INCH DIAMATER TREES DOWN IN TOWN OF WILSON, RELAYED TO NWS THROUGH EAU CO COMMS. TIME ESTIMATED BY RADAR.
Jul 28, 10:05 PM CDTTSTM WND DMGFairchild, WI8-10 INCH DIAMETER TREES DOWN IN FAIRCHILD. RELAYED TO NWS THROUGH EAU COUNTY COMMS. TIME ESTIMATED BY RADAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

IssuedProductOfficeLasted
Jul 28, 7:17 PM CDTSevere Thunderstorm Watch PDSSPC7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 2.5 hours before the alert went out and 198 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, Minneapolis, MN at 00:00Z on 2021-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4815 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, Minneapolis, MN at 00:00Z on 2021-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 374 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
4815 J/kg
Mixed-layer CIN
-38 J/kg
Mixed-layer LCL
1185 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
374 m²/s²
0-3 km storm-relative helicity
461 m²/s²
Significant tornado parameter
8.9
Supercell composite
48.1

Open this sounding in Storm Lab

The text

As transmitted.

809 
WUUS53 KMPX 290230
SVRMPX
WIC017-035-290330-
/O.NEW.KMPX.SV.W.0064.210729T0230Z-210729T0330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
930 PM CDT Wed Jul 28 2021

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Southern Chippewa County in west central Wisconsin...
  Eastern Eau Claire County in west central Wisconsin...

* Until 1030 PM CDT.

* At 929 PM CDT, a severe thunderstorm was located near Cadott, or 12
  miles northeast of Eau Claire, moving southeast at 35 mph.

  HAZARD...70 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect considerable 
           tree damage. Wind damage is also likely to mobile homes, 
           roofs, and outbuildings.

* This severe thunderstorm will be near...
  Boyd around 940 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4460 9112 4502 9156 4499 9092 4470 9092
      4460 9093
TIME...MOT...LOC 0229Z 314DEG 31KT 4495 9122 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...70MPH
 
$$

Dye

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 28, 7:19 PM CDTSpecial Weather StatementMPXRusk26 min
Jul 28, 7:37 PM CDTSevere Thunderstorm WarningMPXRusk23 min
Jul 28, 7:43 PM CDTSevere Thunderstorm WarningMPXBarron, Polk, Rusk32 min
Jul 28, 8:01 PM CDTSevere Thunderstorm WarningMPXBarron, Chippewa, Rusk44 min
Jul 28, 8:09 PM CDTTornado WarningMPXPolk35 min
Jul 28, 8:46 PM CDTSevere Thunderstorm WarningMPXBarron, Chippewa, Rusk59 min
Jul 28, 8:55 PM CDTSevere Thunderstorm WarningMPXBarron, Polk50 min
Jul 28, 9:08 PM CDTTornado WarningMPXChippewa37 min
Jul 28, 9:25 PM CDTSevere Thunderstorm WarningMPXDunn, Saint Croix65 min
Jul 28, 9:36 PM CDTTornado WarningMPXSaint Croix24 min
Jul 28, 9:37 PM CDTSevere Thunderstorm WarningMPXSaint Croix38 min
Jul 28, 9:55 PM CDTTornado WarningMPXSaint Croix35 min
Jul 28, 10:09 PM CDTSevere Thunderstorm WarningMPXDunn, Pepin, Pierce, Saint Croix51 min
Jul 28, 10:18 PM CDTSevere Thunderstorm WarningMPXDunn, Eau Claire, Pepin42 min
Jul 28, 10:21 PM CDTSevere Thunderstorm WarningMPXSaint Croix24 min
Jul 28, 10:36 PM CDTSevere Thunderstorm WarningMPXPepin39 min
Jul 28, 10:57 PM CDTSevere Thunderstorm WarningMPXDunn, Pepin, Pierce48 min

Nearby

Severe Thunderstorm Warnings in Wisconsin, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.