Alert archive / Iowa / Tornado Warnings in 2021

Tornado Warning 42, NWS Des Moines, IA

December 15, 20215 counties in Iowa

NWS Des Moines, IA issued this tornado warning at Dec 15, 2021, 5:18 PM CST for 5 counties in Iowa. It was in force for 42 min. 5 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, 5:18 PM CST (23:18 UTC)
Expired
Dec 15, 2021, 6:00 PM CST
In force
42 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Tornado
Observed
Hail
0.75 in

Counties Adair County, IA, Boone County, IA, Dallas County, IA, Greene County, IA, Guthrie County, IA

The radar

The Des Moines radar (KDMX), 55 km from the middle of the area, began a volume at 23:19 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, 5:25 PM CSTTSTM WND GST 734 Ne Guthrie Center, IA
Dec 15, 5:32 PM CSTTSTM WND DMGYale, IAREPORT OF AN OUTBUILDING DESTROYED.
Dec 15, 5:39 PM CSTTSTM WND DMGGrand Junction, IAPUBLIC RELAYED SIDING MISSING ON HOUSE ON SE SIDE OF GRAND JUNCTION. TIME ESTIMATED FROM RADAR.
Dec 15, 5:41 PM CSTTSTM WND GST 70Perry, IA60 TO 70 MPH WIND GUST REPORTS FROM AMATEUR RADIO OPERATORS IN PERRY.
Dec 15, 5:45 PM CSTTSTM WND GST 743 Ese Dawson, IADIALED INTO PERRY AWOS.

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, 1:23 PM CSTTornado WatchSPC7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.3 hours before the alert went out and 172 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, Omaha, NE at 12:00Z on 2021-12-15Temperature 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, Omaha, NE at 12:00Z on 2021-12-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 346 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
2165 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
346 m²/s²
0-3 km storm-relative helicity
384 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

958 
WFUS53 KDMX 152318
TORDMX
IAC001-015-049-073-077-160000-
/O.NEW.KDMX.TO.W.0042.211215T2318Z-211216T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
518 PM CST Wed Dec 15 2021

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Southeastern Greene County in west central Iowa...
  Central Guthrie County in west central Iowa...
  Southwestern Boone County in central Iowa...
  Northwestern Dallas County in central Iowa...
  Northwestern Adair County in southwestern Iowa...

* Until 600 PM CST.
    
* At 518 PM CST, a tornado producing storm was located 7 miles
  northwest of Guthrie Center, moving northeast at 85 mph.

  HAZARD...Damaging tornado.

  SOURCE...Radar confirmed tornado.

  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
  southeastern Greene, central Guthrie, southwestern Boone,
  northwestern Dallas and northwestern Adair Counties, including the
  following locations... Dawson, Rippey, Perry Municipal Airport,
  Grand Junction, Yale, Beaver, Berkley, Jamaica, Springbrook State
  Park and Lakin Slough Game Management Area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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 4150 9455 4168 9470 4212 9421 4192 9391
TIME...MOT...LOC 2318Z 215DEG 74KT 4175 9459 

TORNADO...OBSERVED
MAX HAIL SIZE...<.75 IN

$$

Martin
1 follow-up statement
956 
WWUS53 KDMX 152333
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
533 PM CST Wed Dec 15 2021

IAC001-152343-
/O.CAN.KDMX.TO.W.0042.000000T0000Z-211216T0000Z/
Adair IA-
533 PM CST Wed Dec 15 2021

...THE TORNADO WARNING FOR NORTHWESTERN ADAIR COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 800 PM CST for central and
west central Iowa.

LAT...LON 4161 9438 4176 9461 4212 9421 4192 9391
TIME...MOT...LOC 2333Z 224DEG 64KT 4192 9433 

$$

IAC015-049-073-077-160000-
/O.CON.KDMX.TO.W.0042.000000T0000Z-211216T0000Z/
Greene IA-Guthrie IA-Boone IA-Dallas IA-
533 PM CST Wed Dec 15 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 PM CST FOR
SOUTHEASTERN GREENE...NORTHEASTERN GUTHRIE...SOUTHWESTERN BOONE AND
NORTHWESTERN DALLAS COUNTIES...
        
At 533 PM CST, a confirmed tornado was located 7 miles south of
Jefferson, moving northeast at 75 mph.

HAZARD...Damaging tornado.

SOURCE...Radar confirmed tornado.

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...
Perry, Guthrie Center, Panora, Lake Panorama, Grand Junction, Bagley,
Rippey, Yale, Jamaica, Dawson, Bouton, Beaver, Berkley, Perry
Municipal Airport, Lakin Slough Game Management Area and Springbrook
State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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 4161 9438 4176 9461 4212 9421 4192 9391
TIME...MOT...LOC 2333Z 224DEG 64KT 4192 9433 

TORNADO...OBSERVED
MAX HAIL SIZE...<.75 IN

$$

Martin

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 15, 4:13 PM CSTSevere Thunderstorm Warning Destructive damage threatDMXAdair, Adams, Audubon, Cass, Guthrie, Ringgold and 2 more77 min
Dec 15, 4:16 PM CSTSevere Thunderstorm Warning Destructive damage threatDMXCarroll, Crawford, Sac74 min
Dec 15, 4:37 PM CSTTornado Warning Tornado observedDMXCass23 min
Dec 15, 4:44 PM CSTTornado WarningDMXCrawford36 min
Dec 15, 4:53 PM CSTTornado WarningDMXAdair, Audubon, Cass, Guthrie33 min
Dec 15, 5:07 PM CSTTornado WarningDMXSac27 min
Dec 15, 5:10 PM CSTSevere Thunderstorm Warning Destructive damage threatDMXAdair, Audubon, Boone, Dallas, Greene, Guthrie and 4 more80 min
Dec 15, 5:10 PM CSTTornado WarningDMXCarroll, Crawford35 min
Dec 15, 5:14 PM CSTTornado WarningDMXAudubon, Calhoun, Carroll, Greene, Guthrie31 min
Dec 15, 5:15 PM CSTTornado WarningDMXCalhoun, Carroll, Crawford, Sac30 min
Dec 15, 5:19 PM CSTSevere Thunderstorm Warning Destructive damage threatDMXBoone, Calhoun, Carroll, Emmet, Greene, Humboldt and 5 more71 min
Dec 15, 5:22 PM CSTSevere Thunderstorm Warning Destructive damage threatDMXCarroll, Crawford, Sac23 min
Dec 15, 5:22 PM CSTSevere Thunderstorm Warning Considerable damage threatDMXAdair, Adams, Clarke, Decatur, Madison, Ringgold and 3 more68 min
Dec 15, 5:36 PM CSTTornado WarningDMXCalhoun, Humboldt, Kossuth, Palo Alto, Pocahontas24 min
Dec 15, 5:38 PM CSTTornado Warning Tornado observedDMXBoone, Calhoun, Greene, Hamilton, Webster37 min
Dec 15, 5:45 PM CSTTornado WarningDMXCalhoun, Pocahontas, Webster30 min
Dec 15, 5:52 PM CSTSevere Thunderstorm Warning Destructive damage threatDMXBoone, Franklin, Hamilton, Hancock, Hardin, Humboldt and 6 more53 min
Dec 15, 5:58 PM CSTTornado WarningDMXHancock, Humboldt, Kossuth, Palo Alto, Pocahontas32 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.