Alert archive / Iowa / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 8, NWS La Crosse, WI

April 9, 2011Howard County, Winneshiek County, Iowa; Fillmore County, Minnesota

NWS La Crosse, WI issued this severe thunderstorm warning at Apr 9, 2011, 11:15 PM CDT for Howard County, Winneshiek County, Iowa; Fillmore County, Minnesota. It was in force for 45 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
Apr 9, 2011, 11:15 PM CDT (04:15 UTC)
Expired
Apr 10, 2011, 12:00 AM CDT
In force
45 min
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Howard County, IA, Winneshiek County, IA, Fillmore County, MN

The radar

The La Crosse radar (KARX), 94 km from the middle of the area, began a volume at 04:17 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
Apr 9, 7:42 PM CDTSevere Thunderstorm WatchSPC7 hr
Apr 9, 11:01 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 4.3 hours before the alert went out and 189 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 2011-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2011-04-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 355 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
612 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
355 m²/s²
0-3 km storm-relative helicity
550 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.2

Open this sounding in Storm Lab

The text

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

946 
WUUS53 KARX 100415
SVRARX
IAC089-191-MNC045-100500-
/O.NEW.KARX.SV.W.0008.110410T0415Z-110410T0500Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
1115 PM CDT SAT APR 9 2011

THE NATIONAL WEATHER SERVICE IN LA CROSSE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  HOWARD COUNTY IN NORTHEAST IOWA...
  NORTHWESTERN WINNESHIEK COUNTY IN NORTHEAST IOWA...
  SOUTH CENTRAL FILLMORE COUNTY IN SOUTHEAST MINNESOTA...

* UNTIL MIDNIGHT CDT

* AT 1113 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM LOCATED NEAR SARATOGA...OR 17 MILES WEST OF
  CRESCO...MOVING NORTHEAST AT 25 MPH. THIS STORM CAN PRODUCE QUARTER
  SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60 MPH.  

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  HAYDEN PRAIRIE AROUND 1125 PM...
  DAVIS CORNERS AND CHESTER AROUND 1130 PM...
  LIME SPRINGS AROUND 1135 PM...
  BONAIR AND VERNON SPRINGS AROUND 1140 PM...
  CRESCO AND VERNON SPRINGS COUNTY PARK AROUND 1145 PM...
  COUNTY ROADS A 23 AND V 58 AND BRISTOL AROUND 1150 PM...
  GRANGER AROUND 1155 PM...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL AND DAMAGING WINDS. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE
AND STAY AWAY FROM WINDOWS.

A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA. SEVERE
THUNDERSTORMS OCCASIONALLY PRODUCE TORNADOES...AND CAN DO SO QUICKLY.
MOVE INTO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR
BUSINESS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 500 AM SUNDAY MORNING FOR
NORTHEASTERN IOWA AND SOUTHEAST MINNESOTA AND SOUTHWESTERN WISCONSIN.

&&

LAT...LON 4361 9217 4335 9196 4326 9241 4342 9252
TIME...MOT...LOC 0415Z 245DEG 24KT 4336 9243
WIND...HAIL 60MPH 1.00IN

$$

HALBACH
3 follow-up statements
282 
WWUS53 KARX 100427
SVSARX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
1127 PM CDT SAT APR 9 2011

IAC089-191-MNC045-100500-
/O.CON.KARX.SV.W.0008.000000T0000Z-110410T0500Z/
HOWARD IA-WINNESHIEK IA-FILLMORE MN-
1127 PM CDT SAT APR 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTH CENTRAL
FILLMORE...NORTHWESTERN WINNESHIEK AND HOWARD COUNTIES UNTIL MIDNIGHT
CDT...

AT 1122 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM LOCATED NEAR DAVIS CORNERS...OR 9 MILES WEST OF
CRESCO...MOVING NORTHEAST AT 40 MPH. THIS STORM CAN PRODUCE QUARTER
SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  VERNON SPRINGS COUNTY PARK AROUND 1130 PM...
  CRESCO AND COUNTY ROADS A 23 AND V 58 AROUND 1135 PM...
  GRANGER AND STATE ROAD 9 AND 290TH STREET AROUND 1140 PM...
  KENDALLVILLE AND COUNTY ROADS W 14 AND A 34 AROUND 1145 PM...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL AND DAMAGING WINDS. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE
AND STAY AWAY FROM WINDOWS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 500 AM SUNDAY MORNING FOR
NORTHEASTERN IOWA AND SOUTHEAST MINNESOTA AND SOUTHWESTERN WISCONSIN.

&&

LAT...LON 4361 9217 4335 9196 4326 9241 4342 9252
TIME...MOT...LOC 0427Z 247DEG 33KT 4340 9224
WIND...HAIL 60MPH 1.00IN

$$

HALBACH
372 
WWUS53 KARX 100438
SVSARX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
1138 PM CDT SAT APR 9 2011

IAC089-191-MNC045-100500-
/O.CON.KARX.SV.W.0008.000000T0000Z-110410T0500Z/
HOWARD IA-WINNESHIEK IA-FILLMORE MN-
1138 PM CDT SAT APR 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTH CENTRAL
FILLMORE...NORTHWESTERN WINNESHIEK AND NORTHEASTERN HOWARD COUNTIES
UNTIL MIDNIGHT CDT...

AT 1136 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM LOCATED NEAR COUNTY ROADS A 23 AND V 58...OR 6
MILES NORTH OF CRESCO...MOVING NORTHEAST AT 45 MPH. THIS STORM CAN
PRODUCE QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL AND DAMAGING WINDS. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE
AND STAY AWAY FROM WINDOWS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 500 AM SUNDAY MORNING FOR
NORTHEASTERN IOWA AND SOUTHEAST MINNESOTA AND SOUTHWESTERN WISCONSIN.

&&

LAT...LON 4350 9238 4361 9217 4335 9196 4329 9229
TIME...MOT...LOC 0438Z 244DEG 38KT 4347 9211
WIND...HAIL 60MPH 1.00IN

$$

HALBACH
696 
WWUS53 KARX 100451
SVSARX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
1151 PM CDT SAT APR 9 2011

IAC089-191-MNC045-100502-
/O.EXP.KARX.SV.W.0008.000000T0000Z-110410T0500Z/
HOWARD IA-WINNESHIEK IA-FILLMORE MN-
1151 PM CDT SAT APR 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL FILLMORE...
NORTHWESTERN WINNESHIEK AND NORTHEASTERN HOWARD COUNTIES WILL EXPIRE
AT MIDNIGHT CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED AND MOVED OUT OF
THE WARNED AREA.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 500 AM CDT SUNDAY MORNING FOR
NORTHEASTERN IOWA AND SOUTHEAST MINNESOTA AND SOUTHWESTERN WISCONSIN.

LAT...LON 4350 9238 4361 9217 4335 9196 4329 9229
TIME...MOT...LOC 0452Z 244DEG 38KT 4353 9192

$$

HALBACH

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 9, 10:53 PM CDTTornado WarningARXChickasaw, Floyd, Howard, Mitchell37 min
Apr 9, 11:08 PM CDTSevere Thunderstorm WarningARXMitchell52 min
Apr 10, 3:39 PM CDTSevere Thunderstorm WarningARXHoward41 min
Apr 10, 4:11 PM CDTSevere Thunderstorm WarningARXWinneshiek34 min
Apr 10, 5:03 PM CDTSevere Thunderstorm WarningARXAllamakee27 min
Apr 10, 1:44 AM CDTAreal Flood AdvisoryARXFillmore, Houston, Mower, Olmsted, Winona3 hr
Apr 10, 4:24 PM CDTSevere Thunderstorm WarningARXWinona41 min
Apr 10, 4:32 PM CDTTornado WarningARXHouston43 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2011Severe Thunderstorm Warnings in Minnesota, 2011Every severe thunderstorm warning in 2011

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.