Alert archive / Wisconsin / Tornado Warnings in 2009

Tornado Warning 44, NWS Twin Cities, MN

August 19, 2009Dunn County, Saint Croix County, Wisconsin

NWS Twin Cities, MN issued this tornado warning at Aug 19, 2009, 4:04 PM CDT for Dunn County, Saint Croix County, Wisconsin. It was in force for 26 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
Aug 19, 2009, 4:04 PM CDT (21:04 UTC)
Expired
Aug 19, 2009, 4:30 PM CDT
In force
26 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon

Counties Dunn County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 110 km from the middle of the area, began a volume at 21:07 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
Aug 19, 4:11 PM CDTTORNADOForest, WITORNADO ON GROUND AT HWY 64 AT HWY 63 INTERSECTION.
Aug 19, 4:15 PM CDTTORNADO2 N Forest, WITORNADO STILL ON GROUND AT INTERSECTION OF 270TH STR. AND 20TH AVE.

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

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 9.1 hours before the alert went out and 113 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 12:00Z on 2009-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 368 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, Minneapolis, MN at 12:00Z on 2009-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 121 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
368 J/kg
Mixed-layer CIN
-49 J/kg
Mixed-layer LCL
615 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
121 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.2
Supercell composite
3.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WFUS53 KMPX 192104
TORMPX
WIC033-109-192130-
/O.NEW.KMPX.TO.W.0044.090819T2104Z-090819T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
404 PM CDT WED AUG 19 2009

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN ST. CROIX COUNTY IN WEST CENTRAL WISCONSIN...
  NORTHWESTERN DUNN COUNTY IN WEST CENTRAL WISCONSIN...

* UNTIL 430 PM CDT

* AT 404 PM CDT...LAW ENFORCEMENT REPORTED A TORNADO 1 MILE 
  WEST OF EMERALD. RADAR SHOWED THE TORNADIC STORM MOVING NORTH      
  AT 30 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
  GLENWOOD CITY...
  EMERALD...
  CYLON...
  FOREST...
  CONNORSVILLE...
  DOWNING...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 4521 9231 4521 9199 4500 9212 4505 9238
TIME...MOT...LOC 2104Z 201DEG 27KT 4506 9223

$$
1 follow-up statement
000 
WWUS53 KMPX 192113
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
413 PM CDT WED AUG 19 2009

WIC033-109-192130-
/O.CON.KMPX.TO.W.0044.000000T0000Z-090819T2130Z/
ST. CROIX WI-DUNN WI-
413 PM CDT WED AUG 19 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 430 PM CDT FOR
NORTHWESTERN DUNN AND NORTHEASTERN ST. CROIX COUNTIES...

AT 410 PM CDT...A TORNADO WAS REPORTED BY LAW ENFORCEMENT NEAR 
FOREST.

AT 413 PM CDT...RADAR CONTINUED TO INDICATE A SEVERE THUNDERSTORM
CAPABLE OF PRODUCING A TORNADO.  THE MOST DANGEROUS PART OF THE STORM
WAS LOCATED 3 MILES EAST OF FOREST...AND MOVING NORTH AT 30 MPH.

LOCATIONS IN THE WARNING INCLUDE...
CONNORSVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 4521 9231 4521 9199 4500 9212 4505 9238
TIME...MOT...LOC 2113Z 201DEG 27KT 4512 9220

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 2:43 PM CDTTornado WarningMPXPierce32 min
Aug 19, 2:53 PM CDTTornado WarningMPXSaint Croix22 min
Aug 19, 2:57 PM CDTTornado WarningMPXPierce, Saint Croix48 min
Aug 19, 3:16 PM CDTTornado WarningMPXPolk, Saint Croix29 min
Aug 19, 4:06 PM CDTTornado WarningMPXPierce, Saint Croix39 min
Aug 19, 4:14 PM CDTTornado WarningMPXBarron, Polk46 min
Aug 19, 4:21 PM CDTTornado WarningMPXPolk39 min
Aug 19, 4:33 PM CDTTornado WarningMPXSaint Croix27 min
Aug 19, 4:43 PM CDTTornado WarningMPXDunn, Pierce, Saint Croix47 min
Aug 19, 5:13 PM CDTTornado WarningMPXBarron, Dunn, Polk, Saint Croix47 min

Nearby

Tornado Warnings in Wisconsin, 2009Every tornado warning in 2009Tornadoes in 2009

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.