Alert archive / Wisconsin / Tornado Warnings in 2021

Tornado Warning 14, NWS Twin Cities, MN

July 28, 2021Saint Croix County, Wisconsin

NWS Twin Cities, MN issued this tornado warning at Jul 28, 2021, 9:36 PM CDT for Saint Croix County, Wisconsin. It was in force for 24 min. 4 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, 9:36 PM CDT (02:36 UTC)
Expired: Jul 28, 2021, 10:00 PM CDT
In force: 24 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

County Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 92 km from the middle of the area, began a volume at 02:40 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

Time	Report	Where	Remark
Jul 28, 9:48 PM CDT	TORNADO	4 Se New Richmond, WI	TORNADO RATED EF1. PATH LENGTH 5.7 MILES. MAXIMUM WIDTH 100 YARDS. MAXIMUM WINDS ESTIMATED AT 95 MPH. THE TORNADO MOVED SOUTH-SOUTHEAST AND DAMAGED ABOUT ONE DOZEN HOMES INCLUDING ONE WHICH HAD ITS GARAGE BLOWN INTO AN ADJOINING FIELD. THE TORNADO ALSO TORE TH
Jul 28, 9:50 PM CDT	TSTM WND DMG	4 Ssw Deer Park, WI	SURVEY DETERMINED A DOWNBURST HIT THIS AREA. HUNDREDS OF TREES WERE DOWNED OR BROKEN ALONG A BROAD SWATH FROM 4 SSW DEER PARK TO 9 N BALDWIN. VIRTUALLY ALL WERE BLOWN DOWN FROM THE NORTH, NORTHEAST, OR EAST. MANY TREES WERE DOWN ACROSS ROADS AND DRIVEWAYS. THE
Jul 28, 9:50 PM CDT	TSTM WND DMG	5 Nnw Hammond, WI	BARN AND GARAGE TAKEN DOWN, CORN FLATTENED AT COUNTY ROAD E AND 160TH ST. TIME ESTIMATED BY RADAR.
Jul 28, 9:55 PM CDT	HAIL 1.5	New Richmond, WI	PICTURE VIA TWITTER, TIME ESTIMATED VIA 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.

Issued	Product	Office	Lasted
Jul 28, 7:17 PM CDT	Severe Thunderstorm Watch PDS	SPC	7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 2.6 hours before the alert went out and 94 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

434 
WFUS53 KMPX 290236
TORMPX
WIC109-290300-
/O.NEW.KMPX.TO.W.0014.210729T0236Z-210729T0300Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Twin Cities/Chanhassen MN
936 PM CDT Wed Jul 28 2021

The National Weather Service in the Twin Cities has issued a

* Tornado Warning for...
  Central St. Croix County in west central Wisconsin...

* Until 1000 PM CDT.
    
* At 936 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Star Prairie, or 21 miles north of River Falls,
  moving southeast at 45 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur. Tree 
           damage is likely.

* This dangerous storm will be near...
  Baldwin and Hammond around 955 PM CDT.

# 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4521 9261 4521 9250 4504 9218 4497 9245
TIME...MOT...LOC 0236Z 320DEG 38KT 4517 9252 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Dye

1 follow-up statement

053 
WWUS53 KMPX 290246
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
946 PM CDT Wed Jul 28 2021

WIC109-290300-
/O.CON.KMPX.TO.W.0014.000000T0000Z-210729T0300Z/
St. Croix WI-
946 PM CDT Wed Jul 28 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1000 PM CDT FOR CENTRAL
ST. CROIX COUNTY...
    
At 946 PM CDT, a severe thunderstorm capable of producing a tornado
was located near New Richmond, or 18 miles northeast of River Falls,
moving southeast at 45 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur. Tree damage is 
         likely.

This dangerous storm will be near...
  Baldwin and Hammond around 955 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4511 9251 4513 9243 4502 9224 4497 9245
TIME...MOT...LOC 0246Z 320DEG 38KT 4509 9242 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Dye

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 28, 7:19 PM CDT	Special Weather Statement	MPX	Rusk	26 min
Jul 28, 7:37 PM CDT	Severe Thunderstorm Warning	MPX	Rusk	23 min
Jul 28, 7:43 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Polk, Rusk	32 min
Jul 28, 8:01 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Chippewa, Rusk	44 min
Jul 28, 8:09 PM CDT	Tornado Warning	MPX	Polk	35 min
Jul 28, 8:46 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Chippewa, Rusk	59 min
Jul 28, 8:55 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Polk	50 min
Jul 28, 9:08 PM CDT	Tornado Warning	MPX	Chippewa	37 min
Jul 28, 9:25 PM CDT	Severe Thunderstorm Warning	MPX	Dunn, Saint Croix	65 min
Jul 28, 9:30 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Eau Claire	60 min
Jul 28, 9:37 PM CDT	Severe Thunderstorm Warning	MPX	Saint Croix	38 min
Jul 28, 9:55 PM CDT	Tornado Warning	MPX	Saint Croix	35 min
Jul 28, 10:09 PM CDT	Severe Thunderstorm Warning	MPX	Dunn, Pepin, Pierce, Saint Croix	51 min
Jul 28, 10:18 PM CDT	Severe Thunderstorm Warning	MPX	Dunn, Eau Claire, Pepin	42 min
Jul 28, 10:21 PM CDT	Severe Thunderstorm Warning	MPX	Saint Croix	24 min
Jul 28, 10:36 PM CDT	Severe Thunderstorm Warning	MPX	Pepin	39 min
Jul 28, 10:57 PM CDT	Severe Thunderstorm Warning	MPX	Dunn, Pepin, Pierce	48 min

Nearby

Tornado Warnings in Wisconsin, 2021 Every tornado warning in 2021 Tornadoes 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.