Alert archive / Iowa / Tornado Warnings in 2021

Tornado Warning 36, NWS Des Moines, IA

December 15, 2021Crawford County, Iowa

NWS Des Moines, IA issued this tornado warning at Dec 15, 2021, 4:44 PM CST for Crawford County, Iowa. It was in force for 36 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: Dec 15, 2021, 4:44 PM CST (22:44 UTC)
Expired: Dec 15, 2021, 5:20 PM CST
In force: 36 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Crawford County, IA

The radar

The Omaha radar (KOAX), 102 km from the middle of the area, began a volume at 22:48 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.

Issued	Product	Office	Lasted
Dec 15, 1:23 PM CST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 10.7 hours before the alert went out and 102 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: 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.

169 
WFUS53 KDMX 152244
TORDMX
IAC047-152330-
/O.NEW.KDMX.TO.W.0036.211215T2244Z-211215T2330Z/

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

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Central Crawford County in west central Iowa...

* Until 530 PM CST.
    
* At 444 PM CST, a severe thunderstorm capable of producing a tornado
  was located near Dunlap, or 16 miles southwest of Denison, moving
  northeast at 60 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 dangerous storm will be near...
  Denison around 500 PM CST.

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 4198 9567 4221 9546 4221 9510 4186 9555
      4186 9562 4187 9567
TIME...MOT...LOC 2244Z 225DEG 54KT 4190 9564 

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

$$

Cogil

3 follow-up statements

466 
WWUS53 KDMX 152251
SVSDMX

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

IAC047-152330-
/O.CON.KDMX.TO.W.0036.000000T0000Z-211215T2330Z/
Crawford IA-
451 PM CST Wed Dec 15 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 530 PM CST FOR CENTRAL
CRAWFORD COUNTY...
        
At 451 PM CST, a confirmed tornado was located 8 miles north of
Dunlap, or 9 miles west of Denison, moving northeast at 60 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 tornado will be near...
  Denison around 500 PM CST.

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 4198 9567 4221 9546 4221 9510 4186 9555
      4186 9562 4187 9567
TIME...MOT...LOC 2251Z 225DEG 54KT 4198 9554 

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

$$

Cogil

396 
WWUS53 KDMX 152256
SVSDMX

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

IAC047-152330-
/O.CON.KDMX.TO.W.0036.000000T0000Z-211215T2330Z/
Crawford IA-
456 PM CST Wed Dec 15 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 530 PM CST FOR NORTHERN
CRAWFORD COUNTY...
        
At 455 PM CST, a confirmed tornado was located 7 miles northwest of
Denison, moving northeast at 65 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
northern Crawford County, including the following locations... Kiron,
Deloit, Schleswig and Charter Oak.

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 4221 9546 4221 9510 4196 9543 4201 9564
TIME...MOT...LOC 2255Z 215DEG 58KT 4208 9546 

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

$$

Cogil

817 
WWUS53 KDMX 152320
SVSDMX

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

IAC047-152329-
/O.CAN.KDMX.TO.W.0036.000000T0000Z-211215T2330Z/
Crawford IA-
520 PM CST Wed Dec 15 2021

...THE TORNADO WARNING FOR NORTHERN CRAWFORD 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 800 PM CST for west central
Iowa.

LAT...LON 4221 9546 4221 9510 4196 9543 4201 9564
TIME...MOT...LOC 2319Z 225DEG 54KT 4234 9510 

$$

Cogil

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 15, 4:13 PM CST	Severe Thunderstorm Warning Destructive damage threat	DMX	Adair, Adams, Audubon, Cass, Guthrie, Ringgold and 2 more	77 min
Dec 15, 4:16 PM CST	Severe Thunderstorm Warning Destructive damage threat	DMX	Carroll, Crawford, Sac	74 min
Dec 15, 4:37 PM CST	Tornado Warning Tornado observed	DMX	Cass	23 min
Dec 15, 4:53 PM CST	Tornado Warning	DMX	Adair, Audubon, Cass, Guthrie	33 min
Dec 15, 5:07 PM CST	Tornado Warning	DMX	Sac	27 min
Dec 15, 5:10 PM CST	Severe Thunderstorm Warning Destructive damage threat	DMX	Adair, Audubon, Boone, Dallas, Greene, Guthrie and 4 more	80 min
Dec 15, 5:10 PM CST	Tornado Warning	DMX	Carroll, Crawford	35 min
Dec 15, 5:14 PM CST	Tornado Warning	DMX	Audubon, Calhoun, Carroll, Greene, Guthrie	31 min
Dec 15, 5:15 PM CST	Tornado Warning	DMX	Calhoun, Carroll, Crawford, Sac	30 min
Dec 15, 5:18 PM CST	Tornado Warning Tornado observed	DMX	Adair, Boone, Dallas, Greene, Guthrie	42 min
Dec 15, 5:19 PM CST	Severe Thunderstorm Warning Destructive damage threat	DMX	Boone, Calhoun, Carroll, Emmet, Greene, Humboldt and 5 more	71 min
Dec 15, 5:22 PM CST	Severe Thunderstorm Warning Destructive damage threat	DMX	Carroll, Crawford, Sac	23 min
Dec 15, 5:22 PM CST	Severe Thunderstorm Warning Considerable damage threat	DMX	Adair, Adams, Clarke, Decatur, Madison, Ringgold and 3 more	68 min
Dec 15, 5:36 PM CST	Tornado Warning	DMX	Calhoun, Humboldt, Kossuth, Palo Alto, Pocahontas	24 min
Dec 15, 5:38 PM CST	Tornado Warning Tornado observed	DMX	Boone, Calhoun, Greene, Hamilton, Webster	37 min
Dec 15, 5:45 PM CST	Tornado Warning	DMX	Calhoun, Pocahontas, Webster	30 min
Dec 15, 5:52 PM CST	Severe Thunderstorm Warning Destructive damage threat	DMX	Boone, Franklin, Hamilton, Hancock, Hardin, Humboldt and 6 more	53 min
Dec 15, 5:58 PM CST	Tornado Warning	DMX	Hancock, Humboldt, Kossuth, Palo Alto, Pocahontas	32 min

Nearby

Tornado Warnings in Iowa, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.