Alert archive / Iowa / Tornado Warnings in 2021

Tornado Warning 21, NWS La Crosse, WI

December 15, 2021Floyd County, Iowa

NWS La Crosse, WI issued this tornado warning at Dec 15, 2021, 6:44 PM CST for Floyd County, Iowa. It was in force for 32 min. 7 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
Dec 15, 2021, 6:44 PM CST (00:44 UTC)
Expired
Dec 15, 2021, 7:16 PM CST
In force
32 min
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

County Floyd County, IA

The radar

The La Crosse radar (KARX), 159 km from the middle of the area, began a volume at 00:46 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
Dec 15, 7:00 PM CSTTSTM WND DMG1 E Rudd, IAROOF ON HWY 27 NEAR PARK ENTRANCE.
Dec 15, 7:00 PM CSTTSTM WND DMG5 Nne Marble Rock, IANUMEROUS REPORTS OF WIND DAMAGE TO HOUSES.
Dec 15, 7:00 PM CSTTSTM WND DMGFloyd, IAOVERTURNED SEMI-TRUCK TRAILER AT TRUCK STOP.
Dec 15, 7:09 PM CSTHAIL 1Charles City, IANICKEL TO QUARTER SIZED HAIL REPORTED.
Dec 15, 7:15 PM CSTTSTM WND DMGRudd, IADAMAGE TO RAILROAD TRACKS.
Dec 15, 7:15 PM CSTTSTM WND GST 552 E Charles City, IA
Dec 15, 7:15 PM CSTTSTM WND GST 553 E Charles City, IAAWOS STATION KCCY CHARLES CITY AIRPORT.

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
Dec 15, 5:30 PM CSTTornado WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 0.7 hours before the alert went out and 208 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 2021-12-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 633 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 00:00Z on 2021-12-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 443 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
633 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
770 m above ground
0-6 km bulk shear
75 kt
0-1 km storm-relative helicity
443 m²/s²
0-3 km storm-relative helicity
470 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.7

Open this sounding in Storm Lab

The text

As transmitted.

590 
WFUS53 KARX 160044
TORARX
IAC067-160130-
/O.NEW.KARX.TO.W.0021.211216T0044Z-211216T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service La Crosse WI
644 PM CST Wed Dec 15 2021

The National Weather Service in La Crosse has issued a

* Tornado Warning for...
  Floyd County in north central Iowa...

* Until 730 PM CST.

* At 643 PM CST, severe thunderstorms capable of producing both
  tornadoes and extensive straight line wind damage were located 7
  miles east of Hampton, moving northeast at 85 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.

* These dangerous storms will be near...
  Rockford and Marble Rock around 655 PM CST.
  Rudd around 700 PM CST.
  Charles City and Floyd around 705 PM CST.

Other locations impacted by this tornadic thunderstorm include
Colwell County Park, Highway 14 And County Road B 60, County Roads B
60 And T 18, Idlewilde State Park, Roseville, Howardville and County
Roads 147 And T 34.

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 4305 9303 4321 9298 4321 9256 4306 9256
      4291 9276 4291 9303
TIME...MOT...LOC 0043Z 210DEG 72KT 4278 9306 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...1.00 IN

$$

Baumgardt
4 follow-up statements
877 
WWUS53 KARX 160054
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
654 PM CST Wed Dec 15 2021

IAC067-160130-
/O.CON.KARX.TO.W.0021.000000T0000Z-211216T0130Z/
Floyd IA-
654 PM CST Wed Dec 15 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM CST FOR FLOYD
COUNTY...

At 653 PM CST, a severe squall line capable of producing both
tornadoes and extensive straight line wind damage was located over
Marble Rock, or 14 miles southwest of Charles City, moving northeast
at 85 mph.

HAZARD...Tornado.

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.

These dangerous storms will be near...
  Rudd around 700 PM CST.
  Charles City and Floyd around 705 PM CST.

Other locations impacted by this tornadic thunderstorm include
Colwell County Park, Highway 14 And County Road B 60, County Roads B
60 And T 18, Idlewilde State Park, Roseville, Howardville and County
Roads 147 And T 34.

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 4305 9303 4321 9298 4321 9256 4306 9256
      4291 9276 4291 9303
TIME...MOT...LOC 0053Z 210DEG 72KT 4296 9292 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Baumgardt
869 
WWUS53 KARX 160102
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
702 PM CST Wed Dec 15 2021

IAC067-160130-
/O.CON.KARX.TO.W.0021.000000T0000Z-211216T0130Z/
Floyd IA-
702 PM CST Wed Dec 15 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM CST FOR FLOYD
COUNTY...

At 701 PM CST, a severe squall line capable of producing both
tornadoes and extensive straight line wind damage was located near
Floyd, or 7 miles northwest of Charles City, moving northeast at 85
mph.

HAZARD...Tornado.

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 tornadic thunderstorm will remain over mainly rural areas of
Floyd County, including the following locations... Colwell County
Park, Highway 14 And County Road B 60, Idlewilde State Park,
Roseville, Howardville.

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 4304 9301 4321 9298 4321 9256 4306 9256
      4291 9276 4298 9290
TIME...MOT...LOC 0101Z 210DEG 72KT 4311 9280 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Baumgardt
351 
WWUS53 KARX 160110
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
710 PM CST Wed Dec 15 2021

IAC067-160130-
/O.CON.KARX.TO.W.0021.000000T0000Z-211216T0130Z/
Floyd IA-
710 PM CST Wed Dec 15 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM CST FOR
NORTHEASTERN FLOYD COUNTY...

At 710 PM CST, a severe squall line capable of producing both
tornadoes and extensive straight line wind damage was located near
Osage, moving northeast at 75 mph.

HAZARD...Tornado.

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.

Locations impacted include...
Charles City, Floyd, Colwell, Colwell County Park, Idlewilde State
Park, Howardville, County Roads B 20 And T 26 and Floyd Crossing.

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 4316 9289 4321 9298 4321 9256 4306 9256
      4299 9266 4308 9277
TIME...MOT...LOC 0110Z 210DEG 67KT 4323 9270 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Baumgardt
760 
WWUS53 KARX 160116
SVSARX

Severe Weather Statement
National Weather Service La Crosse WI
716 PM CST Wed Dec 15 2021

IAC067-160126-
/O.CAN.KARX.TO.W.0021.000000T0000Z-211216T0130Z/
Floyd IA-
716 PM CST Wed Dec 15 2021

...THE TORNADO WARNING FOR NORTHEASTERN FLOYD COUNTY IS CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 1100 PM CST for north central
Iowa.

LAT...LON 4316 9289 4321 9298 4321 9256 4306 9256
      4299 9266 4308 9277
TIME...MOT...LOC 0114Z 210DEG 72KT 4334 9262 

$$

Baumgardt

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 15, 6:37 PM CSTSevere Thunderstorm Warning Considerable damage threatARXChickasaw, Floyd, Howard, Mitchell68 min
Dec 15, 7:25 PM CSTTornado WarningARXHoward20 min
Dec 15, 7:29 PM CSTSevere Thunderstorm Warning Considerable damage threatARXAllamakee, Clayton, Fayette, Winneshiek61 min
Dec 15, 7:38 PM CSTTornado WarningARXWinneshiek37 min
Dec 15, 8:16 PM CSTSevere Thunderstorm Warning Considerable damage threatARXAllamakee, Clayton74 min
Dec 15, 8:29 PM CSTSevere Thunderstorm Warning Considerable damage threatARXAllamakee, Clayton31 min

Nearby

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